题库网 (tiku.one)

 找回密码
 立即注册

 

      

上传图片附件

未使用图片

小贴士: 允许的图片文件格式为: gif, jpg, jpeg, png, webp,上传完成后会在上方生成预览,用鼠标连续双击缩略图,或拖动缩略图,该图片就被绑定至本题,显示在题目下方

本次作答已使用

小贴士: 此栏目显示的是当前作答使用的所有图片,绑定到某一题目的图片同时会显示在该题目下方; 删除使用的图片会将其转移到<未使用图片>类别


习题练习:gc textbook chapter 7 Linear Momentum



 作者: admin   总分: 102分  得分: _____________

答题人: 匿名未登录  开始时间: 24年12月27日 14:40  切换到: 整卷模式

标记此题
1#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
We claim that momentum is conserv6fjjhjikil1(z 6+ l)ded, yet most moving objects eventually slow down and stop. Eij1j6l) l k6h(jzfd+i xplain.
参考答案:    

标记此题
2#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
When a person jumps from a tree to the ground, what happens to the momentum of tw itb0d-6 stq;he person upon striking the g tt-;6b0qw sdiround?
参考答案:    

标记此题
3#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
When you release an infla8cww 3/ *l-du bt:rpfyted but untied balloon, why does it fly across the room? fc38r ptwub*y/- wdl:
参考答案:    

标记此题
4#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
It is said that in ancient times a rich man tzh*o 7n0;adzwith a bag of gold coins froze to death while stdnz0z;t *h7oa randed on a frozen lake. Because the ice was frictionless, he could not push himself to shore. What could he have done to save himself had he not been so miserly?
参考答案:    

标记此题
5#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
How can a rocket change direction when it is far out in space9vr gr4iw31 4h7 zigso and is essentially in a vacuumg3ho9v71srzg iwir 44 ?
参考答案:    

标记此题
6#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
According to Eq. 7–5, the longe o 2y1lb wbay/e.ax, ishi.g9:r the impact time of an impulse, the smaller the force can be for the same momentum change, and hence the smaller the de g2ybi a,w.. yxo /sblea1i9h:formation of the object on which the force acts. On this basis, explain the value of air bags, which are intended to inflate during an automobile collision and reduce the possibility of fracture or death.
参考答案:    

标记此题
7#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Cars used to be built as rigid as po * i)f h,gadh).r0wq1u1vp pcer1- vlassible to withstand collisions. Today, though, cars are designed to have “crumple zones” that collapse upon impact. What is the advantage of thi ec))p1 -hqr f,v raa.1vdw1ul*0gi hps new design?
参考答案:    

标记此题
8#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Why can a batter hit a pitched baseball further t- yq+b hd4+cmyhan a ball tossed in the air by+hy+ 4 bycqd-m the batter?
参考答案:    

标记此题
9#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Is it possible for an object to receive a larger impulse frowl tl kvr-89(ym a small force than8tvw 9-kyllr( from a large force? Explain.
参考答案:    

标记此题
10#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A light object and a heavy object have the same kinq s)tu 28fw5g* or*ugcetic energy. Which has the greater momentum? Explasr5)u8wtuc f*gg o*2 qin.
参考答案:    

标记此题
11#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Describe a collision in7c0c5vipjk/a: f 77j n zkop8k,t4o ot which all kinetic energy is lost.
参考答案:    

标记此题
12#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
At a hydroelectric power plant, water irhxz,jo(1xr7 s directed at high speed against turbine blades on an axle that turns an electric generator. For maximum power generation, should the turbine blades be designed so that the water is brought to a deadzo x,( rj1h7rx stop, or so that the water rebounds?
参考答案:    

标记此题
13#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A squash ball hits a wap hi:9zuoja7 uc3:7fo y: m0aall at a 45 $^{\circ} $ angle as shown in Fig. below. What is the direction (a) of the change in momentum of the ball, (b) of the force on the wall?
参考答案:    

标记此题
14#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A Superball is dropped from a height h onto a hard steel plapdmrgg65 u*gwh)f.jdl6v 5 8tte (fixed to the Earth), from which it rebounds at very nearly its original speed. (a) Is the momentum of the ball conserved during any part of this process? (b) If we consider the ball and Earth as our system, during what parts of the process is momentum conserved? (c) An gt)6 8jwrdfdl5ph 5mg6 .uvg*swer part (b) for a piece of putty that falls and sticks to the steel plate.
参考答案:    

标记此题
15#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Why do you tend to lean backward when carf6- )kmdw r;a0s zcc,crying a heavy load in your arms?
参考答案:    

标记此题
16#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Why is the CM of a 1-m length of pipe atn sbupqlf0856 its mid-point, whereas this is not true for your arm or leg?q un6ps85 bf0l
参考答案:    

标记此题
17#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Show on a diagram ho:wvv2 *bqx20w;ucuj 8 q8yt3)wgv htdw your CM shifts when you change from a lying position to a sitting positq :w ywq02v2cvv*x jd tt)8;bh8u3gwuion.
参考答案:    

标记此题
18#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
If only an external force can change the momentum of the center of mass of mn 9;,(bwhl41jqh 6 f sfsi3glan object, how can the internal force of an engiw hi4q69 ,j ;1sl3fnblhmsgf(ne accelerate a car?
参考答案:    

标记此题
19#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A rocket following a5u4ixaj s p/no hln*(2-mac l: parabolic path through the air suddenly explodes into many pieces. What can you say about the motion of this system x*n aha 2mcjol4l(:psn /-5u iof pieces?
参考答案:    

标记此题
20#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the magnitude of the x3c flajuu8uob :o m-zf3lf1ty/16k4 momentum of a 28-g sparrow flying with a speed of $8.4 \; m/s$    $kg \; m/s$

参考答案:     查看本题详细解析

标记此题
21#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A constant friction force of 25 N acts on a 651:etxmt ox7h 2zwg2/ o-kg skier for 20 s. What is the skto2xx:h2g tm7/o1 w ezier’s change in velocity?    m/s

参考答案:     查看本题详细解析

标记此题
22#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 0.145-kg baseball pitched at 39 m/s is hit on a horizontal line drivet( wlwcw3y:-l straight back toward the pitcher at 52m/s If the contact time betweenw ( -w3llyc:tw bat and ball is $3\times10^{-3}$s calculate the average force between the ball and bat during contact.    N

参考答案:     查看本题详细解析

标记此题
23#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A child in a boat throws a 6.e d k+ h os47.tzz2y1upou-et:40-kg package out horizontally with a speed of 10 m/s Fig. below Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 26.0 kg, and that ofyp:zdko- + toe4euu. 1szh 7t2 the boat is 45.0 kg. Ignore water resistance. The magnitude of the velocity of the boat is    m/s


参考答案:     查看本题详细解析

标记此题
24#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Calculate the force exerted on a rocket, given that the propellinc09 9de4o6yjupjq/z ag gases are expelled at a rate 4poj9y/uezac9q6dj 0of $1500 \; kg/s$ with a speed of $ 4\times10^{4 } \; m/s$ (at the moment of takeoff). F =    $\times 10^7 \; N$

参考答案:     查看本题详细解析

标记此题
25#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 95-kg halfback movinwp5va1f hft8mdzr( 76g at $4.1 \; m/s$ on an apparent breakaway for a touchdown is tackled from behind. When he was tackled by an 85-kg cornerback running at $5.5 \; m/s$ in the same direction, what was their mutual speed immediately after the tackle?    $m/s$

参考答案:     查看本题详细解析

标记此题
26#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 12,600-kg railroad car travels alone on alevel frictionldvcrltq* pxgj*7d: 15g41hf)lly e*less track with a constant speed of 18m/s A 5350-kg load,initially at rest, is dropped onto the car. What will be the car’:dt*)llqp7v e x 54rcjl* h 1yg*ld1gfs new speed?    m/s

参考答案:     查看本题详细解析

标记此题
27#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 9300-kg boxcar traveling e fj ut.c7 dp*aavg5g+u:s2v+ yud/n1at $15 \; m/s$ strikes a second boxcar at rest. The two stick together and move off with a speed of $6 \; m/s$ What is the mass of the second car?    $m/s$

参考答案:     查看本题详细解析

标记此题
28#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  During a Chicago storm, winds can whip horizontally at speed9kjbxoikf9 +xu*x * /ns of 100km/h If the air strikes a person at the rate of 40kg/s per square meter and is brought to rest, estimate the force of the wind on akkx9x* i9 + *fnbjoux/ person. Assume the person is 1.50 m high and 0.50 m wide. Compare to the typical maximum force of friction $\mu\approx1.0$ between the person and the ground, if the person has a mass of 70 kg.    N
$F_{on person}$   $F_{fr}$

参考答案:     查看本题详细解析

标记此题
29#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 3800-kg open railroad car coasts along with a constant s079 qspn) jqzppeed of 8.6m/s on a level track. Snow begins to fall vertically and fills the car at a rate of 3.5kg/min Ignoring frictspq q7jn0)9zp ion with the tracks, what is the speed of the car after 90.0 min?$\approx$    m/s

参考答案:     查看本题详细解析

标记此题
30#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An atomic nucleus initially moving at 420m/s emits an alpha particle 5 asu )t25wy-trt+xigybj (1u in the direction of its velit 52(wa) xy+u yt5jgrs-but1ocity, and the remaining nucleus slows to 350m/s If the alpha particle has a mass of 4.0 u and the original nucleus has a mass of 222 u, what speed does the alpha particle have when it is emitted?    m/s

参考答案:     查看本题详细解析

标记此题
31#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 23-g bullet traveling 230m/s penetrt7mk1y4dtve-zx 9 4vh b7 ve2rates a 2.0-kg block of wood and emerges cleanly at 170m/s If the block e2ty9d4xmv17h-r tvekz 7v4 bis stationary on a frictionless surface when hit, how fast does it move after the bullet emerges?    m/s

参考答案:     查看本题详细解析

标记此题
32#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 975-kg two-stage rocket is traveliz6ub;1j div :ing at a speed of $5.80\times10^3\mathrm{~m/s}$ with respect to Earth when a pre-designed explosion separates the rocket into two sections of equal mass that then move at a speed of $2.20\times10^3\mathrm{~m/s}$ relative to each other along the original line of motion. Let “A” represent the upper stage (that moves away faster) and “B” represent the lower stage.
(a) What are the speed and direction of each section (relative to Earth) after the explosion? $v'_A$   m/s    $v'_B$   m/s  
(b) How much energy was supplied by the explosion? [Hint: What is the change in KE as a result of the explosion? $a\times10^8$ a =    J

参考答案:     查看本题详细解析

标记此题
33#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A rocket of total mass 3180 kg /vpgu.si sc .dvqq42*is traveling in outer space with a velocity of 115m/s To alter its .q.vsvuqpi s4cg2 */d course by 35.0 $^{\circ} $, its rockets can be fired briefly in a direction perpendicular to its original motion. If the rocket gases are expelled at a speed of 1750m/s how much mass must be expelled?    kg

参考答案:     查看本题详细解析

标记此题
34#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A golf ball of mass 0.045 kg is hit off the tee at a speed of 45m/s The gol 62gb 5mz3ya,w9;)j2xj mz sxkso.hv af club was iz2vz2y ;h,)sx9s. 6mak jajmb gxo35 wn contact with the ball for $3.5\times10^{-3}$s Find (a) the impulse imparted to the golf ball,    kg*m/s
(b) the average force exerted on the ball by the golf club.    N

参考答案:     查看本题详细解析

标记此题
35#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 12-kg hammer strikes a nail at a velocity of b0eu)i.pnb*f 9s5e2x3)n h/myvavuh 8.5m/s and comes to rest in a time interval of 8.0 e0ip5uvs.ne9num2)3 h)*/b b ahvf yx ms. (a) What is the impulse given to the nail?    kg*m/s
(b) What is the average force acting on the nail?    N

参考答案:     查看本题详细解析

标记此题
36#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A tennis ball of mass m=0.06k- dok)jz2 e5xbg and speed v=25m/s strikes a wall at a 45 $^{\circ} $ angle and rebounds with the same speed at 45 $^{\circ} $ (Fig. 7–32). What is the impulse (magnitude and direction) given to the ball?   kg*m/s to the  


参考答案:     查看本题详细解析

标记此题
37#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are the design engineer in charge of the crashworthiness (5/ xnctl miq;of new automobile modeln cq (;t5xli/ms. Cars are tested by smashing them into fixed, massive barriers at 50km/h (30 mph). A new model of mass 1500 kg takes 0.15 s from the time of impact until it is brought to rest. (a) Calculate the average force exerted on the car by the barrier. $\approx$$a\times10^5$N a =   
(b) Calculate the average deceleration of the car.    m/$s^2$

参考答案:     查看本题详细解析

标记此题
38#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 95-kg fullback is running at 4m/s to the east and is stopped ydv-f,e xz 6:cin 0.75 s by a head-on tackle by a tackler running due wvc yxf, e6-:zdest. Calculate
(a) the original momentum of the fullback    kg*m/s
(b) the impulse exerted on the fullback    kg*m/s
(c) the impulse exerted on the tackler,    kg*m/s
(d) the average force exerted on the tackler.    N

参考答案:     查看本题详细解析

标记此题
39#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Suppose the force acting on a tennis ball (mass weg.txuk) +r t *.0, rqwcyjn-hcvc8- 0.060 kg) points in the +x direction and is given by the graph of Fig. 7–33 as a func*n 8r hqwkwc-vc,-+ u0.ert j).xtgcy tion of time. Use graphical methods to estimate
(a) the total impulse given the ball    N*s
(b) the velocity of the ball after being struck, assuming the ball is being served so it is nearly at rest initially.    m/s



参考答案:     查看本题详细解析

标记此题
40#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  From what maximum height cab ,dou5hcro; *3go-fan a 75-kg person jump without breaking the lower leg bone of either leg? Ignore air resistance and assume the CM of the person moves a distance of 0.60 m from the standing to the seated position (that is, in breaking the fall). Assume hc3bo f* g;a-rou do,5the breaking strength (force per unit area) of bone is $170\times10^6\mathrm{~N/m^2}$ and its smallest cross-sectional area is $2.5\times10^{-4}m^2$ [Hint: Do not try this experimentally.]    m

参考答案:     查看本题详细解析

标记此题
41#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball of mass 0.440 kg moving epnsr2 kxb-de,gsjs-9(bw -r /ast (+x direction) with a speed of collides head-on with a 0.220-kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?Let A represent the 0.440-kg ball, and B repr(dsws-r sn, g-/ex 9 bpj2-rkbesent the 0.220-kg ball. $v'_A$    m/s    $v'_B$    m/s  

参考答案:     查看本题详细解析

标记此题
42#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 0.450-kg ice puck, moving east with a speed of 3m/s has a head-on collisio( 4zn jxkn9tw(,jc-(jgl j zm)n with a 0.900-kg puck initially at rest. Assuming a perfectly elastic collision, what will be the speed and direction of each object after the collision?Let mk c,((-)jnt( j jlgj49xnwz zA represent the 0.450-kg puck, and let B represent the 0.900-kg puck. v'$_A$ =    m/s   v'$_B$ =    m/s 

参考答案:     查看本题详细解析

标记此题
43#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two billiard balls of equal mass .k: oq,--zextdzeg s ds8:*kcundergo a perfectly elastic head-on collision. If one ball’s initial speed was 2m/s and the other’s was 3m/s in.*8g- :o sdk:kse-d zq x,zcte the opposite direction, what will be their speeds after the collision?(Let A represent the ball moving at 2.00 m/s, and call that direction the positive direction.Let B represent the ball moving at 3.00 m/s in the opposite direction. ) v'$_A$ =    m/s v'$_B$ =    m/s

参考答案:     查看本题详细解析

标记此题
44#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 0.060-kg tennis ball, yprb6lbvf)a 7o 2y8a3moving with a speed of 2.5m/s collides head-on with a 0.090-kg ball initially moving away from it at a speed of 1.15m/s Assuming a perfectly elastic collision, what are the speed and direction of each ball after the7b2b yp36)ay 8lfo var collision?(Let A represent the 0.060-kg tennis ball, and let B represent the 0.090-kg ball.)v'$_A$ =    m/s v'$_B$ =    m/s

参考答案:     查看本题详细解析

标记此题
45#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A softball of mass 0.220 kg that is moving with ):a t5qp oz+iba speed of 8.5m/s collides head-on and elastically with another ball initially at rest. Afterward the incoming softball bounces backward with a speed of 3.7m/s Calculab ):apz5to+i qte
(a) the velocity of the target ball after the collision    m/s
(b) the mass of the target ball.    kg
(Let A represent the moving softball, and let B represent the ball initially at rest.)

参考答案:     查看本题详细解析

标记此题
46#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two bumper cars in an amusement park ride collide el 11ashk(u)ko7p/p dut; ii *ewastically as one approaches the other directly from the rear (Fig. 7–34). Car A has a mass of 450 kg and car B 550 kg, owing to differences in passenger mass. If car A approaches at 4.5m/s and car B is moving atkpkh ua1 ; iodw)7* s/ptui1e( 3.7m/s calculate
(a) their velocities after the collision v'$_A$ =    m/s v'$_B$ =    m/s
(b) the change in momentum of each.$\Delta p_{\mathrm{A}}$$\approx$    kg*m/s $\Delta p_{\mathrm{B}}$$\approx$    kg*m/s


参考答案:     查看本题详细解析

标记此题
47#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 0.280-kg croquet ball makes alx 1( p vb*ch.eftmggf793e5 rn elastic head-on collision with a second ball initially at rest. The second ball moves off with half the original speed of the fib5g9tf(p.mh x3g* r 1v7lcefe rst ball.
(a) What is the mass of the second ball?    kg
(b) What fraction of the original kinetic energy $(\Delta\mathrm{kE/KE})$ gets transferred to the second ball?   

参考答案:     查看本题详细解析

标记此题
48#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a physics lab, a cube slides down a frictionlej5 q-fa/) pvwcss incline as shown in Fig. 7–35, and elastically strikes another cube at the bottom that is only one-half its mass. If the incline is 30 cm high anv5q /)j fcp-wad the table is 90 cm off the floor, where does each cube land? [Hint: Both leave the incline moving horizontally.]$\Delta x_{m}$$\approx$    m $\Delta x_{M}$$\approx$    m


参考答案:     查看本题详细解析

标记此题
49#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
ake the general case o;sxhh,)zb6wv3 l0 r 3lyu9gi xf an object of mass m$_A$ and velocity v$_A$ elastically striking a stationary object of mass head-on. (a) Show that the final velocities v'$_A$ and v'$_B$ are given by$v_{\mathrm{A}}^{\prime}=\left(\frac{m_{\mathrm{A}}-m_{\mathrm{B}}}{m_{\mathrm{A}}+m_{\mathrm{B}}}\right)\nu_{\mathrm{A}},v_{\mathrm{B}}^{\prime}=\left(\frac{2m_{\mathrm{A}}}{m_{\mathrm{A}}+m_{\mathrm{B}}}\right)\nu_{\mathrm{A}}.$(b) What happens in the extreme case when m$_A$ is much smaller than m$_B$ Cite a common example of this. (c) What happens in the extreme case when m$_A$ is much larger than m$_B$ Cite a common example of this. (d) What happens in the case when m$_A$=m$_B$ Cite a common example.
参考答案:    

标记此题
50#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a ballistic pendulum experiment, projectinbzi:qv(1zq6 m7y 5 qile 1 results in a maximum height h of the pendulum equal to 2 vqn6(qzii 7zyq 5bm1:.6 cm. A second projectile causes the the pendulum to swing twice as high, $h_2=5.2\mathrm{cm}$ The second projectile was how many times faster than the first? $v_1$ =    $v_2$ ([color=rgba(0, 0, 0, 0.85)]Round to three decimal places)

参考答案:     查看本题详细解析

标记此题
51#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 28-g rifle bullet traveling 2*5by nyvu*v5z 30m/s buries itself in a 3.6-kg pendulum hanging on a 2.8-m-long string, which makes the pendulum swing upward in an arc. Determine the vertical and horizontal components of the vb**yy z55vun pendulum’s displacement.vertical$\approx$    m horizontal =    m

参考答案:     查看本题详细解析

标记此题
52#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
(a) Derive a formula for the fraction of kinetic ene7 a++hw/g 5np xn)ww6yrel 8zzrgy lost, $(\Delta\mathrm{KE/KE})$ for the ballistic pendulum collision of Example 7–10. (b) Evaluate for m=14g and M=380g
参考答案:    

标记此题
53#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An internal explosion breaks an object, initially at rest, into twoo4j gwa12 vx+v pieces, one o jo+2v1gv w4axf which has 1.5 times the mass of the other. If 7500 J were released in the explosion, how much kinetic energy did each piece acquire? (Let A represent the heavier particle, and B represent the lighter particle. ) KE'$_A$ =    J KE$_B$ =    J

参考答案:     查看本题详细解析

标记此题
54#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 920-kg sports car c2l7y3obq;r pmssih(x)r g1r2 i55 ekwollides into the rear end of a 2300-kg SUV stopped at a red light. The bumpers lock, the brakes are locked, and the two cars skid forward 2.8 m before stopping. The police officer, knowing that the coefficient of kinetic friction between tires and road is 0.80, calculates the speed of the sports car at impact. Whatm(go5)w3b25qri7;se2 rix h 1ypls kr was that speed?(Let A represent the sports car, and B represent the SUV) $\approx$    m/s

参考答案:     查看本题详细解析

标记此题
55#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball is dropped from a height of 1.50 m and rebounds to 9i/fou ws 3i)ka height of 1.20 m. Approximately how many rkwu) o3 /i9ifsebounds will the ball make before losing 90% of its energy?   

参考答案:     查看本题详细解析

标记此题
56#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A measure of inelasticity in a head-on collision of two objects is the nh8mairi .e 16coefficient of restitution, e,ar1in eh68 im. defined as$e=\frac{\nu_\mathrm{A}^{\prime}-\nu_\mathrm{B}^{\prime}}{\nu_\mathrm{B}-\nu_\mathrm{A}},$
where $\nu_\mathrm{A}^{\prime}-\nu_\mathrm{B}^{\prime}$ is the relative velocity of the two objects after the collision and $\nu_\mathrm{B}-\nu_\mathrm{A}$ is their relative velocity before it.
(a) Show that e=1 for a perfectly elastic collision, and e=0 for a completely inelastic collision.
(b) A simple method for measuring the coefficient of restitution for an object colliding with a very hard surface like steel is to drop the object onto a heavy steel plate, as shown in Fig. 7–36. Determine a formula for e in terms of the original height h and the maximum height h’ reached after one collision.

参考答案:    

标记此题
57#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A wooden block is cut into two pieces, one with thrx;uph8ma9y.cc 6q wp5ee times the mass of the other. A depression is made in both faces of the cut, so that a firecracker can be placed in it with the block reassembled. The reassembled block is set on a rough-surfaced table, and the fuse is lit. When the firecracker explodes, the two blocks separate and slide apart. What is the xhc m9up cq;5w.6 pya8ratio of distances each block travels? 

参考答案:     查看本题详细解析

标记此题
58#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 15.0-kg object moving in the +x direction at 5.5m/s col:.spbkfg n xjws +:jb(1jk2y,lides head-on with a 10jj ( +sp:,fg n.yks1xbw:b2 kj.0-kg object moving in the -x direction at 4m/s Find the final velocity of each mass if:
(a) the objects stick together;   m/s
(b) the collision is elastic; v'$_A$ =    m/s v'$_B$ =    m/s
(c) the 15.0-kg object is at rest after the collision;   m/s 
(d) the 10.0-kg object is at rest after the collision;   m/s 
(e) the 15.0-kg object has a velocity of 4m/s in the -x direction after the collision. .   m/s 
Are the results in (c), (d), and (e) “reasonable”? Explain
( Let A represent the 15.0-kg object, and let B represent the 10.0-kg object.)

参考答案:     查看本题详细解析

标记此题
59#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A radioactive nucleus at rest decays intd zy v41:w)2t x.ib lrmosyt+0o a second nucleus, an electron, and a neutrino. The electron and neutrino are emitte4. xwo02td1yt vlb sziy+:m)r d at right angles and have momenta of $9.30\times10^{-23}kg\cdot m/s$ and $5.40\times10^{-23}\mathrm{~kg}\cdot\mathrm{m/s}$ respectively. What are the magnitude and direction of the momentum of the second (recoiling) nucleus?    $ \times10^{-22}$    $^{\circ} $ from the momentum of the electron

参考答案:     查看本题详细解析

标记此题
60#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An eagle ($m_{\mathrm{A}}=4.3\mathrm{kg}$) moving with speed $\nu_\mathrm{A}=7.8\mathrm{~m/s}$ is on a collision course with a second eagle ($m_{\mathrm{B}}=5.6\mathrm{kg}$) moving at $\nu_{\mathrm{B}}=10.2\mathrm{m/s}$ in a direction perpendicular to the first. After they collide, they hold onto one another. In what direction, and with what speed, are they moving after the collision? v =    m/s $\theta$ =    $^{\circ} $ rel. to eagle  

参考答案:     查看本题详细解析

标记此题
61#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Billiard ball A of manxcs f: :ed0 h 724i jj)up+s0rf0aeyyss $m_\mathrm{A}=0.400$kg moving with speed $\nu_\mathrm{A}=1.80$m/s strikes ball B, initially at rest, of mass $m_\mathrm{B}=0.500$kg As a result of the collision, ball A is deflected off at an angle of 30.0 $^{\circ} $ with a speed $\nu_\mathrm{A}^{\prime}=1.10$m/s (a) Taking the x axis to be the original direction of motion of ball A, write down the equations expressing the conservation of momentum for the components in the x and y directions separately. (b) Solve these equations for the speed v'$_B$ and angle $\theta_{\mathrm{B}}$ of ball B. Do not assume the collision is elastic. $\theta_{\mathrm{B}}$ =    $^{\circ} $ v'$_B$ =    m/s

参考答案:     查看本题详细解析

标记此题
62#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  After a completely inelastic collision between two objects of equalq-al7o )rk2zi mass, each having initial arzi7o)2lk- qspeed the two move off together with speed v/3 What was the angle between their initial directions?    $^{\circ} $

参考答案:     查看本题详细解析

标记此题
63#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two billiard balls of equal mass move at right angles and meet at the origin of )4cysq3cs:jfwib6rq 4f 5 at)an xy coordinate system. Ball A is moving upward along the y axis at 2m/s and ball B is moving to the right along the x axis with speed 3.7m/s After the coll 6sfq): c5yas4w 4irq3jc)ft bision, assumed elastic, ball B is moving along the positive y axis (Fig. 7–37). What is the final direction of ball A and what are their two speeds? direction of ball A is   v'$_A$ =    m/s v'$_B$ =    m/s


参考答案:     查看本题详细解析

标记此题
64#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A neon atom (m=20u) makes a perfectly elastic collision withda 96gmeaq*n8 another atom at rest. After the qnag96eam8 d* impact, the neon atom travels away at a 55.6 $^{\circ} $ angle from its original direction and the unknown atom travels away at a -50 $^{\circ} $ angle. What is the mass (in u) of the unknown atom? [Hint: You can use the law of sines.](Let A represent the incoming neon atom, and B represent the target atom) $m_B$   u

参考答案:     查看本题详细解析

标记此题
65#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A neon atom (m=20u) makes a perfectly elastic collimv*5h eir: b(jsion with another atom at rest. After *r mbevj(h5i:the impact, the neon atom travels away at a 55.6 $^{\circ} $ angle from its original direction and the unknown atom travels away at a -50 $^{\circ} $ angle. What is the mass (in u) of the unknown atom? [Hint: You can use the law of sines.](Let A represent the incoming neon atom, and B represent the target atom) $m_B$   u

参考答案:     查看本题详细解析

标记此题
66#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Find the center of mass of the three-mass system s0a uk77;mm *glvjiot .hown in Fig. 7–38. Specify relative to the left-hand 1.00-kg massm.; j *l gmoiau77k0vt.    m


参考答案:     查看本题详细解析

标记此题
67#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The distance between a carbon atomvr6+9p/ qfu2 jhi mnn. ($m_{\mathrm{C}}=12\mathrm{u}$) and an oxygen atom ($m_{\mathrm{O}}=16\mathrm{u}$) in the CO molecule is $1.13\times10^{-10}$m How far from the carbon atom is the center of mass of the molecule?    $\times10^{-11}$m

参考答案:     查看本题详细解析

标记此题
68#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The CM of an empty 1050-kg car is 2.50 m behind the front ofuvob bang97h:6mp z- ts/l(6f the car. How far from the front of the car will the CM be when two people sit in the front seat 2.80 m from the front of the car, and three people sit in the back seat 3.90 m from the front? Assume that each person has a magz7uolh9 f6(: -/mbasn p6tbvss of 70.0 kg.    m

参考答案:     查看本题详细解析

标记此题
69#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A square uniform raft, 18 m by 18 m, of mass 6800gjv xff683+qm kg, is used as a ferryboat. If three cars, each of mass 1200 kg, occupy its NE, SE, and SW corners, determine the CM of the loaded f3+8mj6 fgfvq xerryboat.$X_{CM}$ =    m $Y_{CM}$ =    m

参考答案:     查看本题详细解析

标记此题
70#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three cubes, of sidel ;nf( em,y buje5v-kisd,; o+s $l_0$,$2l_0$, and $3l_0$ are placed next to one another (in contact) with their centers along a straight line and the $l=2l_{0}$ cube in the center (Fig. 7–39). What is the position, along this line, of the CM of this system? Assume the cubes are made of the same uniform material. $X_{CM}$ =    $l_0$ from the    edge of the smallest cube



参考答案:     查看本题详细解析

标记此题
71#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A (lightweight) pallet has a load of identical cases of tomato pay0ny5lu ws-vrq9* ke6ste (see Fig. 7–40), each of which is a cube of length l. Find the center 9yyv q*-ukn60e5s rwlof gravity in the horizontal plane, so that the crane operator can pick up the load without tipping it.$X_{CM}$ =    l $Y_{CM}$ =    l



参考答案:     查看本题详细解析

标记此题
72#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A uniform circular plate of radius 2R has a circular (7p3 bmpmtt56tgf .mehole of radius R cut out of it. The cenf mt .e65mb7p3pg(m ttter of the smaller circle is a distance 0.80R from the center C of the larger circle, Fig. 7–41. What is the position of the center of mass of the plate? [Hint: Try subtraction.]   R


参考答案:     查看本题详细解析

标记此题
73#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Assume that your proportwy2-yfnao s ussx (;-: ;zy)kzions are the same as those in Table 7–1, and calculate the mass of one of your le snaf)-ou yzxzyy( wss;;:-2k gs.    kg


参考答案:     查看本题详细解析

标记此题
74#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Determine the CM of an outstretc,u9 zut0;gegu hed arm using Table 7–1.   % of the person's height along the line from the shoulder to the hand


参考答案:     查看本题详细解析

标记此题
75#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Use Table 7–1 to calculate the position ooa;rk5w h2 ra8f the CM of an arm bent at a right angle. Assume that the pers5aah ;or8 wk2ron is 155 cm tall. $X_{CM}$ =    cm $Y_{CM}$ =    cm


参考答案:     查看本题详细解析

标记此题
76#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
When a high jumper is in a position such that his arms and legs s.da j l-krgwnt/25gol* 8hg( are hanging vertically, and his trunk and head are horizontal, calculate how far below the torso’s median line the CM will be. Will this CM b. n5d 8l(*r/wgkhj otgsg 2-lae outside the body? Use Table 7–1.
参考答案:    

标记此题
77#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
The masses of the Earth aeis:9v- v7(ysx)vj :fq9ednz nd Moon are $5.98\times10^{24}$kg and $7.35\times10^{22}$kg respectively, and their centers are separated by $3.84\times10^{8}$m (a) Where is the CM of this system located? (b) What can you say about the motion of the Earth–Moon system about the Sun, and of the Earth and Moon separately about the Sun?
参考答案:    

标记此题
78#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 55-kg woman and an 80-kg man xt i)j6xh8k7fzkfn-(stand 10.0 m apart on frictionless ice.
(a) How far from the woman is their CM?    m from the woman
(b) If each holds one end of a rope, and the man pulls on the rope so that he moves 2.5 m, how far from the woman will he be now?    m
(c) How far will the man have moved when he collides with the woman? He has moved    m from his original position

参考答案:     查看本题详细解析

标记此题
79#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A mallet consists of a uniform cylindrical head of mass 2.00 kgyji+i:v c5l j.+b. oko and a diameter 0.0800 m mounted on a uniform cylindrical handle of mass 0.500 kg and length 0.240 m, as shown in Fig. 7–42. If this mallet is tossed, spinning, into the air, how far above the bottom of the handle is the point that will follow a parai lj.+.ko:vcbo 5yj+i bolic trajectory?    cm

参考答案:     查看本题详细解析

标记此题
80#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A mallet consists of a unifo f;ly.n2 wrwbvmj:m*q,k p*2c rm cylindrical head of mass 2.00 kg and a diameter 0.0800 m mounted on a uniform cylindrical handle of mass 0.500 kg and length 0.240 m, as shown in Fig. 7–42. If this mallet irfv:j wlc pb*qw m.*,2y;2 nmks tossed, spinning, into the air, how far above the bottom of the handle is the point that will follow a parabolic trajectory?    d    d


参考答案:     查看本题详细解析

标记此题
81#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  (a) Suppose that in Example zqgc ktjbn6mh2 jv1:1/3/mmg 7–14 (Fig. 7–29), $m_{II}$=3$m_{I}$ Where then would $m_{II}$ land?    d(Round to two decimal places)
(b) What if $m_{I}$=3$m_{II}$    d


参考答案:     查看本题详细解析

标记此题
82#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A helium balloon and its gondola, of mass M6rviv+fbe8oi f(z7xp84dt2ge bn31q , are in the air and stationary with respect to the groun28xevo18q74nfg bbve + pt6 f(izr 3idd. A passenger, of mass m, then climbs out and slides down a rope with speed measured with respect to the balloon. With what speed and direction (relative to Earth) does the balloon then move? What happens if the passenger stops?
参考答案:    

标记此题
83#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An 0.145-kg baseball pitched horizontally at strikes a bat and is popped b7e 6js+, jbzgstraight up to a height of 55.6 m. If the contact time is 17e6jb,szg+ bj.4 ms, calculate the average force on the ball during the contact.    $^{\circ} $

参考答案:     查看本题详细解析

标记此题
84#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A rocket of mass m trajp6wn7 ; hw ss2vzrj1)veling with speed $v_0$ along the x axis suddenly shoots out fuel, equal to one-third of its mass, parallel to the y axis (perpendicular to the rocket as seen from the ground) with speed 2$v_0$ Give the components of the final velocity of the rocket.$P_x$: v'$_x$=    $v_0$
$P_y$: v'$_y$=    $v_0$

参考答案:     查看本题详细解析

标记此题
85#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A novice pool player is faced with the corner pocket shotui e .dk4i nlaop-,f(7m*p/fneu+ h6r shown in Fig. 7–43. Relative dimensions are also shown. Should the player be worried about this being a “scratch shot,” in which the4,u 6f.i7pkn*leo- +unapr(e /ihmfd cue ball will also fall into a pocket? Give details.
参考答案:    

标记此题
86#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 140-kg astronaut (including space suit) acquires a speed of 2.5m/s by push*wxupbpd z:f o+9ml d /wm4yws)-ub85 ing off with his legs from an 1800-kg space capsumw8-uyxp4z+wfm u l*9p5/:)wbodds b le.
(a) What is the change in speed of the space capsule?    m/s
(b) If the push lasts 0.40 s, what is the average force exerted on the astronaut by the space capsule? As the reference frame, use the position of the space capsule before the push.    N

参考答案:     查看本题详细解析

标记此题
87#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two astronauts, one of mass 60 kg and the other 80 kg, are initially at res f)4 wis+ z+dcups5dj5t in outer space. They then push each other apart. How far apart are they when the lighter astronaut hasdsw c+5spi jz 5)4f+ud moved 12 m?    m

参考答案:     查看本题详细解析

标记此题
88#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball of mass m makes a head-on elastic collision with a second bnqhgi8c0:b ogj ++ike 6 tc+3vall (at rest) and rebounds in the opposite direction with a kih3 +8b+0cngie+jvo g ct6:qspeed equal to one-fourth its original speed. What is the mass of the second ball? $m_B$ =    $m_A$(Round to two decimal places)

参考答案:     查看本题详细解析

标记此题
89#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You have been hired as an expert witness in a courqn2 57l c uvwxob3wc*r/o71yot case involving an automobile accident. The accident involved car A of mass 1900 kg which crashed into stationary car B of mass 1100 kg. The driver of car A applied his brakes 15 m before he crashed into car B. After the collision, car A slid 18 m while car B slid 30 m. The coefficient of kinetic friction between the locked wheels and the road was measured to be 0.60. Show that the driver of car A was exceeding the 55-mph (90km/h) speed limit before applying the boc7nw3/ *ub qyc15 27rwlv xoorakes.    mi/h

参考答案:     查看本题详细解析

标记此题
90#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A golf ball rolls off the top on k ( ;lq-nqrcsd1mk,b 1,ychr8,8r6bh /rr mmf a flight of concrete steps of total vertical height 4.00 m. The ball hits four times on the way down, each time striking the horizontal part of a different step 1.0 m lower. If all collisions are perfectly elastic, what is the bounce height on the fourth bounce when the ball reaches the bottom of t- 81dms1mnb, ,h6/r (clqhkb qkr,ynrm;rc8 rhe stairs?
参考答案:    

标记此题
91#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A bullet is fired vertically into a 1.40-kg 9u)uclwtem29 -zp1l/ yzu ww, block of wood at rest directly above it. If the bullet has a mass of 29.0 g and a speed of 510m/s how high will the blockzl ,9t1wez-y/wuml)29wuuc p rise after the bullet becomes embedded in it?    m

参考答案:     查看本题详细解析

标记此题
92#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 25-g bullet strikes and e; by3pgayle9. m li8-becomes embedded in a 1.35-kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.25, and the impact mei leg; 9y.pl3yab-8drives the block a distance of 9.5 m before it comes to rest, what was the muzzle speed of the bullet?    m/s

参考答案:     查看本题详细解析

标记此题
93#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two people, one of mass 75 kg and the other of mass 60 kg, sve7xz*ae zm01* lv)vpit in a rowboat of mass 80 kg. With the boat initially at rest, the two people, who have been sitting at opposite ends of the boat 3.2 m apart from each other, now exchange seats. How far and in what dir m*vlv x)zp*a1 ez70veection will the boat move? The boat will move    towards the initial position of the 75 kg person(Round to two decimal places)

参考答案:     查看本题详细解析

标记此题
94#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A meteor whose mass was 2v*k thpcv ,+51( quuyl.a; hzu fl.zjabout $ 1\times10^{ 8}$kg struck the Earth ($m_E$=$6 \times10^{ 24}$kg) with a speed of about 15km/s and came to rest in the Earth.
(a) What was the Earth’s recoil speed?    $ \times10^{-13 }$m/s
(b) What fraction of the meteor’s kinetic energy was transformed to kinetic energy of the Earth?    $ \times10^{ -17}$
(c) By how much did the Earth’s kinetic energy change as a result of this collision?    J

参考答案:     查看本题详细解析

标记此题
95#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An object at rest is suy :qx*3e gfff;oz/.ftddenly broken apart into two fragments by an explosion. One fragment acquires twice the kinetic energy of the other. What is the ratio 3o gqy.x;e *f :ft/ffzof their masses?   

参考答案:     查看本题详细解析

标记此题
96#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The force on a bullet 2fatj).q,(q9w m l5un2b iakk is given by the formula F = 580-( $1.8 \times10^{ 5}$t) over the time interval t=0 to t = $3.0 \times10^{-3 }$s In this formula, t is in seconds and F is in newtons.
(a) Plot a graph of F vs. t for t=0 to t=3.0ms
(b) Estimate, using graphical methods, the impulse given the bullet.    N*s
(c) If the bullet achieves a speed of 220m/s as a result of this impulse, given to it in the barrel of a gun, what must its mass be?    kg

参考答案:     查看本题详细解析

标记此题
97#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two balls, of masses7ncp)-qcy qq 5u* oo6q $m_A$ = 40g and $m_B$ = 60g are suspended as shown in Fig. 7–44. The lighter ball is pulled away to a 60$^{\circ} $ angle with the vertical and released.
(a) What is the velocity of the lighter ball before impact?$\approx$    m/s
(b) What is the velocity of each ball after the elastic collision?v'$_A$ $\approx$    m/s v'$_B$ $\approx$    m/s(Round to two decimal places)
(c) What will be the maximum height of each ball after the elastic collision?    m


参考答案:     查看本题详细解析

标记此题
98#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An atomic nucleus at rest decays radioactively into an alpha particlc2hvt 5r m6kr6e and a smaller nucleus. What will be the speed of this recoiling nucleus if the speed of the alpha parti6rcr56 2mhv ktcle is $ 3.8\times10^{5 }$m/s Assume the recoiling nucleus has a mass 57 times greater than that of the alpha particle.    m/s

参考答案:     查看本题详细解析

标记此题
99#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 0.25-kg skeet (clay target) is firedtxe: y,2 2j ia2alhy+j at an angle of 30 $^{\circ} $ to the horizon with a speed of 25m/s (Fig. 7–45). When it reaches the maximum height, it is hit from below by a 15-g pellet traveling vertically upward at a speed of 200m/s The pellet is embedded in the skeet.
(a) How much higher did the skeet go up?    m
(b) How much extra distance, $\Delta{x}$ does the skeet travel because of the collision? $\approx$   


参考答案:     查看本题详细解析

标记此题
100#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A block of mass m=2.2kg slides downhux5iz5 o+-g d a 30.0 $^{\circ} $ incline which is 3.60 m high. At the bottom, it strikes a block of mass M=7kg which is at rest on a horizontal surface, Fig. 7–46. (Assume a smooth transition at the bottom of the incline.) If the collision is elastic, and friction can be ignored, determine
(a) the speeds of the two blocks after the collision,v'$_A$ =    m/s v'$_B$ =    m/s
(b) how far back up the incline the smaller mass will go. $\approx$   (Round to the nearest integer) (Let A represent mass m, and B represent mass M.)


参考答案:     查看本题详细解析

标记此题
101#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In Problem 79 (Fig. 7–46), what is the upper limit on mass mz/w9*pwzh ocro-f0y,gno 0/ a if it is to rebound from M, slide up the 0z,hpooy cna rg o/zw0/*9 wf-incline, stop, slide down the incline, and collide with M again?    kg (Let A represent mass m, and B represent mass M.)


参考答案:     查看本题详细解析

标记此题
102#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The gravitational slingshot effect. Figure 7–(vlc-3x( m sd 7uxf*o0iv ay-v47 shows the planet Saturn moving in the negative x direction ox-l *(x cisvv-7mvfy0a3 (d uat its orbital speed (with respect to the Sun) of 9.6km/s The mass of Saturn is $5.69 \times10^{ 26}$kg A spacecraft with mass 825 kg approaches Saturn. When far from Saturn, it moves in the direction at 10.4km/s The gravitational attraction of Saturn (a conservative force) acting on the spacecraft causes it to swing around the planet (orbit shown as dashed line) and head off in the opposite direction. Estimate the final speed of the spacecraft after it is far enough away to be considered free of Saturn’s gravitational pull.    km/s


参考答案:     查看本题详细解析

  • :
  • 总分:102分 及格:61.2分 时间:不限时
    未答题: 已答题:0 答错题:
    当前第 题,此次习题练习共有 102 道题
    本系统支持习题练习,作业与考试三大模式,作业考试自动评分,成绩排序一键导出,可设定动态变量同一试卷千人千题
    如果您对本系统感兴趣,想加入我们或者想进行任何形式的合作,请加微信 skysky1258

    浏览记录|使用帮助|手机版|切到手机版|题库网 (https://tiku.one)

    GMT+8, 2025-1-30 05:33 , Processed in 0.371445 second(s), 225 queries , Redis On.