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:Physics Unit2: Kinematics One Dimensional Motion



 作者: admin   总分: 149分  得分: _____________

答题人: 匿名未登录  开始时间: 22年07月19日 23:10  切换到: 整卷模式

标记此题
1#
 
单选题 ( 1.0 分) (组内1/93) 切至整卷模式 搜藏此题  
第 1 题组 (共 93 题 103 分)
  Suppose that an object trave yhk p,j/;gszh5rtn- -ls from one point in space to another. Make a comparison between the displacement and ths,jn thr5 ;g/z--hykp e distance traveled.

参考答案:    

标记此题
2#
 
单选题 ( 1.0 分) (组内2/93) 切至整卷模式 搜藏此题  
  When is the average velocity of an object equal to the instantaneous v l9(jci- e0tcnelocity?

参考答案:    

标记此题
3#
 
单选题 ( 1.0 分) (组内3/93) 切至整卷模式 搜藏此题  
  A new car manufacturer advertises that their car can go "from zero to steh-n ocn9(*q ixty in 8 s". This is a descriohe- n9q*ct(n ption of

参考答案:    

标记此题
4#
 
单选题 ( 1.0 分) (组内4/93) 切至整卷模式 搜藏此题  
  An object moving in the +x axixz 27put i 5eynxv.l. 9vs0n*fs experiences an acceleration of $2.0 \; m/s^2$. This means the object is

参考答案:    

标记此题
5#
 
单选题 ( 1.0 分) (组内5/93) 切至整卷模式 搜藏此题  
  Suppose that a car traveling to the East (+x direction) begins to slowl 3;g hqc:+rtc down as it approaches a traffic light. Make a 3;lgc qtr c:h+statement concerning its acceleration.

参考答案:    

标记此题
6#
 
单选题 ( 1.0 分) (组内6/93) 切至整卷模式 搜藏此题  
  Suppose that a car traveling toky)mxg5 p) 9 g,mcnpm3 the West (-x direction) begins to slow down as it approaches a traffic ligg9k xn,mm pmy3 5pc))ght. Make a statement concerning its acceleration.

参考答案:    

标记此题
7#
 
单选题 ( 1.0 分) (组内7/93) 切至整卷模式 搜藏此题  
  Suppose that an object is moving with a constant velocity. Make a statement cq7ovckr;z ,d /v hz;vpr :2bl,m;7 jpponcerning its acceleratvzlbkrv,,;7/;rpz:c q poj7 vm ;p 2hdion.

参考答案:    

标记此题
8#
 
单选题 ( 1.0 分) (组内8/93) 切至整卷模式 搜藏此题  
  If the velocity of an object is zero, k /jguhi:b- q8b :1ymcdoes it mean that the acceleration is zero? Sub::k qjmiy gu/h8b1c-pport your answer with an example.

参考答案:    

标记此题
9#
 
单选题 ( 1.0 分) (组内9/93) 切至整卷模式 搜藏此题  
  Can an object's velocity change direction when its acceleration is constant.xne)(zflt8c oorvz*; f 5i9 h? Suppoilc8 (;5efzf9 o n)r.zt xo*vhrt your answer with an example.

参考答案:    

标记此题
10#
 
单选题 ( 1.0 分) (组内10/93) 切至整卷模式 搜藏此题  
  Suppose that an objectqfw-n+hi2o7 xg0w n)wj3 uju ; is moving with constant acceleration. Make a statement concerning its motion with resjw;qwoi 723+uhn) xf nw0 u-gjpect to time.

参考答案:    

标记此题
11#
 
单选题 ( 1.0 分) (组内11/93) 切至整卷模式 搜藏此题  
  Can an object have increasing speed while its accele) czb -n;1vwg+-dd elcrf04glration is decreasing? Support your answer with angg)zdwc41+el d nvf0l cr;--b example.

参考答案:    

标记此题
12#
 
单选题 ( 1.0 分) (组内12/93) 切至整卷模式 搜藏此题  
  Suppose a can, after an initial kick, moves u n196kt9bmn9,g+ y y4 hqwydlrp along a smooth hill of ice. Make a statement concerning its accelerati n4hyty 6,yl99+nd 9bqrwk1gmon.

参考答案:    

标记此题
13#
 
单选题 ( 1.0 分) (组内13/93) 切至整卷模式 搜藏此题  
  Under what condition is average velohb3u.(mh *ph;0shwvrcity equal to the average of the object's initial and final velocity*; .wu(hh0m3svrh bph?

参考答案:    

标记此题
14#
 
单选题 ( 1.0 分) (组内14/93) 切至整卷模式 搜藏此题  
  Objects A and B both start at rest. They both accelerate at we90hr0lyjl-p+ f f0 9gea- jqthe same rate. However, ehy0l j g9pwj9r0qe-ff-+l0aobject A accelerates for twice the time as object B. What is the final speed of object A compared to that of object B?

参考答案:    

标记此题
15#
 
单选题 ( 1.0 分) (组内15/93) 切至整卷模式 搜藏此题  
  Objects A and B both start from rest. They both accelerate at the samewwy fi4h 7nww;0c*r:q rate. However, object A accelerates for twice the time as obw4cwy hw:w7 irqf0 *;nject B. What is the distance traveled by object A compared to that of object B?

参考答案:    

标记此题
16#
 
单选题 ( 1.0 分) (组内16/93) 切至整卷模式 搜藏此题  
  When an object is releasoxw*x6 ob/cbqk j /y.-ed from rest and falls in the absence of friction, which of the followin*/.w/jq- oxk6bbc oyx g is true concerning its motion?

参考答案:    

标记此题
17#
 
单选题 ( 1.0 分) (组内17/93) 切至整卷模式 搜藏此题  
  When an object is released from rest and falls in the abseeg0m j7 4b3smknce of friction, which of the following is true b43 e0m k7smgjconcerning its motion?

参考答案:    

标记此题
18#
 
单选题 ( 1.0 分) (组内18/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown straight up. Make a statement about the velocity anb2crzws fc:o;-9o3b fd rwbb2 z3co 9-fs;o:cfthe acceleration when the ball reaches the highest point.

参考答案:    

标记此题
19#
 
单选题 ( 1.0 分) (组内19/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown straight up. What is its acceleration jq6tkm n tb14msale7b.;wq 6/r m-7gbsust before it reaches its highest poins47w. m/q e-r 1mgmbstlq;7at k b66bnt?

参考答案:    

标记此题
20#
 
单选题 ( 1.0 分) (组内20/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown straighto, edx-/ cdv1j up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity aevjd/o d-,x c1nd acceleration as the ball is going up.

参考答案:    

标记此题
21#
 
单选题 ( 1.0 分) (组内21/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up, reaches a maximum heig0pby, zfxjo;rivujh+ 7 7 o-bc4 +yq/dt6nwq-ht, then falls to its initial height. Make a statement about the direction of the velocity and accelerzy+jtob6 +vuq4p0xc,7 fdjw o;h -/nq-7ir byation as the ball is coming down.

参考答案:    

标记此题
22#
 
单选题 ( 1.0 分) (组内22/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown n)wk/j jp7.gyjq41 a/ -ac z+ipb3lwx 4,baevdownward in the absence of air resistance. Make a statement concerning its p,j.qn4bja b-g)7 +xvi3 a/kz 14pawcw/ljyeacceleration.

参考答案:    

标记此题
23#
 
单选题 ( 1.0 分) (组内23/93) 切至整卷模式 搜藏此题  
  Suppose a skydiver jumps from a high-flying plane. xu7* 6:bmv9l iir3pc jWhat is her acceleration when she sicr:93 upvj*lbm 7xi6 he reaches terminal velocity?

参考答案:    

标记此题
24#
 
单选题 ( 1.0 分) (组内24/93) 切至整卷模式 搜藏此题  
  A ball is thrown vertically upward with a speedrp) 6n.mqfrx.) )dn6v whs0pt v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the secopmvtx 0.n sn)p)q fr6 whr)6d.nd ball go than the first ball?)

参考答案:    

标记此题
25#
 
单选题 ( 1.0 分) (组内25/93) 切至整卷模式 搜藏此题  
  Ball A is dropped from the top of a building. One second later, ball B i. o ;twnzd)e8.xog3m0 yx+srx s dropped from the same building. As time 0m.. n)o+yzw x;8o gxdtsx3erprogresses, the distance between them

参考答案:    

标记此题
26#
 
单选题 ( 1.0 分) (组内26/93) 切至整卷模式 搜藏此题  
  Ball A is dropped from the top of7a 0ek2873gl tmom yc b9fban/ a building. One second later, ball B is dropped from the samen7yb 27 8 eg0f9mm oblk3aatc/ building. As time progresses, the difference in their speeds

参考答案:    

标记此题
27#
 
单选题 ( 1.0 分) (组内27/93) 切至整卷模式 搜藏此题  
  Two objects are thrown from the top of a tall a8forq v8n 2 atvj 9n-h0tu8(rbuilding. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the streeav8v 289r8r nfqt ujtnha-0o (t?

参考答案:    

标记此题
28#
 
单选题 ( 1.0 分) (组内28/93) 切至整卷模式 搜藏此题  
  A brick is dropped from the top of a buildi ) oyg*eh0-p-sds ir.wng. A second brick is thrown straight down from the same building. They are released at de p w0 -osr*hs.yg)i-the same time. Neglect air resistance. Compare the accelerations of the two bricks.

参考答案:    

标记此题
29#
 
单选题 ( 1.0 分) (组内29/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-zero velocity in the +x az++mf0xd 1sitc7h5 r :p tw2bx:;dtakxis. The position versus time graph of this objecthspt:1db0 f mtt:car++xkdz 7;i52xw is

参考答案:    

标记此题
30#
 
单选题 ( 1.0 分) (组内30/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-zero acceleration in the +x ax :n phnieuh ./-t1i+hhis. The position versush1.hu+ p i-/hn: enhit time graph of this object is

参考答案:    

标记此题
31#
 
单选题 ( 1.0 分) (组内31/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-liv59f, ,tir 4ir3ocg zero velocity in the +x axis. The velocity versus time graph of this t,r, lo 59cf4r igi3ivobject is

参考答案:    

标记此题
32#
 
单选题 ( 1.0 分) (组内32/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-zero acceleration in thbkj4+19kg 3q(5 u7vlmllfh hp e +x axis. The velocity versus time grapvk(u4571 p q llh+9mfkb3jg hlh of this object is

参考答案:    

标记此题
33#
 
单选题 ( 1.0 分) (组内33/93) 切至整卷模式 搜藏此题  
  The slope of a position versus time dvl+sg5o-li)mcu(1kgraph gives

参考答案:    

标记此题
34#
 
单选题 ( 1.0 分) (组内34/93) 切至整卷模式 搜藏此题  
  The slope of a velocity versus time gr2a-z;;xu/ gltz8xp3 s8:bw-yx; d(t xqkxjmqaph gives

参考答案:    

标记此题
35#
 
单选题 ( 1.0 分) (组内35/93) 切至整卷模式 搜藏此题  
  The area under a curve in an acceleratiov 8t xawp538zdrf 1k2bn versus time graph gives

参考答案:    

标记此题
36#
 
单选题 ( 1.0 分) (组内36/93) 切至整卷模式 搜藏此题  
  The area under a curve in a velocity versus t oqo9tzg6;d4s ime graph gives

参考答案:    

标记此题
37#
 
单选题 ( 1.0 分) (组内37/93) 切至整卷模式 搜藏此题  
  If the position versus time grapdk qepb ,s)3 bj-kv)2kh of an object is a horizontal line, the object iseqkbvpjk d,s3 )-)k2b

参考答案:    

标记此题
38#
 
单选题 ( 1.0 分) (组内38/93) 切至整卷模式 搜藏此题  
  If the position versus time graph of an object is a uxqi(3s sh ()xy6px*dvertical line, the object is(s6)x* i 3qy(hdx supx

参考答案:    

标记此题
39#
 
单选题 ( 1.0 分) (组内39/93) 切至整卷模式 搜藏此题  
  If the velocity versus time graph of an object is a horizontal line, the object zkp f29eu)m85e aipo2isfpm2koa5e9pzeu28 i )

参考答案:    

标记此题
40#
 
单选题 ( 1.0 分) (组内40/93) 切至整卷模式 搜藏此题  
  If the velocity versus time graph ofu ;02y dk,/p* u0fizjvmw8ghu an object is a straight line making an angle of 3f2ihjk um zwy08 u g0;uv,d*p/0 degrees with the time axis, the object is

参考答案:    

标记此题
41#
 
单选题 ( 1.0 分) (组内41/93) 切至整卷模式 搜藏此题  
  An object moves 15.0 m north and then 11.0 m south. Find bi4fuda7; 6whz ltct33 oth the distance traveled and the magnitud 736dzl4 tt acuhw3;fie of the displacement vector.

参考答案:    

标记此题
42#
 
单选题 ( 1.0 分) (组内42/93) 切至整卷模式 搜藏此题  
  A boat can move at 30 km/h in still water. How long will it take to move o tacv l.;.gx;12 km upstream in a ;ao t..;vlxgc river flowing 6.0 km/h?

参考答案:    

标记此题
43#
 
单选题 ( 1.0 分) (组内43/93) 切至整卷模式 搜藏此题  
  55 mi/h is how many m/s? (1y7oh+(cemrih7 e 5l-o mi = 1609 m)

参考答案:    

标记此题
44#
 
单选题 ( 1.0 分) (组内44/93) 切至整卷模式 搜藏此题  
  What must be your average speed in order to79 t2kbd y61 fsjzoldad *y(n 70o.ugg travel 350 km in 5.15 h?

参考答案:    

标记此题
45#
 
单选题 ( 1.0 分) (组内45/93) 切至整卷模式 搜藏此题  
  A runner ran the marathon (approximately 42.0 km) in 2 hours an8ej)lsqlk/)vt +it w+d 57 min. What is the average qj+t vl/k)8i s+le) twspeed of the runner in m/s?

参考答案:    

标记此题
46#
 
单选题 ( 1.0 分) (组内46/93) 切至整卷模式 搜藏此题  
  A car travels 90 km/h. How long does it take for it to travel 400 k(ol+rpu-r,k0b mh -*ck5 nqhqm?

参考答案:    

标记此题
47#
 
单选题 ( 1.0 分) (组内47/93) 切至整卷模式 搜藏此题  
  A ly (light year) is the distance that light travels in one year. lku ba92;mzy :The speed of ligy 2a; 9z:umkblht is $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

参考答案:    

标记此题
48#
 
单选题 ( 1.0 分) (组内48/93) 切至整卷模式 搜藏此题  
  If you are driving 72 km/h along a straight road andfrd8,euu1;rd:+g c hp you look to the side for 4.0e,;cf r8gd+uu :d1rh p s, how far do you travel during this inattentive period?

参考答案:    

标记此题
49#
 
单选题 ( 1.0 分) (组内49/93) 切至整卷模式 搜藏此题  
  If you run a complete l t2 zxhxze1 7i)ewdp21oop around an outdoor track (400 m), in 100 s, your average velo1 2ep)dth2xi1xe7zz wcity is

参考答案:    

标记此题
50#
 
单选题 ( 1.0 分) (组内50/93) 切至整卷模式 搜藏此题  
  A polar bear starts at the North Pole. It travels 1.0 km south, g/4)ai kc 6fkuebrf5m w 7l/(pthen 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. Thp/f(u4bi 5c)e a6 gk7k/mfl wris trip takes 45 min. What was the bear's average speed?

参考答案:    

标记此题
51#
 
单选题 ( 1.0 分) (组内51/93) 切至整卷模式 搜藏此题  
  A polar bear starts at the North Pole. It travels 1.0 km south, theb /yn .,nwm1xjpy 12wqn 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point1n ybm, w/2pyn wjxq.1. This trip takes 45 min. What was the bear's average velocity?

参考答案:    

标记此题
52#
 
单选题 ( 1.0 分) (组内52/93) 切至整卷模式 搜藏此题  
  You are driving home on a weekend from school at /cx- ; 5pspm.h+wntrf55 mi/h for 110 miles. It then starts to t /sw5c frm;.p-pn+x hsnow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

参考答案:    

标记此题
53#
 
单选题 ( 1.0 分) (组内53/93) 切至整卷模式 搜藏此题  
  A motorist travels 160 km at 80 km/h and 160 km at m pss9foa4.chzp.8 jaq s*w39100 km/h. What is the averag8*mc .4wzsp fh9s3j aaop9sq. e speed of the motorist for this trip?

参考答案:    

标记此题
54#
 
单选题 ( 1.0 分) (组内54/93) 切至整卷模式 搜藏此题  
  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What*pcq8sic - o 65e x e*iv2.e(kc7fmuqt is her averagetcic-ixpe(c.7 *uvq mk5q8e f6es2o * speed for the trip?

参考答案:    

标记此题
55#
 
单选题 ( 1.0 分) (组内55/93) 切至整卷模式 搜藏此题  
  An airplane travels at 300 mi/h so ygygrfa5uz) , o.p31/bkc :wfuth for 2.00 h and then at 250 mi/h north for 750 miles. /, kbfrpc.5f31z)yy owug :agWhat is the average speed for the trip?

参考答案:    

标记此题
56#
 
单选题 ( 1.0 分) (组内56/93) 切至整卷模式 搜藏此题  
  In a 400-m relay race the anchorman (the person who runs the last 100 m) fod)tl t-l3qvbcm dp,55 r team A can run 100 m in 9t mqp5lt5 ldb-,vc3 )d.8 s. His rival, the anchorman for team B, can cover 100 m in 10.1 s. What is the largest lead the team B runner can have when the team A runner starts the final leg of the race, in order that the team A runner not lose the race?

参考答案:    

标记此题
57#
 
单选题 ( 1.0 分) (组内57/93) 切至整卷模式 搜藏此题  
  A car decelerates uniformly and comes to a stop after 13 s.63lgx ybluj*f/*9 ssb The car's average velocity during deceleration w 6* *xsub3slf/jbly9gas 48 km/h. What was the car's deceleration while slowing down?

参考答案:    

标记此题
58#
 
单选题 ( 1.0 分) (组内58/93) 切至整卷模式 搜藏此题  
  An airplane increases its speed from 100 m/s to 160 m/s, at the average ra**.qkkl* oa mate of *kka.qml**oa $15 \; m/s^2$. How much time does it take for the complete increase in speed?

参考答案:    

标记此题
59#
 
单选题 ( 1.0 分) (组内59/93) 切至整卷模式 搜藏此题  
  A car traveling 60 km/h acvd/+ ,cua8kfu celerates at the rate of $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

参考答案:    

标记此题
60#
 
单选题 ( 1.0 分) (组内60/93) 切至整卷模式 搜藏此题  
  A cart starts from rest and acce,ie q(qnqa -0olerates at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?

参考答案:    

标记此题
61#
 
单选题 ( 1.0 分) (组内61/93) 切至整卷模式 搜藏此题  
  A car travels at 15 m/s for 10 s. It then speeds up with yals/-xb -9 f)lu :pmwkl:xm:a constant acceleration ofm 9l:xu:pm lfk/bl-xw) y-:as $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

参考答案:    

标记此题
62#
 
单选题 ( 1.0 分) (组内62/93) 切至整卷模式 搜藏此题  
  A cart with an initial velocity of 1.4 m/s experiences a constant acceleratz h43 s0v1bvt -ltbhp,ion ofv-4tph3lv bshbtz ,01 $3.5 \; m/s^2$. What is the cart's displacement during the first 5.9 s of its motion?

参考答案:    

标记此题
63#
 
单选题 ( 1.0 分) (组内63/93) 切至整卷模式 搜藏此题  
  A bullet moving horizontally to the right (+xah :2v-- lijlc direction) with a speed of 463 m/s strikes a sandbag and penetrates a distance of 1:ca2- l-lvij h9.03 cm. What is the average acceleration, in $m/s^2$, of the bullet?

参考答案:    

标记此题
64#
 
单选题 ( 1.0 分) (组内64/93) 切至整卷模式 搜藏此题  
  A jet fighter plane is launched from a catapult on an ai rjyi171ryb8zy 2*e: ne y hbe9fy4b8ircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.e1zy4 fry b1ynyh88eb jb9*: 7yr2i ei0 s. Assuming the acceleration is constant, what is the length of the catapult?

参考答案:    

标记此题
65#
 
单选题 ( 1.0 分) (组内65/93) 切至整卷模式 搜藏此题  
  A car starting from rest moves with constant acceleration pa /qwt:-(sbf of $2.0 \; m/s^2$ for 10 s, then travels with constant speed for another 10 s, and then finally slows to a stop with constant acceleration of
-$2.0 \; m/s^2$. How far does it travel?

参考答案:    

标记此题
66#
 
单选题 ( 1.0 分) (组内66/93) 切至整卷模式 搜藏此题  
  A car goes from 40 m/s to 80 m/s in a distance of 200 m. Whatxc20*qc7/d9;a;zuh vnk 3b:u d esdwa is its average accelerhdvn;0a2u:as7 kc*d/ wd 3qbe zc;ux9ation?

参考答案:    

标记此题
67#
 
单选题 ( 1.0 分) (组内67/93) 切至整卷模式 搜藏此题  
  An object starts from rxb* ,e-c*pe mdt/b1a9vm1z kuest and undergoes uniform acceleration. During the first second it travels 5.9pa/km1e1t ,* ueb9mxvd- bzc * m. How far will it travel during the third second?

参考答案:    

标记此题
68#
 
单选题 ( 1.0 分) (组内68/93) 切至整卷模式 搜藏此题  
  An object is moving in a straight line with constant acceleratjm9(rn3 sx5s zc1 vzw)1j7eqx ion. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m1vqszmx 3jn(97rw1 se xc)5zj /s. How far does it move during this time?

参考答案:    

标记此题
69#
 
单选题 ( 1.0 分) (组内69/93) 切至整卷模式 搜藏此题  
  A car starts from rest and accelerates uniforvnf/ah uh,,a6m 9h c.fmly at $3.0 \; m/s^2$. A second car starts from rest 6.0 s later at the same point and accelerates uniformly at $5.0 \; m/s^2$. How long does it take the second car to overtake the first car?

参考答案:    

标记此题
70#
 
填空题 ( 2.0 分) (组内70/93) 切至整卷模式 搜藏此题  
  A car with good tires on a dry road can decelerate at a(y al 0i(n20); e 8m kgu4tr-bjlxncoqbout $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

参考答案:    

标记此题
71#
 
填空题 ( 3.0 分) (组内71/93) 切至整卷模式 搜藏此题  
  At the instant a traffic light turns green, a car that has been wd3w /p* ebcya6aiting at the intersection starts ahead be*wc/a3 d6ypwith a constant acceleration of $2.00 \; m/s^2$. At that moment a truck traveling with a constant velocity of 15.0 m/s overtakes and passes the car.
(a.) Calculate the time necessary for the car to reach the truck.    $s$ (only fill in numerical values)
(b.) Calculate the distance beyond the traffic light that the car will pass the truck.    $m$ (only fill in numerical values)
(c.) Determine the speed of the car when it passes the truck.    $m/s$ (only fill in numerical values)

参考答案:    

标记此题
72#
 
单选题 ( 1.0 分) (组内72/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of. b3we ) jo2eth11bgvl 12 m/s on the surface of planet X where lb1v o)e 1h2bg. ew3jtthe acceleration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

参考答案:    

标记此题
73#
 
单选题 ( 1.0 分) (组内73/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 12 m/s on*kgcvn8)pf)wd*4 q jm:m0i*p6 ec -pa ds+hwg the surface of planet X where the acceleration due to grqc0peg*s6hwk4 )cdd -* j8mm:f ) pp+*inwgavavity is $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

参考答案:    

标记此题
74#
 
单选题 ( 1.0 分) (组内74/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 15 m/s on the surface of pltw+*y(/xkr8v e;*8 jdz zerdqanet X where the (wee +x d d*/q*k8z8tzrryvj;acceleration due to gravity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

参考答案:    

标记此题
75#
 
单选题 ( 1.0 分) (组内75/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 14 m/s gw1jrps* x3m:on the surface of planet X where the acceleration due sm1w3 :rxpg*jto gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

参考答案:    

标记此题
76#
 
单选题 ( 1.0 分) (组内76/93) 切至整卷模式 搜藏此题  
  Human reaction time is usually greater than 0.10 s. If your fk0891b s7ifmu5 uxyw *ppu:ozriend holds a ruler between your fingers and releases it without warning, how far 1bywo79p*kp0 zuu8: u mi5x sfcan you expect the ruler to fall before you catch it?

参考答案:    

标记此题
77#
 
单选题 ( 1.0 分) (组内77/93) 切至整卷模式 搜藏此题  
  A ball is thrown upwardslx ,kdcj) h*9zwe6 9d at a velocity of 19.6 m/s. What is its velocity after 3 z*9k x9sdle)cwhj d6,.00 s?

参考答案:    

标记此题
78#
 
单选题 ( 1.0 分) (组内78/93) 切至整卷模式 搜藏此题  
  A bullet shot straight up returns to its starting point inlh5y4prnh u ca0r;)j/8p5a ez 8i+m aa 8 s. What is the initial speed of the bulleijc;rn hl0 m 588eau5/)a ayazh p+4prt?

参考答案:    

标记此题
79#
 
单选题 ( 1.0 分) (组内79/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up with a speed of 36.0 m/s. Hl)/tdq * 6hd(/vgbjuiow long does it take to return to i/d* ugd 6i /tjh(vbql)ts starting point?

参考答案:    

标记此题
80#
 
单选题 ( 1.0 分) (组内80/93) 切至整卷模式 搜藏此题  
  A ball is thrown downward from thn8mf.d :-iwrl4db9 y re top of a building with an initial speed of 13 m/s. It strikinl.f b8 9:mwrry-d 4des the ground after 4.9 s. How high is the building?

参考答案:    

标记此题
81#
 
填空题 ( 3.0 分) (组内81/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up wi5kh; i ooe )xlu xow3:)g9k5r xm0-nleth a speed of 30 m/s. (only fill in numerical value in txl0o;r)9)i3oun xe mk-e5k: loh wxg5he blanks)
(a.) How long does it take the ball to reach the maximum height?    $s$
(b.) What is the maximum height reached by the ball?    $m$
(c.) What is its speed after 4.2 s?    $m/s$

参考答案:    

标记此题
82#
 
填空题 ( 6.0 分) (组内82/93) 切至整卷模式 搜藏此题  
  A foul ball is hit straight up into the air l.nd ztcuezv. wj2am z,a64 )5dtp99d with a speed of 44.8 m/s. (use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 2 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 8 m above the point of contact between the bat and ball for the first time.  (数值)  $s$
(f.) Determine the time at which the ball pass a point 8.0 m above the point of contact a second time.  (数值)  $s$

参考答案:    

标记此题
83#
 
单选题 ( 1.0 分) (组内83/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the velocit,uq3,okmy69:yjmz n ny at t = 1.0 s?


参考答案:    

标记此题
84#
 
单选题 ( 1.0 分) (组内84/93) 切至整卷模式 搜藏此题  
  In Fig. below, what ixp-xn/ c-b cqjf3 bu):s the velocity at t = 2.5 s?


参考答案:    

标记此题
85#
 
单选题 ( 1.0 分) (组内85/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the velocity at t = 49u9x-iu *mnuov *v7 qeg.ifw4.0 s?


参考答案:    

标记此题
86#
 
单选题 ( 1.0 分) (组内86/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the velocity: p)r2ya 9b78w aprrrg at t = 5.5 s?


参考答案:    

标记此题
87#
 
单选题 ( 1.0 分) (组内87/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average velocity from 0 to 4.0 r:vg0y*q*r * aio u.efeklo8 )s?


参考答案:    

标记此题
88#
 
单选题 ( 1.0 分) (组内88/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average velocity from 0 to ee0 ;ec *: jzlqvui2n h2lr.9f6.0 s?


参考答案:    

标记此题
89#
 
单选题 ( 1.0 分) (组内89/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the acceleratiogt 3-- ycnxko9 8-vgkgn at 1.0 s?


参考答案:    

标记此题
90#
 
单选题 ( 1.0 分) (组内90/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the accelerat 45ljl d9o52pfwdb 8ak*j(n roion at 3.0 s?


参考答案:    

标记此题
91#
 
单选题 ( 1.0 分) (组内91/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average acceleration from 0 to 5.0 sv nay,vm35x;7 o8o7rrk og-ld?


参考答案:    

标记此题
92#
 
单选题 ( 1.0 分) (组内92/93) 切至整卷模式 搜藏此题  
  In Fig. below, what i-kw: 2 xoipqu*ru,n5g s the average acceleration from 0 to 8.0 s?


参考答案:    

标记此题
93#
 
单选题 ( 1.0 分) (组内93/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the displacement from 0 to 8.0 scb.5i 68we;dx /lkiqc?


参考答案:    

标记此题
94#
 
问答题 ( 1.0 分) (组内1/46) 切至整卷模式 搜藏此题  
第 2 题组 (共 46 题 46 分)
Does a car speedometer meas hred8ift1e)x45 tz .aure speed, velocity? {speed|velocity}
参考答案:    

标记此题
95#
 
判断题 ( 1.0 分) (组内2/46) 切至整卷模式 搜藏此题  
  An object can have a varying s; q uz67(p96f7cqdm xmm.phru peed if its velocity is constant.

参考答案:    

标记此题
96#
 
判断题 ( 1.0 分) (组内3/46) 切至整卷模式 搜藏此题  
  The velocity of an object can be negative wh17re+ts;:gtyh) b8g h w,spfpen its acceleration is positive.

参考答案:    

标记此题
97#
 
判断题 ( 1.0 分) (组内4/46) 切至整卷模式 搜藏此题  
  If one object has a greater speed than a seczhz7z4le60lr- xock9 ond object, the first must have a greatezl-r0 7xhzl9czek 6o 4r acceleration.

参考答案:    

标记此题
98#
 
判断题 ( 1.0 分) (组内5/46) 切至整卷模式 搜藏此题  
  Two cars emerge side by q - k4wjbp/ )seu8 rg-xy;.fvzside from a tunnel. Car A is traveling with a speed of $60 \; km/h$ and has an acceleration of $40 \; km/h/min$ Car B has a speed of $40 \; km/h$ and has an acceleration of $60 \; km/h/min$ . Can A will pass car B at the instant they come out of the tunnel.

参考答案:    

标记此题
99#
 
判断题 ( 1.0 分) (组内6/46) 切至整卷模式 搜藏此题  
  An object can be increasing im+kig ) rkpbqx(.8ugngf2 8 k ,rnx51cn speed as its acceleration decreases.

参考答案:    

标记此题
100#
 
填空题 ( 1.0 分) (组内7/46) 切至整卷模式 搜藏此题  
  A baseball player hits a foul ball straight up int ;rhoytl;1 3ia+q8j.f/o vsde rb1p*ws(l1 k ko the air. It leaves the bat with a speed of ei 1/r+lj v hfw(kl;1;d8.rkab*pots13yosq$120 \; km/h$. In the absence of air resistance, how fast will the ball be traveling when the catcher catches it?    $km/h$ (please only fill in numerical value in the blank)

参考答案:    

标记此题
101#
 
单选题 ( 1.0 分) (组内8/46) 切至整卷模式 搜藏此题  
  As a freely falling object spe8q8 m9bdoa :e lcn xcw4y8,w8weds up, what is happening to its acceleration, how does it change if ncdl4wm8bcxwa, woe:8y889q air friction is ignored?

参考答案:    

标记此题
102#
 
单选题 ( 1.0 分) (组内9/46) 切至整卷模式 搜藏此题  
  As a freely falling object speeds up, what is happening to its acceleration,lb x 4nth) 50,yvcguc- how does it changelxu ,g 50tncc)v-hb 4y if air friction CAN NOT be ignored?

参考答案:    

标记此题
103#
 
单选题 ( 1.0 分) (组内10/46) 切至整卷模式 搜藏此题  
  An object that is thrown vertically upward will return to its originalq )p8jf; z7d;nz zhb; *2zd saun5unw) position with the same speed as it had initially if air resistance is negligible. If air resistance iw5ujzd ;q)b * zz 7zusad )fnhp;n2;8ns appreciable, how will this result be altered?

参考答案:    

标记此题
104#
 
判断题 ( 1.0 分) (组内11/46) 切至整卷模式 搜藏此题  
  An object can have zero velocity and nonzero acceleration at the same timek7x/6f0cgw hd.

参考答案:    

标记此题
105#
 
判断题 ( 1.0 分) (组内12/46) 切至整卷模式 搜藏此题  
  An object can have nonzero velou *mh.v+ow2o 4tbn. zzcity and zero acceleration at the same time.

参考答案:    

标记此题
106#
 
判断题 ( 1.0 分) (组内13/46) 切至整卷模式 搜藏此题  
  An elevator moving fro7bh fl5f94atxw.82l i ftf -zcm the second floor to the fifth floor making no stops along the way8 5b2f.7ti 9z-lfxta4 wfflch has zero acceleration all the time.

参考答案:    

标记此题
107#
 
填空题 ( 1.0 分) (组内14/46) 切至整卷模式 搜藏此题  
  A rolling ball moves from suhpg kclh0e) + x,n:d(l-u,g$x_1=2.7 \mathrm{~cm}$ to $x_2=-7.9 \mathrm{~cm}$ during the time from $t_1=2.4 \mathrm{~s}$ to $t_2=5.3 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

参考答案:    

标记此题
108#
 
填空题 ( 1.0 分) (组内15/46) 切至整卷模式 搜藏此题  
  A particle at $t_1=-2.9 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ is at $x_2=8.1 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

参考答案:    

标记此题
109#
 
填空题 ( 1.0 分) (组内16/46) 切至整卷模式 搜藏此题  
  A person jogs eight complete lapsg / )+y h*y5q-bqldlyt around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.6 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

参考答案:    

标记此题
110#
 
填空题 ( 1.0 分) (组内17/46) 切至整卷模式 搜藏此题  
  A horse canters away from its trainer in a straight line, moving 90 m away cmr2hqddh xx 4cl1bts8n*o.-as0* g 2in 8.4 s. It then turns abruptly and gas0m4 8h s2xg*b*tx-ncdc r2h1l.aqdollops halfway back in 4.6 s. Calculate (a) its average speed  (数值)  $m/s$ and (b) its average velocity  (数值)  $m/s$ for the entire trip, using “away from the trainer” as the positive direction.

参考答案:    

标记此题
111#
 
填空题 ( 1.0 分) (组内18/46) 切至整卷模式 搜藏此题  
  A car accelerates from rgez6m zlvph 3.6s31 y$12 \; m/s$ to $22 \; m/s$ in 4.5 s. What was its acceleration?  (数值)  $m/s^2$ How far did it travel in this time?  (数值)  $m$ Assume constant acceleration.

参考答案:    

标记此题
112#
 
填空题 ( 1.0 分) (组内19/46) 切至整卷模式 搜藏此题  
  A car slows down fromzi5w;)6r+mlkow6lc4 ; nsdh h $16 \; m/s$ to rest in a distance of 65 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

参考答案:    

标记此题
113#
 
填空题 ( 1.0 分) (组内20/46) 切至整卷模式 搜藏此题  
  A light plane must reach a hg -jg0uy):je)-c6 vwj rl8lmm- rv*.)bdyixspeed of $26 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

参考答案:    

标记此题
114#
 
填空题 ( 1.0 分) (组内21/46) 切至整卷模式 搜藏此题  
  A world-class sprinter can burs yvl c77;tkh9i)km y5s1yb.q at out of the blocks to essentially top speed about ; 7 qyikh9vst5 lk.)ambcyy71$10.9 \; m/s$ in the first 11.5 m of the race. What is the average acceleration of this sprinter?  (数值)  $m/s^2$ and how long does it take her to reach that speed?  (数值)  $s$

参考答案:    

标记此题
115#
 
填空题 ( 1.0 分) (组内22/46) 切至整卷模式 搜藏此题  
  A car slows down unifor)ur;dnw o/dof6o 3vgg cx b;/+mly from a speed of $20 \; m/s$ to rest in 4.13 s. How far did it travel in that time?  (数值)  $m$

参考答案:    

标记此题
116#
 
填空题 ( 1.0 分) (组内23/46) 切至整卷模式 搜藏此题  
  In coming to a stop, a car leaves skid marks 92 m long on the highway. Azfw3 wi o14 z;3ciy7iyssuming a deceleration of z7 coy3w3i;izyf14 i w$7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

参考答案:    

标记此题
117#
 
填空题 ( 1.0 分) (组内24/46) 切至整卷模式 搜藏此题  
  A car is behind a tructg1+6h wly2rqc k+jwhq3+ di6k going $25 \; m/s$ on the highway. The car’s driver looks for an opportunity to pass, guessing that his car can accelerate at $1.0 \; m/s^2$. He gauges that he has to cover the 20-m length of the truck, plus 10 m clear room at the rear of the truck and 10 m more at the front of it. In the oncoming lane, he sees a car approaching, probably also traveling at $25 \; m/s$. What is the closest distance of the approaching car that he can still sately make the attempt to pass the truck? (without hitting the approaching car).    $m$

参考答案:    

标记此题
118#
 
填空题 ( 1.0 分) (组内25/46) 切至整卷模式 搜藏此题  
  A runner hopes to complete the 182, g/-rbvzv.6bvyo ekg 5iux6 w0 xex0,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then acceleratub-vzo vr/ xx06 w5 6i gygk,.8ev2ebxe at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$

参考答案:    

标记此题
119#
 
填空题 ( 1.0 分) (组内26/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the top of a cliff. It hits the ground below aft9 wed/u lu*xz+er $2.34 \; s$. How high is the cliff?  (数值)  $m$

参考答案:    

标记此题
120#
 
填空题 ( 1.0 分) (组内27/46) 切至整卷模式 搜藏此题  
  Estimate (a) how long it took a stone to fall straight down from the top olgs103ts5dt rl 9l . bzbngd-:f the Empire State Buildingztg rt - 5:.gdsl3snbd0l b91l (379 m high)  (数值)  $s$, and (b) its velocity just before landing?  (数值)  $m/s$

参考答案:    

标记此题
121#
 
填空题 ( 1.0 分) (组内28/46) 切至整卷模式 搜藏此题  
  A baseball is hit nearly straight up into the air with a szd.zyx6bx n: +3zb+ zqpeed of $17 \; m/s$. (a) How high does it go?  (数值)  $m$ (b) How long is it in the air?  (数值)  $s$

参考答案:    

标记此题
122#
 
填空题 ( 1.0 分) (组内29/46) 切至整卷模式 搜藏此题  
  A ballplayer catches a ball 2.5 s after throwing it verticalkw2* mhmu6 l)xly upward. (a) With what speed did he tm*62 mx)l wkhuhrow it?  (数值)  $m/s$ and (b) what height did it reach?  (数值)  $m$

参考答案:    

标记此题
123#
 
填空题 ( 1.0 分) (组内30/46) 切至整卷模式 搜藏此题  
  A helicopter is ascending vertio4f6y mi.db; bcally with a speed of $5.06 \; m/s$. At a height of 89 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground?  (数值)  $s$
[Hint: The package’s initial speed equals the helicopter’s.]

参考答案:    

标记此题
124#
 
填空题 ( 1.0 分) (组内31/46) 切至整卷模式 搜藏此题  
  A stone is thrown vertically upward with a mu71cew;*/ ok( ut-skmtvk ;z speed of $15 \; m/s$. (a) How fast is it moving when it reaches a height of 8.4 m?  (数值)  $m/s$ (b) How long is required to reach this height for the first time?  (数值)  $s$ (c) How long is required to reach this height for the second time?  (数值)  $s$

参考答案:    

标记此题
125#
 
填空题 ( 1.0 分) (组内32/46) 切至整卷模式 搜藏此题  
  A falling stone takes 0.14 s to tr 1jug0 j9;5uz6zq,qmphqzf,javel past a window 2.2 m tall. From what height above the top of the window did the ston, uj 5j,jq1;zzf gzqq96hmup0e fall?  (数值)  $m$


参考答案:    

标记此题
126#
 
填空题 ( 1.0 分) (组内33/46) 切至整卷模式 搜藏此题  
  A rock is dropped from a sea cliff6b3 cy ya7 .o9l1 tb9z;lr(apc;nj-fm(w zhuz, and the sound of it striking the ocean is heard 2.yb6oaf1 j3c m(byan9l7zp9zcu;hr tz(l. -w;8 s later. If the speed of sound is $340 \; m/s$, how high is the cliff?  (数值)  $m$

参考答案:    

标记此题
127#
 
填空题 ( 1.0 分) (组内34/46) 切至整卷模式 搜藏此题  
  A stone is thrown verticall nyd9r)q:10m 8k)ztv pp.y hoxy upward with a speed of $10 \; m/s$ from the edge of a cliff 42.5 m high (a) How much later does it reach the bottom of the cliff?  (数值)  $s$ (b) What is its speed just before hitting?  (数值)  $m/s$ (c) What total distance did it travel?  (数值)  $m$

参考答案:    

标记此题
128#
 
填空题 ( 1.0 分) (组内35/46) 切至整卷模式 搜藏此题  
  A baseball is seen to pass upward by someone on the 9th floor (28 m4ic9 toe 6xay) above the stre4ec)x at9y6oiet) with a vertical speed of $9 \; m/s$. If the ball was thrown from the street, (a) what was its initial speed?  (数值)  $m/s$ (b) what maximum altitude does it reach?  (数值)  $m$ (c) how many seconds ago was the baseball thown from the street?  (数值)  $s$ (c) In how many seconds will it reach the street again?  (数值)  $s$

参考答案:    

标记此题
129#
 
填空题 ( 1.0 分) (组内36/46) 切至整卷模式 搜藏此题  
  The acceleration due to gravity on the Moon is about one-svo+tt.alfz +0 ixth what it is on Earth. If an object i.flaoz+v t+ t0s thrown vertically upward on the Moon, how many times higher will it go than it would on Earth, assuming the same initial velocity?    $times$

参考答案:    

标记此题
130#
 
填空题 ( 1.0 分) (组内37/46) 切至整卷模式 搜藏此题  
  A 95-m-long train begins uniform acceleration from rest. The front of the t /ks*mnq jr66 /2wgh q4yk10jdepktr .rain has a speed0sqpr4jmk*/j 6wt k.6r eykqh21gn /d of $12 \; m/s$ when it passes a railway worker who is standing 128 m from where the front of the train started. What will be the speed of the last car of the train as it passes the worker?  (数值)  $m/s$

参考答案:    

标记此题
131#
 
填空题 ( 1.0 分) (组内38/46) 切至整卷模式 搜藏此题  
  A fugitive tries to hop on a freight train traveling at a c3; yzg a(luowqmvf0( -onstant speed of $6.0 \; m/s$. Just as an empty box car passes him, the fugitive starts from rest and accelerates at $a=4.0 \; m/s^2$ to his maximum speed of $8.0 \; m/s$. (a) How long does it take him to catch up to the empty box car?    $s$ (b) What is the distance traveled to reach the box car?    $m$

参考答案:    

标记此题
132#
 
填空题 ( 1.0 分) (组内39/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the roof of a high building. A second stone is droppr*8qv0 y)kl qaed 1.25 s later. How far apart are the stones when the second one h k80lqy)va* qras reached a speed of $12 \; m/s$?  (数值)  $m$

参考答案:    

标记此题
133#
 
填空题 ( 1.0 分) (组内40/46) 切至整卷模式 搜藏此题  
  A race car driver must average-:bc 3e1 jevl(ljayu i7vn4 l; $200 \; km/h$ over the course of a time trial lasting ten laps. If the first nine laps were done at $189 \; km/h$, what average speed must be maintained for the last lap?  (数值)  $km/h$

参考答案:    

标记此题
134#
 
填空题 ( 1.0 分) (组内41/46) 切至整卷模式 搜藏此题  
  A rocket rises verticall4xr4z s;urr6 dy, from rest, with an acceleration of $3.2 \; m/s^2$ until it runs out of fuel at an altitude of 1200 m. After this point, its acceleration is that of gravity, downward.
(a) What is the velocity of the rocket when it runs out of fuel?    $m/s$
(b) How long does it take to reach this point?    $s$
(c) What maximum altitude does the rocket reach?    $m$
(d) How much time (total) does it take to reach maximum altitude?    $s$
(e) With what velocity does the rocket strike the Earth?    $m/s$
(f) How long (total) is it in the air?    $s$

参考答案:    

标记此题
135#
 
填空题 ( 1.0 分) (组内42/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the roof of a building; 1.75 s after that, a secoog* ),g xq9dq.gbag,tytk-zxu*m2r9 nd stone isk qg goyttz2- .g9,ambu9,)xd* r qx*g thrown straight down with an initial speed of $25 \; m/s$ and the two stones land at the same time.
(a) How long did it take the first stone to reach the ground?  (数值)  $s$
(b) How high is the building?  (数值)  $m$
(c) What is the speed of the first stone just before it hit the ground?  (数值)  $m/s$
(d) What is the speed of the second stone just before it hit the ground?  (数值)  $m/s$

参考答案:    

标记此题
136#
 
填空题 ( 1.0 分) (组内43/46) 切至整卷模式 搜藏此题  
  If there were no air resistance, how long wow7zc;wxe +a a4h-;/9 dsd jn1g(5ph ovadd-xfuld it take a free-falling parachutist to fall from a plane at 4440 m to an altitude of 350 m, where she will pull her ripcord? What would her speed be at 350 m? (In reality, the air resistance will restrict her speed to perhaps muznj x4-a ws 1;/5w97hoadca d( -d;fgvdpxeh +st lower value)  (数值)  $m/s$

参考答案:    

标记此题
137#
 
填空题 ( 1.0 分) (组内44/46) 切至整卷模式 搜藏此题  
  Bill can throw a ball verticall yivng,( +3wdsy at a speed 1.4 times faster than Joe can. How many times higher will Bil(3,s+yndvg wi l’s ball go than Joe’s?  (数值)  $times$

参考答案:    

标记此题
138#
 
填空题 ( 1.0 分) (组内45/46) 切至整卷模式 搜藏此题  
  You stand at the top of a cliff while your friend stands on the grou0s:,a1a jnvw7 eom r(qnd below you. You drop a ball from rest and see that it takes 1.1 s for the ball to hit the ground below. Your friend then picks up the ball and throws it up to yoewv :(qan70m1j, ors au, such that it just comes to rest in your hand. What is the speed with which your friend threw the ball?  (数值)  $m/s$

参考答案:    

标记此题
139#
 
填空题 ( 1.0 分) (组内46/46) 切至整卷模式 搜藏此题  
  Two students are asked to find the height of a particular building. Tg j+-rbty 1f0 nbw(trxtt 7,)shey take a stone to the roof of the building and drop it off, )yt(b7nt- xrt1s,bj 0tr w +fgtiming its fall. One student reports a fall time of 2.0 s, and the other, 2.3 s. How much difference does the difference in time make for the estimates of the building’s height?  (数值)  $m$

参考答案:    

  • 答题人:
  • 总分:149分 及格:89.4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 139 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, 2024-10-7 06:40 , Processed in 0.634692 second(s), 302 queries , Redis On.