Is it possible for an object mf plw6y0a 5unq i:ab*ptc.b14 oving with a constant speed to accelerate? Explaibwipaf 5ba06n:u pyt *4 q1lc.n.

  Consider a particle moving with constant -svepk l;;jv4mr+ w 5aspeed such that its acceleration of constant magmvj-r;kl ew4p+v5; sanitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed9uprduxd4 tede6u9 59. Compare the direction of the object's velocity and acceler64ddt 5reuu99eduxp 9 ation vectors.

  When an object experiences uniform circular motion2x+qr/-h ae xui syok.u7 e k*atj4h19, the direction of the acceleration is1e2xk7s+q.a 9 ox*4 j/hhueyukr-i a t

  Consider a particle moving wi ho d1dfazs+i -:5y)pwpy1fd:th constant speed such that its acceleration of constant magnitude sz: 1pf5oi:h d-)yyp+d d1wfais always perpendicular to its velocity.

  What type of acceleration doey gu.6i*. srnos an object moving with constant speed in a circular path experiencei. osu.yr*6 ng?

  What force is needed to make an objec f9z5utm ),ryql mw6*gt move in a circle?

  When an object experiences us*clz- caumc.6bk9f+gev; 3q niform circular motion, the direction of the net forc6c+s.*f9 va-z3ukg ;mcb eq cle is

  A roller coaster car is onut)k d3gv0+fo yz7p 76jut kx;o(g*qu a track that forms a circular loop in the vertical plane. If the ogvy0t t)+k p(fod* xquu73z7;6g kj ucar is to just maintain contact with track at the top of the loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track thatc bx2v* /ngrl)csjd 6*3l*lxx forms a circular loop (radius = r) in the vertical p6c*vxrsx jlg /3n*)x lbc* ld2lane. If the car is to just maintain contact with the track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a verticq e;i:.apvz ormdzxx 8m9b2 0 3eg4lu8al dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its l3am:oxx2epz 8 ml9r4dbv .i8zuge; q0owest point, the force on him is

  A coin of mass $m$ rests on a turntable a distance $r$ from the axis of rotation. The turntable rotates with a frequency of $f$. What is the minimum coefficient of static friction between the turntable and the coin if the coin is not to slip?

  A car goes around a curve of radiuy.7 /klvy)xujs $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radius r at a consa o;d)dl ie h: :anwb2;vkm eu85q(hk.tant speed v. Then it goes around the same curve at half of the original speed:h.qdalwno:ee m8ba;i;kkv( 2 5)dhu . What is the centripetal force on the car as it goes around the curve for the second time, compared to the first time?

  A car goes around a curve of radius r at a cw-plfg)46 7yqw8h fr bonstant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, compared t8 74w -wprqh 6bfgfly)o the first?

  A car of mass m goes around a banked curpzl)*pcd0 1r )rm9 aunve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal )0*1 lrd9 rpz a)mncupforce on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, but one hat;l2n /ms8 h3ynrti d:s twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius curve is v. What is the safe speed om23 htr:sn 8dyl/tin;n the larger radius curve?

  The banking angle in a turn on the Olympic bobsled yvb859/don0 dz 4 fnwdtrack is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentiwn9 8/5yz4b vndo df0donally "climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object moving around a circular path to have k .2q58mr7p h swifn*vboth centripetal and tangential accelera npmf8.sri hw *2k5q7vtion?

  The gravitational force between two objecax*+7n+v4dqfm;k fv1o : wn v* u,uhkrts is proportional to

  The gravitational force between two objects is ir (:ev2xc s-t8dq 1tkbnversely proportional to

  Two objects attract each other gravitationag4: 1rsu-tdr o- zvcp(lly. If the distance between their centers is cut in half, the gravitationrcs:- 1 -4r(zvtgdpo ual force

  Two objects, with masd r oujfg1 wc-0q:2;viyawf+kgyf3 *4 ses $m_{1}$ and $m_{2}$, are originally a distance r apart. The gravitational force between them has magnitude F. The second object has its mass changed to 2$m_{2}$, and the distance is changed to r/4. What is the magnitude of the new gravitational force?

  Two objects, with ma24echaz3lq9 mmqs n)9sses $m_{1}$ and $m_{2}$, are originally a distance r apart. The magnitude of the gravitational force between them is F. The masses are changed to 2$m_{1}$ and 2$m_{2}$, and the distance is changed to 4r. What is the magnitude of the new gravitational force?

State Newton's law of univer+ 8 ncqpi;riw b/ f9+f/0pvakdsal gravitation.

  Compared to its mass on : zrq.t-vi; -zfie6oa s/,b)r c*vejn the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on 70fqork yl6t 9Earth. An object oykr7t6l9fqo 0 f mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves awank:qp84y;nt *v(so,uqfxp 5; ufk5 dd y from the Earth's surface, the rocket's weight

  A spaceship is traveling to the Monzf cy1/0c/vpon. At what point is it beyond the pull of Eartv cfcynz/p1 /0h's gravity?

  Suppose a satellite were orbiting the Earth just above the surface. Whu 25fpcc.k hxkp0-o 6oat is its centripetal accelera.pcu kokx 60 fo5hc-2ption?

  A hypothetical planet has a mass oll +ac+s(4bza f half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due toac+b4al(z+l s gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what 80ltmd kw;* e-h:gxz6qqdz4:w ;yafpit is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass comwwz: 4xa:8mqdpkl; z0yetq f- 6;g *hdpared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice tj *.)7+fyrkbns ;x ehlhe radius of planet A. If planet A has mass m, what is je7y+;.lsxb ) rn*khf the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass k*0nm s.zr(erof planet A. If planet A has radius r, what is the radius sne.(*r z0k rmof planet B?

  Consider a small satellite moving in a circulah:.y zw1rmtm o 6rkpz(y 9/bc7r orbit (radius r) about a spherical plaopr( z7/hr cb:1yw6k. tymzm9 net (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of safbv cr8o j,;dy+f,j,i.sv it /tellite B, and rotates in the same orbit. Compare the vtfrvy, j,.+coi,;fijd/ b8s two satellite's speeds.

  A person is standing on a scale in an elevatora lt dg2wbn.;3 accelerating downward. Compare the reading on the scale to t ;2ga3d.blt nwhe person's true weight.

  Who was the first person to realize that the planets move in elliptical paths ar7chz(.czqis bwn,3 -jound the Sunc-, 3hwsbj z7nc (zq.i?

  The speed of Halley's mqzc 3d 6li;rh.kx gaby (-9hledk+s8,6uu a )Comet, while traveling in its elliptical orbit around the Sunz,dhyl+q .r )lak ku-6eah;c bi3 u8ds (x96gm,

  Let the average orbital radius of a planet be R. Let the orbital period f;djm zk h63+7rchp q2/5ptrnbe T. What qktfp/qhj25r;cz rpmh +3 d7n6uantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, with 4det5a41kq;n hq* ogh 4:hxysthe same orbital diameter as the Earth around our Sun. If th:1e xh kgq 4hot5qd4ys*nh4;aat star has 4 times the mass of our Sun, what will the period of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from the Ear npbjik3f l:zav)9 kt.j*)l1eth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the astena )3:jtz v*lp.blk9k iej) f1roid's average distance from the Sun?

State Kepler's laws.(/a5n-cb*hg-4qp z4ta;xwj n6 tmlbrqrd l3 (

  List the four fundamental forces icp k.d+/d1xf nn nature.

  An object moves with a constant speed of 30 m/s on a circun0hrd; 4mt 9azlar track of radius 150 m. What is the ac mthr9d;0anz4celeration of the object?

  The maximum speed around a level curve is 30.0 km/h. What/*2zk oie+wx x is the maximum speed around a curve with twice the radius? x+xoe*zkwi2 / (Assume all other factors remain unchanged.)

  What is the centripetal acalii5 (z rj29- py; l-imwdbw3celeration of a point on the perimeter of a bicycle wheel of b pl3-wid (rm9;wyiz2la -5 ijdiameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis.ee-rjmg,,5dymgx,db8 5 /uu j;stj 0s What is the centrismgy5 g ,e0 jsb, xud8,-mjdrju/et;5petal acceleration?

  How many revolutionsmuc l ()p/pn-m per minute must a circular, rotating space station of radius 1000 m rotate to produce an n)u-cmpp( / lmartificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass u/ ju2iqdp-tyd95 v3gel/ bf- of 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force onb -/u2y tf5 vieldp3gdqu /9-j the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The s93 wah t,bqe4system is whirled in a horizontal circular path. If the maximum tension that the strin49wtbas ,e 3qhg can withstand is 350 N. What is the maximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a ve u: /tj2gwn4ahrtical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The stone's speed at tuw24j/ g:ah nthis point is given by

  A stone, of mass m, is attache7ustl 4mc bo5f/xo8,hd to a strong string and whirled in a vertical circle of radius r. At the exact bottom of ,s78hu4c5x/ o loftbm the path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an accelou3c+ekn5ph - 8gnou f4v))jueration of 4g when pulling out of the dive. What is the radius of curvatojv 54)uph83fgcn u+u)k o-neure of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which:qpv * h-xf53jjnh +rm the center of the loop is beneath him) of radius 3200 m. At the tqn*x: hphm f3 jvr+-j5op of his loop he is pushing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times hish9qqntr* sis; 7 sa/5hy;fnp-cu p/* d weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertic;naqr** 7s/-pq/f ph u;s5 ndih9 ycstal dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s roz,b;1xamq h3-ao t0anitnd8m4f7-uz6lwi 2junds an 80-m radius horizontal curve with the tires on the verge of af7 l m6o iua,z8iahtx -w1tn;qdjzb0m -4n32slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m w-h fyx1s5wv/gy(xt- z 6 zzis-ith a speed of 20 m/s. The centripetal force provide-/z iz5xyf z6-w1(xys ht -sgvd by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat cur1j) r8501 quuzh ntbfyve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for then51 fqu rj hbyt)1uz80 car to make the turn?

  A car is moving with a9 b 2 nr4lis, -virxd(2hw(wdn constant speed v around a level curve. The coefficient of friction between the tires and the road is 0.sd -ln(dv i,irn9h w2x(wbr42 40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for ahr- pm4u 0jw8o rlh:a;ah,l0 jn Olympic bobsled to negotiate a 100-m radius0 8lma40jhho wr- ah ;ul,r:jp turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked;. k2x 1fmqnc1+ioy vwq *-wdn at a $45^{\circ}$ angle. When a bobsled rounds this curve at the curve's safe speed (no friction needed to stay on the run), what is its centripetal acceleration?

  A frictionless curve of radius 100 m, banked at an angl2t0eucj )mn rs1-f+ene of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked atl7hvxzlz /duim 7d w)8u8ofrb (15 na) $45^{\circ}$. Suppose that an ice storm hits, and the curve is effectively frictionless. What is the safe speed with which to take the curve without either sliding up or down?

  A 175-kg ball on the end of a string is revolving uniformly in a6++z k-uq0-zp ua9sklasfnle l,lo71a8i em / horizontal circle of radius 0.50sua1z,f/aea zl79m8ks +l -kiqpl 0noeu 6-+l0
m. The ball makes 2.00 revolutions in a second. (only fill in numerial value in the blanks)
(a) Determine the speed of the ball.    $m/s$
(b) Determine the ball's centripetal acceleration.    $m/s^2$
(c) Determine the force a person must exert on opposite end of the string.    $N$

  Starting from rest in the pit area, a race car accelp 6 iczpk4q12terates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (onl6pcp1 z42ti qky fill in numerical value in the blanks)
(a) Calculate the tangential acceleration.    $m/s^2$
(b) Calculate the radial acceleration when the instantaneous speed is equal to 30 m/s.    $m/s^2$

  The hydrogen atom consists of a proton of masnscqbm t.1 .o9s $1.67 \times 10^{-27} \; kg$ and an orbiting electron of mass $9.11 \times 10^{-31} \; kg$. In one of its orbits, the electron is $5.3 \times 10^{-11} \; m$ from the proton. What is the mutual attractive force between the electron and proton?

  What is the gravitation+e n4/auhdjsugrw ot / 73 3wwq:y1-fbal force on a 70-kg person standing on the Earth, due to the Moon? The ma/awwr+3h3 w:d1ftqby- gn4s/u j7o uess of the Moon is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force behbb9v3 x-tjond 9(wd* / fyrj 3k3rg2ozf9ny; tween two masses is F. If the masses are moved to half of their initialbdhf3;o2ty9 bjnjvg(3 d yr rz-9*kxn 9wof/3 distance, what is the gravitational attractive force?

  For a spacecraft going from thmyxg+xr 37hd a9h )6ine Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and tnd )mhx 79rxy6g+3h aihe Earth cancel?
Earth's mass: Me = $5.98 \times 10^{24} \; kg$ the Sun's mass: Ms = $1.99 \times 10^{30} \; kg$
Earth-Sun distance: r = $1.50 \times 10^{11} \; m$

  The mass of the Moon is (3lk.br0 onwl$7.4 \times 10^{22} \; kg$ and its mean radius is $1.75 \times 10^{3} \; km$. What is the acceleration due to gravity at the surface of the Moon?

  An astronaut goes out for a "space-walk" at a distance above tzge3 3//r i uqymdnh81he Earth equal to the radius of the Earth. What is her ag/euqz/ hmni dr8331ycceleration due to gravity?

  The radius of the Earth yjp d4kl:l;o3 sf:ch ;is R. At what distance above the Earth's surface will the acceles4 o c3kh ;fld;yl::pjration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a d zhq: pt9 6:3n/uyjesvistance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of :q jnvehtys9/u:3 z6pgravity on the surface of Mars, is

  At a distance of 14000 km from some planet's . dn mx);,5rijod bd1zcenter, the acceleration of gravity is ;zbd5)d1,odjrm . inx$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surfacs-y;9ncke.il e of the Earth. The Earth has radius r. If the object is raised to a hee;.lk i-n9 csyight of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes fi oan+ 1se q5i)b4x+lvrom sea level to an alta1+l4o 5isqi be )xnv+itude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satelrlj+7bt4ud d2lite of mass 100 kg is at a point 3r above the Earth's surface. What is the satelbt 2d 4dl+urj7lite's weight?

  A spherically symmetric pte.j 2b7,yqpo/uy 18l xzlu7 h:kfcd.y9-u xylanet has four times the Earth's mass and twice its radius. If y k l oq.8,ycu: d7pujb7x9hyx/e2u.lt1zyf -a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and9td*0jwpy jni2-yzzh+ ( +lmx Sun all lie on the same line, with the Earth between the Moon and t +dy(ythj +j 29z0pnlix-zw*mhe Sun. The Moon has a mass of $7.36 \times 10^{22} \; kg$; the Earth has a mass of $5.98 \times 10^{24} \; kg$; and the Sun has a mass of $1.99 \times 10^{30} \; kg$. The separation between the Moon and the Earth is given by $3.84 \times 10^{8} \; m$; the separation between the Earth and the Sun is given by $1.496 \times 10^{11} \; m$.
(a) Calculate the force exerted on the Earth by the Moon, its magnitude is    $\times 10^{20} \; N$, its direction is  ----待选择----towardsaway from  the moon.
(b) Calculate the force exerted on the Earth by the Sun, its magnitude is    $\times 10^{22} \; N$, its direction is  ----待选择----towardsaway from  the Sun.
(c) Calculate the net force exerted on the Earth by the Moon and the Sun, its magnitude is    $\times 10^{22} \; N$, its direction is  ----待选择----towardsaway from  the Sun.

  A 2.10-kg brass ball is transported tr7d4 k wvr;kg5o the Moon.
(a) Calculate the acceleration due to gravity on the Moon.    $m/s^2$ (The radius of the Moon is $1.74 \times 10^{6} \; m$ and the mass of the Moon is $7.35 \times 10^{22} \; kg$)
(b) Determine the mass of the brass ball on the Earth    $kg$ and on the Moon    $kg$
(c) Determine the weight of the brass ball on the Earth    $N$
(d) Determine the weight of the brass ball on the Moon    $N$

  A satellite is in a low circular orbit about the vg:-s)xzur /qhq1x a) Earth (i.e., it just skims the surface ofxr -/uahxq))szgqv :1 the Earth). What is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., itodpq jw oy u 7a7/m7r9,dl+dx( just skims the surface of the Earth). How long d 7u+d9(7l rwajqy,pmod/ d 7xooes it take to make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 2q5 p8 ct1im:jq)ipf nqk1)1 vg big0h;30 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radiusp8qi:gt 0ifq ig1cqjn ;5k 1m v)1)hbp of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, hbku:iqoc6*pk .n: 1kxas an orbital diameter of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orbits the planet with a ray1ad42a acemwcpx4 q9ovy7i4k1,. le dius of $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a planet in nearly circular orbits. Moon A haele3i8mc+.c c 8i .zv7az pa:xs orbital radius r, and moona.z cc3czi 8iae.p:e8vx+l7 m B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is4c m fj(v tn2f- ;9yems:u svvya/u+x/ $7.78 \times 10^{11} \; m$ from the Sun. How long does it take for Jupiter to orbit once about the Sun? (The distance from the Earth to the Sun is $1.50 \times 10^{11} \; m$.)

  It takes the planet Jrj84tuwnvu .b0 8evp (upiter 12 years to orbit the Sun once. What is the average distance from Jupiter to the St4nru. vpj8 (webv80u un? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)