Is it possible for an object movkmi0onwma/ qk 5;*ey- xj n+9ping with a constant speed to accelerate? Explai 0a* k9 /wyjok i+xe;-nnpm5mqn.

  Consider a particle moving with constant speed such tjbz *3x xm83ulcj7dr: hat its acceleration of constant magnitude is always perpendicular to its xclb8x:d*z mj3u 7j3rvelocity.

  An object moves in a circular path at a constwcc;8 j:3sps8bd ye (cant speed. Compare the direction of the object's velocity and acceleraticbc 38 (ssy8e:w;jdp con vectors.

  When an object experiencesjr,mv)gxb8v3j ;; tjd uniform circular motion, the direction of the acceleration i38 r mbx);,djtg ;vvjjs

  Consider a particle moving wit09 14jzok joeph constant speed such that its acceleration of constant magnitude is always perpendicular to its velocitoe1zk 4po9jj 0y.

  What type of acceleration does an objqc33u yj24dnp ect moving with constant speed in a circular jqy 3uc432dpn path experience?

  What force is needed to+7x3l;hhsfn ii8 qp-k(m 1 1vt 6kp0phgq 2rrx make an object move in a circle?

  When an object experiences )x3h77gbud u mj:lbz66l nrf5 uniform circular motion, the direction of the net force is7ru7:5mg6dxjf l3l )ub6zbnh

  A roller coaster car is on a track thats 8xro*p i/qu ngtc30: forms a circular loop in the vertical plane. Ic orqtxs *ni:8g0/3up f the car 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 that forms,bz .m 2*fukys a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of the loop, what is fbsz2 ,*.uk ymthe minimum value for its speed at that point?

  A pilot executes a verticp3 yf*k o b;)how4k-tc c90vpmal dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on p0 ymkopf cc9; tb*)w-3voh4k 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 radi,ei b.uz9te8 uus $r$ 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 constant speedm*b;4 i 2a8ikr2 anbbu v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around the curve for the second time, compared to the first tim b; r4 kb2biinua8*m2ae?

  A car goes around a curve of radius r at a constant 34x v8l cuat:6fmxjw- speed v. Then it goes around a curve of radius 2r a4uac:jvft- m3 lwxx86 t speed 2v. What is the centripetal force on the car as it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with speed -+fi:- ndgwt *imxo*d v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the c-i-+w* :iddf xmtgon*ar from the road is equal in magnitude to

  Two horizontal curves on a bobslpao0uhr a mj vtk5.f 4a.yb06h 0l7,jved run are banked at the same angle, but one has twice the radius of the other. The safe speed (no friction neede0lom. .7j0 aakfvv4ha0 b ryp,hjtu65d to stay on the run) for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsleudl 5cm* e.oosj+ ()je(jh6akd track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally m j.el( o6juk(oehca *5j )d+s"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 both centrzrgpr 5lv1.l nm+fi67+* slc.kr fyt0ipetal and tangenti* .s05ff+rlinrykz.6 vlclp 1 +7gtrmal acceleration?

  The gravitational force bm,8 9pzxa+roivw y k,5etween two objects is proportional to

  The gravitational force becsgvy 8lw:/l(eip 26f tween two objects is inversely proportional to

  Two objects attract each other grw.l3 g2 hd/3ob8vr 7k)ldwo6 wif3rxqavitationally. If the distance between their centers is cut in hg63d2bi/oh7ldfr wwr x)w3 kl 83oqv.alf, the gravitational force

  Two objects, with masses xnzw/ u *x:u sggq8qtx9,b/3h$m_{1}$ 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 masse:c9/ac6f tk))hvrc s qs $m_{1}$ 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 universa,jey fhzt -4yyw9p 6;ml gravitation.

  Compared to its mass on the Earth, the mass of an object on the Moox1bbka+ crhr ckuaje9 97-)o: n is

  The acceleration of gravity on the Moon is one-sixth7x e8squs5u r7,w+cf nnor s1p r6u..q what it is on Earth. An object ofn 5r1.c rofns us ure7s6,u.+7x qq8wp mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surfac*0j:szmx )2,elsnlq k.ovc 9qe, the rocket's weight

  A spaceship is traveling to the Moon m;cywq4qfk loy* .04a. At what point is it beyond the pull of Earth's gravity?cfm lw*yq0a ;4.oq4y k

  Suppose a satellite were orbiting the Earth just above the surfaceh 15xd kggqn:5. What is its centripetal acceleratio k1qgxn5:5 hgdn?

  A hypothetical planet has a mass of half that of the Earth and a radius of jv1/s7+ g oz nryao6m;twice that of the Earth. What is the acceleratiojn6 ;z+mv/r 7gao 1oysn due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the M6n (omcroev o /y2t83toon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to tho( o3otn2v cmry86et/e Earth's?

  Two planets have the same surface gravity, but planet B has twice the radius o* oq)5rybu6t9)o xcrgf plane9bo*otqu5xgc r)6r y)t A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet uwt- v9ha e)uyg-, mtgt*i*8; lb o5pyB has twice the mass of planet A. If planet A has radius r, what is the rygtuie89bt;*o p -t)gu lw5v ,*-mhayadius of planet B?

  Consider a small satellite moving in a cir uimw.o /i ec9k:b0y5ycular orbit (radius r) about a spherical planet (mass M). Which expression gives this satelli05i ku/.wy ibcye9o: mte's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the sam hfm9x7bg,t3y e orbit. Compare the two satelli9h tmy37 gxf,bte's speeds.

  A person is standing on a scale in an +7j6wv e/ lbgxelevator accelerating downward. Compare the reading on the scale to 6vbg l+exw/j7the person's true weight.

  Who was the first person to reali*8s pz ky;1sxrze that the planets move in elliptical paths around the Su;yxs k8rp z1*sn?

  The speed of Halley's Comet, while t xi.2- a6mbkucraveling in its elliptical orbit around the Sun,xbik-a6c2m . u

  Let the average orbital radius of a planet be R7lydd3o taxk w5,vd;:z7c6; 9et i cvd. Let the orbital period be T. Wh 7;v 7cy3did:k l6oaztdxw95;dvtce,at quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy f6 0fvqh-ocdmp-v:-o,iv 9 j mAndromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of our Sun, what will the period of revolution of that new planet be, compared to the Eardq ocmfo :vm-,-jvf i9-0h 6vpth's orbital period?

  The average distance from the Earth to the Sun is defined as one "astronomical u3*uklo mu4- r;gn;gwn nit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroidgr*3-4nlmokwn g ;uu; 's average distance from the Sun?

State Kepler's laws. 86 l8bzvxo -pnv9yqi9

  List the four fundamental forces in 2 grvz x(umg4 a:*xd-1thwgvvnlp9 :0nature.

  An object moves with a constant speed of 30 m/s rp8-vfx51 q/tbl bqi6on a circular track of radius 150 m. l6/qbvb qfx1ri8 5p-tWhat is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum spe..gu 18il)n lraumvu6 ed around a cui )1 lrmu.va86nu. uglrve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicsel4z8nmjq7 rb .ox44 ycle wheel of dib l rxs748em zjo4q4.nameter 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 cwwe.j,t.o-o ym3i s12 9vknm from the axis. What is the centripetal accelerationm.ysm19 t,ev i c2k 3-o.wonwj?

  How many revolutions per minute must a circular, u.f0 y3a 0srdmz:gmd/ rotating space station of radius 1000 m rotate to pry0d da3fu g 0:zmrsm/.oduce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius tu h gjtl4ryqvdtft(t-mn;,00( rn at 96.5 km/h. What is the ceqvm( t t0n(-; ftj,rl htg04dyntripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a8s1rv5bm;0md dva 4y q 1.0-m string. The system is whirled in a hor0 1dyqs 54v8mv bar;dmizontal circular path. If the maximum tension that the string 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 vertical cir;xpod *bp o;(vsrx *w*cle of radius r. At the exact top of the path the tensi * p p;rwxxo**;bsovd(on in the string is 3 times the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in a vertical lzvgk*f6l,s, 8ra 9sads;5huku ,:er circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stonekvk6 dsl5,u,8ez:9gas shrr *,uf;l a's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an accelera 1d i6p4/hv jn8a;cygmtion of 4g when pulling out of the dive. What is the rad8ncj1p/md6g y ;v hi4aius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertizy *u0bo5nzu0r3k n +//uuim ncal loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his3yuunn o/mn05i kb /0zr+uzu* seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand j9visotuotu(o5h8 s i n:w(;( is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a 9(ovs(wo uoi:jtuin8; s(t5hspeed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal cuf5+rqacyr0r ( rve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient of friction between the car's +5(a rcfrq y0rtires and each road surface.)

  A car is negotiating a flat curve of r: a5ueijqr,9tadius 50 m with a speed of 20 m/s. The centripetal force provided by fricti:u9rija 5,e qton is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 50 m -7rmjhgwiy* 16bnz xs e3x -x,hf e9c)at a speed of 14 m/s. What must be the minimum cof9-1r6 wmnj-e)xcx ,sh igehy*x3bz 7efficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around 3bxj uq.- gp;ia level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay ob-.3pi gqj ;uxn the road?

  What minimum banking angle b9jxkta e+ 5)his required for an Olympic bobsled to negotiate a 100-m radius turn at )9bha5 kj x+te35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 9k;pfnz*j-8 hzsf )+wjv1dmwf*efr 5a $45^{\circ}$ 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 bf x5)b5mu:bvangle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked ;tst / lvxhp76i0urp ;at $45^{\circ}$. 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 stmyyt(njdb4 1+1f1k qen; n7o 4 bate3aring is revolving uniformly in a horizontal circte ktebajnqd41n3o+y41 n a7; m (1bfyle of radius 0.500
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 zf6w w(em2ztj.vryob74 +ct ,kus a25 car accelerates at a uniform rate to a speed of 45 m/s in 15 s, ms(b7w jwkc5,v+4teroz 2u2.ty6m a z foving on a circular track of radius 500 m. (only 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 consist 9f2fnjuf h4 r1,bcky*s of a proton of mass $1.67 \times 10^{-27} \; kg$ 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 gravitational force on a 70-kg person standing xco1:ch v,b,eon the Earth, due to the Moon? The mass of the Moon:c1 vxb,o,che is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between tefw: iuc5 mj* rgs +3e66fp-zhwo masses is F. If the masses are moved to half of their initial distance, what 5mwp ezh s*3i c6rue: g-j+6ffis the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from tlkja6at8(z9h:vvunbh 0 b+1mtlvn*6wv ; jt8 he Earth will the gravitational forceb h0awt6ujv 1n8th l;v kb8+9(nva*tlv:z j6ms due to the Sun and the 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 csb69 14vx a a8ow;vw+po2-pgvw7wi e$7.4 \times 10^{22} \; kg$ 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 "s hgs9.x *on6ctpace-walk" at a distance above the Earth equal to the radius of the Earth. What is her acceleration duhn.*9 stcxog6e to gravity?

  The radius of the Earth is R. At what distance above the Earth's sh0 (k 2d+:j ip,ikngdburface will the acceleration of g(d : gjnkbh2ip+k i,d0ravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above /d49b4kc4iax/ lmkeo its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Marsce4dmi4/4ka9 ol k/xb, is

  At a distance of 14000av89nvjn9w+ n km from some planet's center, the acceleration of gravityn w9n98jva+ vn is $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 qtyjw if2/vm.bzyyr e1tj;1 -4t1jj,N on the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is irjzjyijeb-1j .1 1 fywv2 /ty,;qtt4mts weight?

  By how many newtons does the weight of a 100-kg person ch *jcy-udn52ys*k-(i8rc e rr tange when he goes from sea level to an altitude of 500nrtid*8ru-kcsc *( y-jy 5e2r0 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point ql(hf3frvlc1g; 53lwr. cs;m 3r above the Earth's l q3r ;v5( fcw;mfcl1rs3 .hlgsurface. What is the satellite's weight?

  A spherically symmetric planet has four tim:. udb zubn byc*jf+w(33wt3 qes the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much wofw*jw qub3y bd z3 .3t+ub(nc:uld it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and S)ep+9 a i3k60yzxd qicun all lie on the same line, with the Eaiep kx0yiaq +3c)6 z9drth between the Moon and the 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 tra+ a*a9yhe3rj snsported to 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 vdfc5(p;va77k -sebklow circular orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed5 csabk;(7pdvv 7e f-k of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbime*g4y lp ad8jl(2uh+ - lcr2xt about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean r 2d-x*lpj( yregu2 l8+4cl ahmadius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km abovef khf3q v4f/ sq*;nqy. the surface of the Earth. It is observed to have a period of 89 minq /q43.fvy *fqhkn;sf. What is the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter(fuj9eh4 h e,+0 +l1ddojxtlr 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 ra( lv4 qpqx1 +)ja acx+lmv*kq0dius 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 has or ( jqfaf-8nbd/.n ypz,)jwy5rbital radius r, and(qn a8)f/p dj.zybfy5 r-n ,wj moon 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 im si)5ew(a jl/s $7.78 \times 10^{11} \; m$ 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 Jupiter 12 years t4)+ vhb j3hzfaf3vv8yhh,q( :k7x dm do orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Ear d vhhmf,j 3fvkvzay : h4x(h8)3q7bd+th to the Sun is $1.5 \times 10^{11} \; m$.)