Is it possible for an object moving with a constant speed to accelerate? Exo n2m3yhc q*w c1yrgx3 7b//ytplain.3hr c1*n/c yw7 tqbo23yx /ymg

  Consider a particle movin;snl+ lg4nn;e3c: xjvrw u e:0g with constant speed such that its acceleration of constant magnitude is always s;uex3n;wn0 cv4lgnjl+: er:perpendicular to its velocity.

  An object moves in a circula: 9/y g0qlvjwer path at a constant speed. Compare the direction of the object's velocity and accelerq:yjew l0g /v9ation vectors.

  When an object experiences uniforll:o5li np (m*m circular motion, the direction of the accelerat5ni: (l lmo*plion is

  Consider a particle moving with constant speed such that its amxgcd*nwz+9-c+ p0v t* )onul cceleration of constant magnitude is always perpendicdp)tnv * z9xccou*+mlgw0n +-ular to its velocity.

  What type of acceleration does2w2: jv m +fzo3(lahqn an object moving with constant speed in a circular path ex q2+zfa j2o vl3:nh(mwperience?

  What force is needed to make an object move in a circl0bq:th, nl t1r.wbfo4 e?

  When an object experiences uniform circular6-hbwdhpxp4 6 rl)i,u motion, the direction of the net forc ,x )-b upwphh6id4rl6e is

  A roller coaster car is on a track that )qcy.9vqf, 73)mppfy bwdeb6c 6-t tgforms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value for its centripetal accelerativ-fyt.b7e3 p m 9)pc6qybtfdqw, c6)gon at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (radid*lleu/22ah /uj v6xn us = r) in the vertical plane. If the car is to just mainhu *6 u l2dj2ae/lxv/ntain 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 vertical dive then follows a semi-circular u7sf111bqv so arc until it is going straight up. Just as the plane is at its lowest point, the fo1 vubqfso171srce 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 ci/;;ej nrl/k nurve of radius $r$ 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 speed v. Then it goes arouq 2hfe*8 tklzku 50z8pnd the same curve at half of the original speed. What is the centripeta5 f8z82he*qlkpz0 ku tl 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 * )kqwo vc k1v:aw,+eoa constant speed v. Then it goes around a curve of radius 2r at speed 2v. What iseok vw+1),w*acvoqk: 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 d04zv6 lve1yxtj,6 i:b iffx 0v. If the road is frictionless due to ice, the car can still negotiai:0j6 xvfl0f,tdv6 z1xbiey4te the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, buz0:*f1dl) g z9jpm hiit one has twice the radius of the other. The safe speed (no friction needdi z)zlp9f1*i0 mhjg :ed 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 bobsled track is not constant, /;7.dnl c9p* fdnhcb fbut increases upward from the horizontcn9bf7dc;fd p l /*nh.al. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an fag*-r d31le5)x d7ukp4mqcc object moving around a circular path to have both centripetal and tangentd14-7q )dc5p*l fkg 3aumcrex ial acceleration?

  The gravitational foruad (f0o3u gqiikn-6gnpc2)q2oo. t, ce between two objects is proportional to

  The gravitational force between two objects is invj(*5bjmsd+5ag*a fkp48wh le ersely proportional to

  Two objects attract each other gravitationally. If the uuzanl0db 8dxz.5* 1wdistance between their centers is cut in halz0d .z*8 d5 xanubl1wuf, the gravitational force

  Two objects, with maqy5; pdsl l5k(rt4zs( sses $m_{1}$ 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 masses q+am+1dy +mqs $m_{1}$ 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 universabf32t);sc o6uro9 ro* *o9;jo* kywpw2 semgvl gravitation.

  Compared to its mass on the Earth, the massu7c7qr x.1tg,5k8 olz/cbj wx of an object on the Moon is

  The acceleration of gravity on the+a0z -(a48rnvngh0eifz lk ff1vn5 :a Moon is one-sixth what it is on Earth. An object ezvnr1fn8-af havki 0z4a:gln + f5( 0of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket'cyh or- ,j.lh+s weight

  A spaceship is traveling to the Moon. At what point is it beyond tms-b)ex blk,4 he pull of Ear) m4bl,-eb ksxth's gravity?

  Suppose a satellite were orz750cmxf xj:t biting the Earth just above the surface. What is its centripetal 5 m:ftx 0cz7xjacceleration?

  A hypothetical planet has a mass of half that of the Earth andd:i*q6 un m)zgb9+ hpaab h5-a a radius of twice that of the Earth. What is the acce5 ) u96: qmbah p+hband*gzi-aleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on h zbvwikng./d 0v x.+1the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that o.d+01wnvz i.hbkvx/ g f the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but plami y,(-zl(rtnnet B has twice the radius of planet A.mzry(-( iln,t If planet A has mass m, what is the mass of planet B?

  Two planets have the same survmpsa*y0 /ge. face gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radiu y*gps/avm.e0s of planet B?

  Consider a small satellite moving in a circular orbit (5zmip9 t/g)zfa olka*m aou 1e4c3ivk42mq8 9 radius r) about a spherical planet (mass M). t1ziqkz)a cak*g9m/5a39u2 ploeo mf 84iv m4Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass o s cp jkth92uzkl,+n0psg-u:-f satellite B, and rotates in the same orbit. Compare the two satellitguh tjsps,+ k-c90:- nzk2pu le's speeds.

  A person is standing on a scale iu)7cdqkp,eub x s8 a g7n,gxdk-/-1ban an elevator accelerating downward. Compare the reading on d87q7g,x/xg ku - a,s-n1abb u)edpkcthe scale to the person's true weight.

  Who was the first person to realize that the planets movt k0k q gps7dtx*.6qu:e in elliptical paths arptqd g. x0ksku6tq*: 7ound the Sun?

  The speed of Halley's Comet, while traveling in p5d;/pj xbqe -its elliptical orbit around the Sun,be/ 5qxpp;- dj

  Let the average orbital radius of a plane3/ jl m.acst1*hr9f4rxgwx 2zsd7o,k t be R. Let the orbital period be T. What quantity is constant for all planets .r9431aolw2jsd*7trhk/z xs g, f cxmorbiting the Sun?

  A planet is discovered to orbip i;e0ex :goone75 xd*1u iepsh(-c8o t around a star in the galaxy Andromeda, with the same orbit *oecnu 57ip sxehd-(:o 10e;8iogepxal 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 Earth's orbital period?

  The average distance from the Earth +y.dp+1ta*1v(h kqyze lxn 2r cv*flsk e;.o(to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-thik kvl d+yhrv y 1nels(2oap;e1 z.q *+tx.(f*crd of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.)7h96k:4nb++h z;um zwtp q uq9vmnwd

  List the four fundamental forces in natj;e dzsf)0) hmure.

  An object moves with a constant s mdv-9 84tbwwjn/*uo kd c75vrpeed of 30 m/s on a circular track of radius 150 m. What is the accrot5u/wd4 - v c*bkv ndw9m78jeleration of the object?

  The maximum speed around a level curve is 30. :h-a8lpd, bw 7qvpud:g 6cia80 km/h. What is the maximum speed around a curve with twice the radius? (Assume all ovgq8-lidb wp7u,8c6 d:ahpa:ther factors remain unchanged.)

  What is the centripetal accelerationy,m 3k,fda 7oj of a point on the perimeter of a bicycle wheel kdfm y3oj,7,a of diameter 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. Wp 8+v s1gjqji1 6vadd.ujjr1k,o7(hihakp hi7(jao jg8d+v.j1qv d 1ir 1suj,6t is the centripetal acceleration?

  How many revolutions per minute must az(zksq/2foga / ssg5/tq 7j 2n circular, rotating space station of radius 1000 m rotate to produjkznga2q/7 s 5z/qs(osf2 /tgce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass g k:cd: nhhdsv1i:;5j 8knd, aof 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centrn 5:h nad :ddghv8,i kj:sc;k1ipetal force on the motorcycle?

  A 0.50-kg mass is attached tov d+hv5dgodth,*)/a v the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximov, d*)ah dv5htvgd/+um speed of the mass if the string is not to break?

  A stone, of mass m, is attachk 9bxor5(ju. ced to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is j(.cx u5brk9o3 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 vmn rq6+0.n7qo z+l lrvertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's wei0mqo z rn+lv.q6lnr+7ght. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleratis;80vj u6w-xc-b mor ion of 4g when pulling out of the dive. What is the radius of curvatu;wvxrjm cisu- 6ob80-re of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which thejn*je j1pw+z1 center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat with only one-half of hi1jj1w *zep j+ns normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times his bse4e bb3gy*7 weight. What is the minimes7bey* 3g4 bbum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 81vj: a.m5vdhro mze8i3 y+w :b0-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round avm+e5hy8j3i: a bmd :o1v .wrz 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 cur6, pk7kba vdqxllk a92+ x(u-hve of radius 50 m with a speed of 20 m/s. The centavkb2halu6+xd- , ( 9 xqklp7kripetal force provided by friction 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 at a:w ng-y )zg7bt speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to g:yw)- g7ntz bmake the turn?

  A car is moving with a constantbxc ))(ugw g4i speed v around a 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)gc)wx(i 4gub car is to stay on the road?

  What minimum banking angle is required for an Olympic )kyjfv :i6nkagy/ 7w9km az74bobsled to negotiate a 100-m radius turn aa7kg4 fkj6kvm7: yn/ waziy9) t 35 m/s without skidding? (Ignore friction.)

  A horizontal curve onyz tq bneobk, 029 e-;+hr6yzl a bobsled run is banked 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 atfc r53i u85stk xvhn32 an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked .vouadn8fjg-s sq9/c )n+b;gat $45^{\circ}$. 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 is2 ier+z(;mb4 fkoa t.v revolving uniformly in a horizontal circle of otav.i 4bf e 2+rk;(mzradius 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 cbsqmr9q hocd, oak206)76y yyar accelerates at a uniform rate to a speed of 45 m/sdy7so,ka6 c qob0 hr)96y2qym in 15 s, moving 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 consists of a proton ofp.vf x)u5g *wa 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 on the Eaat0x :rbjw*gh;mmmo+6 r2-q f rth, due to the Moon? The mass of the Moon is wx+;ojmgm*2r q- 6a:tf h0 rmb$7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masses is F. If the massesijv/m5,i9, 1faxxy mw are moved to half of their initial dist 9yxm,5f1mawj v,i/ xiance, what is the gravitational attractive force?

  For a spacecraft going frosvk8 q rc , (vodh3sw9*sox)7mm the Earth toward the Sun, at what distance from the Earth will the gravitational forces dudovqcw 8v 3k(x or)smss *79h,e 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 ifawvts(y e :n7,5e 9rxs $7.4 \times 10^{22} \; kg$ 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 distancpqdn;:*sh; q/ozj 3ppj3ij 2se above the Earth equal to the radius ;qzqp h:jjssppj3d3n 2 *o;/i of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At whbp 1fgo-y1gbh+ 7vbv-ao-+p ;enk* l5 htcy5 vat distance above the Earth's surface will thgt*y7+l 5p-hh1vafck1; bo b pbo+v- nevy5g-e acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times theb qr/sar8wz 0n m:o6cgg4,sb,uq k;+ s radiub;8/,g cszsqb4a6qg:o r mnuks r+0 w,s of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from sonxteq j7 q-c,(6 qd. eo1y-hv poyr/b,me planet's center, the acceleration of gravity is eqjo/7tdyb cq.rq ( ,o,p-nh v-y1e6x $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surface of the Earth. d kpf8w fv7q 5/q.1xio The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, whaf8i1wpvf .dk/ q7q5oxt is its weight?

  By how many newtons does the weight of a 100-kg person crb ot :c((vm;i w((gaz 7rc5cchange when he goes from b;(ctr z5 aci(wc(v7r:mocg(sea level to an altitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radiuscp:akm+ t x2 kryau oa+2lxn kt*)h(do**0v4o r. A satellite of mass 100 kg is at a point 3r above the Earth's surfl* a+(0:uacoo*pt+nyx2*42kotmh k ) vdxkarace. What is the satellite's weight?

  A spherically symmetric planet qiw z:co+ttt)fgsr6 ( 2xo 4.mhas four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, xc+oi )w:tqtgt(42 mzs or6.fhow much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same l)rlwb0h+( xzi+g 4n ec sgsz:-ine, with thehb++cew( 4-gs )g :zlxi0sznr Earth 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 i pqz/sz1o 473twl p4lhs transported 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 low cif/+ls tia1so ,rcular orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of the +fl s,/ta1osiEarth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e*6qfe6 nucw g6., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mea66qwfg enc u6*n radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earth. lz).au 9cg)p v It is observed to have a period .gl)9za up )cvof 89 min. 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 hz og)t7wu cl2s zg601orbital 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 02gm,r )i1eh- ;mra lms5pwfgwith a radius 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 c ;u wwd-p8sia(ircular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. M(iw; sd8au -pwoon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter isf mxjx94e+84su6vm m(jobp,c $7.78 \times 10^{11} \; m$ 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 to orbit the Suhx*b8c 8hals3n once. What is the average distance from Jupiter to the Sun? (The h8ahlb 3 c8xs*distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)