Is it possible for an object moving with a constant spr+8rm 2kmy(vz6shsn ;eed to accelerate? Explain+k6yzv(r 8ms 2nhms ;r.

  Consider a particle moving with constat+b w-tv -m9 6mnc8fvfnt speed such that its acceleration of constant magnitude is always perpendicular t tb8f t-9cmnwv6-fv+mo its velocity.

  An object moves in a circular path at a constant ry o4+ob+ivv aw6w+ f2speed. Compare the direction of the object's velocityv+ a w4y++oibo6wv 2fr and acceleration vectors.

  When an object experiences uniform circular motion, the directi ss7l)yc:b7kj0 rihl3on of the acceleratio3rj)0cll h7bk si7y :sn is

  Consider a particle moving with constant speed sucum:agg:sn j;r:4y. xp h that its acceleration of constant magnitude is always perpendicular to itsxg:jpsay4m : ur; :.ng velocity.

  What type of acceleration does an objq3 oasc7,hoz5 w:*s toect moving with constant speed in a circular path exper*awzsc,qt735ooo:h s ience?

  What force is needed to make an obya (u8qiphmj7kq6txe r2j*wi2e3q 70ject move in a circle?

  When an object experien fq pt+7kjv zyiw2**-hces uniform circular motion, the direction of the net for+27 *yjz fi*pwvtq- khce is

  A roller coaster car sjsy5 vu-5c k5k-veszl/u1k0is on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of tk0k-/ v s5-1cyu z5usvs ejk5lhe loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track tha nrymssat-qa5*:y/: fvl, je.t forms 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 the mq::r snv*ej. -fty,/ls ma5 yainimum value for its speed at that point?

  A pilot executes a vertical dive then follo1 thd2ri:e ,baws a semi-circular arc until it is going straight up. Just as the plane is aibd ,h :r21etat its lowest 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 c:lszq,g9i 8opurve 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 radiusg-3- l6 /u)2 owdnfoxejqndd 2gj, xd3 r at a constant speed v. Then it goes around the same cu)dnxdljg dx /ef w uo62-g33dq2-o j,nrve 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 time?

  A car goes around a curve of radius r at a constant spf(4,.dizxygt j*mxq2eed v. Then it goes around a curd2.xigmqxj ,*4f (zt yve of radius 2r at 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 am,sf q* lzs3h e;50som banked curve of radius r with speed v. If the road is fr emz sq0*3o 5ss;,hmflictionless due to ice, the car can still negotiate 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 ra6g1k+ 9ffce(n+ n uzvuvujt i2 /vk/;un are banked at the same angle, but one has 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 on the larger radzk(e29 v at/gu+v vfiunf1 c+6u; nj/kius curve?

  The banking angle in a turn on k ie3kt/ *l g);.hnds1lk/wg55u hwbm9) teazthe Olympic bobsled track is not constant, but increases upward frtg.kb ashd kk; he1/ tez*3) lugw n5/)mlw59iom the horizontal. 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 object moving around a circular path )fxp)dw fobga ;1.)el4+ vcurto have both centripetal andfdbf +;.4))apvc)lr1 g woeux tangential acceleration?

  The gravitational force between two objects is proportiop pq-k)(n4 5 coxthmw7nal to

  The gravitational force between two objects1oq3muh g x5alug/ ochx 82*s. is inversely proportional to

  Two objects attract each other gravitationally. If the distg m1emlfmps)4o(ss - 0ance between their centers is cut in half, the gravitational oesgm(l msf4ms1)-p 0force

  Two objects, with mah/hb/pli/ ygp d2zl6 1sses $m_{1}$ 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 ma 7v(rd -wntei:,2jk+dcpd. bksses $m_{1}$ 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 universal gravitaoxh5c*+ih 1 fdtion.

  Compared to its mass on the Earth, the mass of an object on the Moou0z5s372n rtimp7e v en is

  The acceleration of gravity on the Moon is one-sixth what it is on-j7 tkgf6sfqy7 .ib/frrr))q j4u)k v Earth. An object of mryq.)b qv)4fu t f-jkf7 sk)r7/grj6i ass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the 5qy vuu-4l2:i tg sl (oc(q;aurocket's weight

  A spaceship is traveling to the Moon. At d js;cs+ky 4xx5jo89owhat point is it beyond the pull of Earth's g8j j4 5;xxsoydc ks+9oravity?

  Suppose a satellite were orbiting the Earth just ao59,hpmvi9 dkhw1* dhm* x7 hs oe/ep(bove the surface. What is its centripe w ,h* 9m1hxp9deov*s k7p5omhi(/hedtal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radi95er+dv ue x(r4:idz872toq zqipq z 6us of twice that of the Earth. What is the acceleration due to gravity on the pxu9 de r+iqrq(zitvqeo7z5 p2dz84: 6 lanet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. tlfsv)z9iy ,)j5jha0j c-(na The radius of the Moon is one-fourth thaj)95atfcaj,) jzs l-0h ( vyint of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity,v6qu8sx4 d v4e but planet B has twice the radius of pl6dsuxv4e84qv anet A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but p2 m(-mm4y- ymrtcqu:g s4 tm f54,ddfvlanet B has twice the mass of planet A. Iffv2 yr --gtm5ytd f(: m4, mdq4cmus4m planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (hsj3ja6 lwrr, n-9sk;; tx( uxradius r) about a spherical pl r3;jh-s j;uawxk sxlr, 96n(tanet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, andn(0 g5vsir p8k rotates in the same orbit. Compare the two satellite's spee80r pksvgni5(ds.

  A person is standing on a scale in an elevator acceleratinl7k:d ch,hi (jn5;qerg downward. Compare the reading on the scale tnkje5q(,rh 7ih :lc;do the person's true weight.

  Who was the first person to realize that the planets move in elliptical paths x,3i 0zxfakj;qc/0v*ii dkx( around/d a;kiz0xk (c0*jxfx, q i3iv the Sun?

  The speed of Halley's Comet, while traveling in its elliptical o0g.*,h( dd2xcl5 zu fy qk,hoprbit around the Su oy0.5zhux,cdlqdkh f*2, g p(n,

  Let the average orbital radius of a planet be R. Let the orbitalp bz-ds/ :3dwlg7n *nwrhla:5 period be T. What quantity is const7ralnbwg :n/:zsl3d*w5-pdhant for all planets orbiting the Sun?

  A planet is discovered to orbit around.h02s waj e)gqi .rkilwbl6- . a star in the galaxy Andromeda, 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, compa0wr-ik2 a.bilsqjl) 6h..g w ered to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as one "astronp)i3) aqmu9hbuq1hl m-uri)n6-b ay/omical unit" (AU). An asteroid orbits the Sun i)-i )/9a u1m3)ba hynqr uqmulhb- 6pin one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.rv0vf1s.m vkk77h, pt

  List the four fundamental forces in nature9xbt(qo7: d jv.

  An object moves with a constant speed of 30 m/s on j ce00*p vl3sgze3te; a circular track of radius 150 m. What is the acceleration of tc; 3etlgjz0 *e3esv 0phe object?

  The maximum speed around a level curve is 30.0 km/h. cx2t n7sp xuhzt.5.dc3 k;-ubWhat is the maximum speed around a curve with twice the radius? (Assume all other factors remainn.7 p2u3dc bsxktzcu.x5t h-; unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle wh em(dfwrq170m eee m70w d1q(mrfl of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s iyn ;scbcm3n6s2je a kj74tn3: s located 0.200 m from the axis. What is the ce kn 2sj63bn:e47sam 3tnc;jcyntripetal acceleration?

  How many revolutions perhi3f q,kai; u2 minute must a circular, rotating space station of radius 1000 m rotate to produce ,ui2a 3hk;qfi an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of ;:gwhr-vyx :qi f7ka:250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motor ia:g:;xy:rhv wq7-kfcycle?

  A 0.50-kg mass is attached to the endbgpzv*4131j5t -vtimn v ap/u of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withsmv ai-jnbvttgz p34u15 /1v*p tand 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 j5vfehwi5 ,,hi, e mm4in a vertical 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 aem54 ihvj,5e ifh m,w,t this point is given by

  A stone, of mass m, is atta wfa:y- 9vz3h/*0kuo vorv(ejched to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tervzw :v- ou (3o evk/*yj0haf9nsion 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 acceleration of 4g when p( 1tk5to1v oy hufcn om-(wl40ulling out of the dive. What is the radius of curvature of the loop in which th04h5 vuc(t -11nofy otwolk(me plane is flying?

  A pilot makes an outside vertibt,.tsr gl*nv4u o(w+;yt *ej cal loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he iw*lj, 4(;bot*ynv tg .tr+u ses 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 xj-3v gvgtm1.r0rq 9w tpy1 p4about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can trxptp9j-v .140 gm q3t1gv rwyolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds og.pkyr -) +x.ccg/enan 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of rad. o/gn+p )x.rkc-yg ceius 320 m? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a f46l7juq mwx b3lat curve of radius 50 m with a speed of 20 m/s. The centripe xmq63 u7bwj4ltal 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 spee3 *7.yp) yhnqk enrua8d of 14 m/s. What must be the minimum nn7)qe* p8ru. ykh 3aycoefficient 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 a level curve. The coeffx(7spq.v05r jcumu7aicient of friction between the tires and the road is 0.40. What is thj(7 sm.apu7ur0v 5cq xe minimum radius of the curve if the car is to stay on the road?

  What minimum banking angl.g3 t1jutb+ gn.*dn(0d2ccxpnmj9cle is required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s. xpun+cjnmt ldj0(c1nc2tg93g.*d b without skidding? (Ignore friction.)

  A horizontal curve on a bobslen1j24jir,g f ad 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 at an anglehe+ay ln5so9( of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is-oio*b c(.x fzi;)lqn banked 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 string is revolu b6n 2jv( 6feomx(.yvving uniformly in a horizontal circle o 2 fy66n(x(. omubjvvef 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 car accele r5/mqo 6.8r4lv ackummd5aw1rates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius51k 5q /4c6m uroml8ad wam.vr 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 protfma p2nwu7. 7grb-jyj:xl4c+on 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 standb6s znqrn( *lh+;1hxvb awv,2ing on the Earth, due to the Moon? The mass of thw+n*,xbza b1 6(hv sr;qh 2nlve 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 between two masxt0p- 6urt .snses is F. If the masses are moved to half of their initial distance, what is the gravitational atu srxp. 6n0tt-tractive force?

  For a spacecraft going from the Earth toward the Sun, at wc.qo qh,f:c/t3m21um xtf tx q43zb;fhat distance from the Earth will the gravitational forces due to the Sun and th ,f 1ot3;ch 2 cqffbtqq/4xxu:mzmt3.e 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 ac rk/l-w la9e jv+m( ,dx*5fu$7.4 \times 10^{22} \; kg$ 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-wtcqc 26dqs3 g7alk" at a distance above the Earth equal to the radius of the Earth. What is her acceleration due tq67cqgcs 2d3 to gravity?

  The radius of the Earth is R. At what distanzkbva xog q5q s mbyv0b/-+t3b;;b7b2ce above the Earth's surface will the accelerationos/0m-b5 3bby2 ; v 7qbvba+b qxzk;tg of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfactrg(-2ece l 6:7px btq e92qtgclu7;fe equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared l2 (bpe7xg27l ;9g6 r utefeqq-:tctcto the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet2saun8h899 g+ ih gwtq's center, the acceleration of gravityiqtua29gsh9 +wn g8 h8 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 N on the surface of the Earth. The Earth has radinjld1mze)v,yi wy / c2/4c/ tmus r. If the object is raised to a height of 3r above the Earth's surface, what is its ci 4wz/n/cv/ytjl m)dy me2,1weight?

  By how many newtons does the weight of a 100-kg pw 1n*-ud1m7epf35o s2tqttuterson change when he goes from sea level to anw*oedtn fu 7spt1-5t3u m1t2q altitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radiusr)8yba4;lmsea 00lpk r. A satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satellite's 0psak 0emla4y)l;8 br weight?

  A spherically symmetric6epp3t ega l-bc 5kp7op8uo7u7l 7 9we planet has four times the Earth's mass and twice its radius. If a jar o7o7p-p7bk9ee lu8 lwp 5gta37 eo6 pcuf 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, l t y( (7jx1/xfsnph 5ns4xve(r3td6 athe Moon, Earth, and Sun all lie on the same line, with the Earth bee3na xyp61stl(rv f7sdxn4 /(xth (j5 tween 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 trans 2(rf,9usx)7td;v bvxtn4 rl fported 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 circular orbit about the Earth (i.e., it jusgzy0y-l8hmn0tv0 nx0 t skims the surface of the0n8ytlhzn0ygm0 - 0vx 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 lowt+c39 7k cu-igklz9 yzmp;j c 8ncw8c: circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revoluti 3 t pic 8w;:kl99ujk+cz7-mcnz8gyc con around the Earth? (The mean 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. qylwi5m c *)z5n+(tmg It is observed to have a period of 89 min. Whatmngwq*(5zyi) +clt 5m 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 diuuuqf x7pg2ag fi l8 7sf-.)y6ameter 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 pqzzs f6/j93vv12 opb planet with 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 circular orbits. Moon A h3 rd.s1xu, uy-u6tq)gwvi( f aas orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. ,uyu)3 xut- wsg d aq6irv1.f(How long does it take moon B to complete an orbit?

  The planet Jupiter is 4tz.+k,dkr 2z p/5asrcu hu.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 Jupiter 12 y 1tbu z, ;io2qtejjd8.ears to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth to tbu 2ej,1q.8d ti;jtozhe Sun is $1.5 \times 10^{11} \; m$.)