Is it possible for an object moving with a constant spumjz+ ixg9+ k4eed to accelerate? Explainmzuxk4+ 9+ jgi.

  Consider a particle moving with constant j5jw1 zx:xzw,4zni q+speed such that its acceleration of constant magnitude is always perpendicular to its velo,5zz4 j1wx:j+wzin qxcity.

  An object moves in a circular path at a c*vni*:gfp9luk48sem2bsm u k5 er3 5m onstant speed. Compare the direction of the objectrmnlsf3k*ik 45u 5s:p*eub298 gm emv's velocity and acceleration vectors.

  When an object experie)i;:ixl.3 nnrmyv1wq/7wb d v nces uniform circular motion, the direction of the acceley/nxqdwv1vri lbn w.i:) 3;7 mration is

  Consider a particle mov;f6 p9usa)o; 0y8rxwz qs c8cding with constant speed such that its acceleration of constant magnitude is fc9 owc88y6;;xqzs paru 0 ds)always perpendicular to its velocity.

  What type of acceleration does an object mov/di/mfv8t; (:ujgky1 o6 zbi aing with constant speed in a circular p/j8ib:umz tda6 fv/i ;y og(1kath experience?

  What force is neededbrthlh9nts v+1t9 /tz(00 sox to make an object move in a circle?

  When an object experiences uniform circular motion, the direction of thee9w td/(: ju8iy ;5cjhz2 a-w7ryxet6t mrti. net forwa xud9 jyy;(2i8 j/.w re5cttthz7: m et-ir6ce is

  A roller coaster car is4 h;swc l f1uqk0w4n;a 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 the loop, what is the minimum value for its centripe0nk;u w1wf 4s;q4 hlcatal acceleration at this point?

  A roller coaster car (mass = M) is on a track that8tfi opz.r,iqra 9 e:dj ;z:ww5*e5do 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 tqfezo*owei5 dtj:wrpzr9 d.:;i ,a8 5he loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a setk;q +8foa 3fnmi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on him in8to af+ qkf;3s

  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 radius fgij +3j5veu.b 6:x pq$r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of rad ; 9pycr,gac4)t6i spwius r at a constant speed v. Then it goes around th4a6p pit9s)gr,c;w cye 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 time?

  A car goes around a curve of 3;)dk/zzh:ih u5yaks radius r at a constant 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 aroundu yizsd3k/)a :hz;hk5 the second curve, compared to the first?

  A car of mass m goes around a banh+ljz,l ebs24h) s s/eked curve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the ho2l)es 4/sjs b,+h ehlzrizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves onzzepf7y6s o7v08 2j0 rrc.9vgvyy ti. a bobsled run 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.07 .rypv vez2zjc8yvo 0t g9s i6rf7y larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant, buk4nom(wuz u) 4t increases upward from 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 4 w)(4uznkmuo do this?

  Is it possible for an object moving around a circular path to hal3s+;7y11rbgkjy -fcqa 0c 9sekpq) ive both centripetal and tangential accel kqgb-fija09 sqplery)371+1 ;yc c kseration?

  The gravitational force betwem e)l . ep2j,(wmqm4nuen two objects is proportional to

  The gravitational force between two sbgw f:( s; tr85xlc7czwf c:f i4gk19objects is inversely proportional to

  Two objects attract each other gravitationally. If the distance betwee rwtje4 mq/;l /fc+ymg.dph)5 wkz**kn their centers is cut in half, the gravitationd4wtm 5h+zkgcj/.wyrkp m);e/ f* *lqal force

  Two objects, with mass wtlbx98 *e k,vm,gr;xes $m_{1}$ 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 masseqw:sc d i.mwyii:g,8sf.hr57s $m_{1}$ 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 g q+5g4 1yagidq(jnx* wravitation.

  Compared to its mass on thua :to+re1z0 fd:6a mp bcvj;.e Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixtx.4s a w*4tad d-arjo;h what it is on Earth. An object of massarad d;tj4.*x4o-wa s
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's wei2;3ra7p, fsa fk yyhppd418apght

  A spaceship is traveling to the Moon. At whatg7/*wz a qkf3y point is it beyond the pull of Earth's gravi/yzk ag*7 wf3qty?

  Suppose a satellite were orbiting the Earth just above the surface. What i/j gjxncn tl,jg;c2u 5l 5ao,4s its cj lc,t ggu4 55/x ;j,ljcn2onaentripetal acceleration?

  A hypothetical planet h17 cjth n6xo2u qt+at5as a mass of 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, th7t jc5utxh q+n6t1ao2e acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. The1dkk*v8stcs9i* xi8:yjpq ;o radius of the Moon is one-fourth that of the Earth. What is9:i pty 1okvcs*;di8 jxks *q8 the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice thes):zo;tktp:8 exa 2 un radius of planeto tt;ae :s 2uz8:k)xpn A. If planet A has mass m, what is the mass of planet B?

  Two planets have the samekx/sw;c 8yukzh33,v *h h vkj2 surface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of pl w 3hvhjvz;*8uk3k2skcx /yh,anet B?

  Consider a small satellite mov; llr)1xqi:sc ing in a circular orbit (radius r) about a spherical planet (mass M). Which ells q:i)c;xr1xpression gives this satellite's orbital velocity?

  Satellite A has twic 7wka1alyu wx9n;znkhq9/ (/ee the mass of satellite B, and rotates in the same orbit. Ckzn/19hlau7 aqyekn;w x/9w( ompare the two satellite's speeds.

  A person is standing on a scale in an elevator acceleratg/n.lwi(c:,h detxv: ing downward. Compare the reading on the scale to the person':ix c.t:nv (, whed/gls true weight.

  Who was the first person to reali3i c*3tavt10z7fir6zw t c h,pze that the planets move in elliptical paths aroutr6ft,h c1tivwic03 pz37z *and the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit aroun:3uo8 rh12 ady, sxhesd the Suns3 x:yhr,h82e au1o ds,

  Let the average orbital radius of a pvw5ct + n)t +6eth3pg fn,a*pklanet be R. Let the orbital period be T. What quantity is constant for all planets orbiting the Suv,nw )aptk+ t +hpe *gcn635tfn?

  A planet is discovered to orbit arofl1v o n975evtund 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, compared to the Earth's orbital pev59oelv 7ft n1riod?

  The average distance from the Ear4a l/t)qg xk+iu4yfbmg(-0p hth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third oha+fy)u-m4 t4/gxlp bq gk 0i(f a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.2:-un sbolfbt88x+oa *s5:d u9c tqzz

  List the four fundamental forces in nat6v)l pqd)e4g vure.

  An object moves with a constant speed of 30 m/9mr f yvvz1s hme1/53ws on a circular track of radius 150 m. What is msrhmv1z3f1y e vw9/5 the acceleration of the object?

  The maximum speed around a level cu0n sdiv m1i(y9b4xmue c+mb: 5rve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factom (1m94ims b+0e:byvnu i5xcdrs remain unchanged.)

  What is the centripetal acceleration of a point on the perimet7ue.7dihzcm.f 3t, q hhbq+ x8er of a bicycle wheel of diameter 70 cm when the bike is moucmh 7h. fx+ 3hb8idq7eq.z,tving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m fr5i pj rc wi+;3,gxd6ktom the axis. What is the centriii3w, k x5c +gptd6j;rpetal acceleration?

  How many revolutions per minute must a circular, rotating sendhl+fok 8mt5;gl);/bz6 enpace station of radius 1000 m rotate to produce an artificial gravity ofetz/8nm hed65+n); k;gblo lf $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. Itj,d8c-f i9t kr goes around a 13.7 m radius turn at 96.5 km/h. What is 9j-,fikd c8tr the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-tn 2k vigfn2ma7t*16z m string. The system is whirled in a horizmi2 2z7knfgv n6at* t1ontal 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 whirle4osec 2nk19ge d in 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 a2cn91geoeks4 t this point is given by

  A stone, of mass m, is attached to a strong stringg,uiby(5hc 4x and whirled in a vertical circle of radixi cbugy(5 ,4hus r. At the exact bottom of 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 acceleration of 4g when pulling ;evt ;gf.d(f:yabs -y out of the dive. What is th; ;ty:(sfgb-f. vyda ee radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (inngyi4zfv *5jtt obn9y4 2 asa+36t ,nw which the 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 his normal weight. Hotjyf g+4 4 avy29anbonin, t*s z3w65tw fast is he going?

  The maximum force a pilot can stand is about seven t1nvs+8b09 gwi)yv kkp-h wk,kimes his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dikibv9nk-w k w)s+ h,k10 pvyg8ve, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius8k e1cd9 2zpza horizontal curve 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 frictiozpza9c1e 2d8kn between the car's tires and each road surface.)

  A car is negotiating a flat curve of6-n ov406u .fnke, swi6bj qbh radius 50 m with a speed of 20 m/s. The centripetal force provided by fricbvqos4h iek.f ,w-6unj 66 n0btion 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/phxkt+n9; hvjd : 3-)sw xwxs at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car n s+kjhs p;xx )t3wxdh/v-w:9 to make the turn?

  A car is moving with a const+2 3i yxvo/abfant speed v around a level curve. The coefficient of friction between the ti2oivy b+x3/af res and the road is 0.40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsl xm*h/ugh+,h 8jt*zjcl lhd3:ed to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictionhxu+gl tj8 *3h*zlcdmh j:h,/.)

  A horizontal curve on a bobsled run is banked6e 2jbyqk sjy0+bth-f6mzn: +:zp oe+ 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 mpnn5i )v c/sgw8vd::lm03m hv q82ed100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked a86 zsxk4wj,0m 7.yuvso xi:dqt $45^{\circ}$. 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 rbu/j)5w 9ykdg sz7od,evolving uniformly in a horizontal circle of radius 0.50b gw5dyd,so7 9/zjk )u0
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 accelerdixr-w w8- ;km9z z4iiates at a uniform rate to a speed of 45 m/s in 15 s, moving on a cmi k8d9w-r;- zix4wizircular 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 (4xswavfj33r-u +t w 7vlstz: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 gravitatio5bxzpqy4 0f-i7n my*d;gmbr* nal force on a 70-kg person standing on the Earth, due to the Moon? The mas;gd *z0mibfy7 *5xn4mbqy rp-s 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 between two masses is F. If thermkbve+ 7 eg39 masses are moved to half of t9r37eg + vekbmheir initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Evf9wh3vh4 z *u; 7wv kkt2bks0r ua2b7arth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth bt r7fh;hwvuk*b7k09wzs2u a 3kv2 4vcancel?
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 0n(wf8sgynijtu2(45j tpwb8 f(/f gr$7.4 \times 10^{22} \; kg$ 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" ats31s3e4/bcq o jhni)y om)v7s a distance above the Earth equal to the radius of the Earth. What is her acceleration due ns 3scq yv7 4m1jsiho /b)eo3)to gravity?

  The radius of the Earth is R. At whacy x+spnw1 ;j (wa9tf;t distance above the Earth's surface will the accelert wxj;fwc;+ a9y1psn (ation of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its 3it0xbxb-4t.f uc.us surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceler .uxu.bt t03 xcsib-4fation of gravity on the surface of Mars, is

  At a distance of 14000 km from some platb6. 5a +ryyxdwgx 0g6net's center, the acceleration of gravity ibyr5a wgd6tx+ 6.0yxgs $32 \; m/s^2$. 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 radiu j yz1wniitfc,+r/hs5 .5nm/ihy6 e -bs r. If the object is raised to a height of 3r above the Earth's surface, what is its weinhsjimrc ye-1+/ihn zbf iy ,5.w /65tght?

  By how many newtons does the weight of a 100-kgh d4j.ksv-hi 9jdsj;q wp65q- person change when he goes from sea level to an altdv 5k9jj d4 jwq -qpissh-6;.hitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite ork :w 3e4fh5vpf mass 100 kg is at a point 3r above the Ear e5p3wh:fr4 vkth's surface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice itw; zg;c f0xoi cvic.5e8wmd1gd1p- / ts radius. If a jar of peanut butter weighs 12 N on the surface of the Earth,/ p8cg1i.dg owz-1;wc5vdeif0 ;cxmt how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all li1fh2vbhpbs(wq +ie*f6g3 4ije on the same line, with the Earth between the Moon and the sw +2bh43 vhi(g6*jfe i1pqfb 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 txzgi1:jnf ed9.gx ,)wo 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 (zsiqu 7kp6c4 2i.e., it just skims the surface of the Earth). What is the speed of the satellite? (Th6z2ipqs 4k7 uce 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., it jub:nnc go c5 azp*d5:(xjv9 e7ist skims the surface of the Earth). How long does it take to make one revolution around the Earth? acovepdx b7 n:5 9z5ic:*j (gn(The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above xg3.q1n. yjw e ,jh u,25i .syiakbt*tthe surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The2, ht.k *j, yiitbyg1 qe .a3nxu.5jws mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbiv-cukj 2v*- eqtal 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 ry0,y*clo g; nz: vr3ihadius 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 orbital radiuwr9n9:pp+ j lts r, and moon B has orbitt+:9p 9rp jlwnal 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 is vmee1z2);3pc6 zyx zd$7.78 \times 10^{11} \; m$ 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 Sun once. What is toj:s8m (vkk 7whe average distance from Jupiter to the Sun? (The distance from the Earth to th(sjw7omk: k8 ve Sun is $1.5 \times 10^{11} \; m$.)