Is it possible for an object moving with a constant speed to acceleratenb/iokjsdwd-b-6a hm/ 6 h83ssz5* k fcuwx32? Explai6/ whz mn2osikb*db/33cas 6fxswh 5j8d--uk n.

  Consider a particle moving with constant+takh(gd0l 6q speed such that its acceleration of constant magnitude is always perpendicular to its velociag0k h+d 6(ltqty.

  An object moves in a circular path at a constant speed. Compare the q/f 1.lynwxb 3s u(9mgdirection of the object's velocity and accelerx/umwfl9gq sy1n b3 .(ation vectors.

  When an object experienib: ;;zu ca3 odz5ba8vces uniform circular motion, the direction of the acceleration iodu ;8b b;zzav:c3 5ais

  Consider a particle moving with constant speed such that g7pso dv+qx 2 i+/*mvaits acceleration of constant magnitu7qp s*+goav/i +dv2m xde is always perpendicular to its velocity.

  What type of acceleration does an object moving wit.x+it5 q(rib bh constant speed in a circular path experien+triib (5b x.qce?

  What force is needed to make an object move i9ui*k sdaucblx;6 0o ,n a circle?

  When an object experiences uniform circular motion, the direction ofz)azn x2f/ e0w the net force ewn /0)fxazz2 is

  A roller coaster car is on a track that,kgp+gnq;tok3g afk*7q7s 1n forms a circular loop in the vertical plane.a1o ;7gp3tg+ qn7,fkk*kns gq If 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 a circular loop (ral9kxjdf7x394 *evar* ecf ap +dius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of theprl9f97 ed+v3*fex 4jack a*x loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circ15* t cd3o3ixf h,lmcoular arc until it is going straight up. Just as the plane io*3 5h1o,itdlmc x3f cs at 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 curve of r0e9zcqjxtaa01 mx ) c7adius $r$ 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 3ypkjd hn3(n/ at a constant speed 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, c(n3n /yd hjp3kompared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it goes arou0jhsnb4jg6(c/e bnq* nd a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the0bqj(bcng /4hj* s6ne second curve, compared to the first?

  A car of mass m goes ar:,,68v5yfje u qwq cbfound a banked curve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal cw qeq6cu5f,:vb y,8jf omponent 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 samems 2wqbjc+9/80ur aro 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 larqsaor 08 rwb2/mucj+9ger radius curve?

  The banking angle in a turn on the Olympic bobslw);m1u.mv5 8orfkpxied track is not constant, but increases upward from the horizontal. Cour. i;fm8p5mko1x wv )ming 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 arlqtj vi bwj l-bp(nr;*66o;+g ound a circular path to have both centripetal and tangential accell6rnjt ;p v6-( qw+ibj;olb *geration?

  The gravitational force between two objects is propor(ayna+e h2qn5 tional to

  The gravitational force between two obj*ee8k pu3 ut1lwv lqk,-ex x4(ects is inversely proportional to

  Two objects attract each other gravig1p jnb*hk6q.9 wk czdbhaq d3778s8w6a o* wqtationally. If the distance between their centers is cut in half, t w 697wocb6k*ahq h7b pa g3sdqdq.wnk1 z8j*8he gravitational force

  Two objects, with massdsv-x6vsod 1g v zz1d- 3tt6jg,/vt4lvw1gq1es $m_{1}$ 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 masseaygec e 91iy06kfpft 6b g)9n,s $m_{1}$ 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 gra-s8pa evu3y8 ovitation.

  Compared to its mass on t-y):fc y-k1t m4beh+siqw3 l/cfrj8xhe Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth whath+y uuvm)9sh9 it is on Earth. An object ofu h)s9hy+9uvm mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the:9t /kt;d a xezo 5(t iecw)qr6xa.faoc1g)p2 Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the5y he5zk,5)jtc8 zqdj 1m*bd g pull of Earth's gravitm5q5c *be g1,hk8jdztjdz )5yy?

  Suppose a satellite were orbiting the Earth just above the surface. Whaaqhs:k6+ kb; k-x vthb;ao :;xt is its centripetal accelerations; b;-:xoa6b+h; va:hkqkxk t?

  A hypothetical planetwqdhn.if0m) * xy(fr3 has 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)f*w y dm0( 3f.xinrhq g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-y 0tx r6e2ca5uo956gx bu5 xzbsixth what it is on Earth. The radius of the Moon is a6gbru6uy x0xzt 59oe5xb5c2 one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B xout1m8)h96 j zy xc8(a*lfl nhas twice the radius of planet A. If planet A has mass m, what is the masszcanl x91m 8(6uyxj l*oh8f t) of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass of mrzl wbnol/5u, 6s3 ne ;kq7e,planet A. If planet A has radius r, what is the radius rel; w,7mk5q6noz/elun ,s3b of planet B?

  Consider a small satellite moving in a circular or 8c-zcryg9(anb*p yx,bit (radius r) about a spherical planet (mass M). Which expression gives9-nxzr *b(ac8yg ,c yp this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates zcwssej. .6md6p))u qin the same orbit. Compare the two s)6m..s pjuecqd6z)wsatellite's speeds.

  A person is standing on a scale in an elekx* zf f/:pw,lvator accelerating downward. Compare the reading on the scale to the person's true wfk :* xp/zfw,leight.

  Who was the first person to realize that the planets move in ellipt7p vfqj2kog k0d*r.s.- n7n qkical paths around the 027kg7o-qsp *f qdnkn kj.v.r Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around thmf :p;8 nq(r(bnlvgo 9e S( br: ( lg;pnqfmnvo98un,

  Let the average orbital radigm(itp6 /ei8*z 3wlfu us of a planet be R. Let the orbital period be T. What quantity is constant for all planets orbi(mil g/p t uzw*8fe3i6ting the Sun?

  A planet is discovered to orbit around a star ikm5r r/jz2dx.v4 5 icrz (r+cdn 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 peri.5 crm 52zv(xdzrirdk+jc 4/rod of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun01x/;b.9nkj yy msnw4o nvtro 2u,j +f is defined as one "astronomical unit" (AU). An asteroid orbit sy;no/y9w 1m4t xj2.+no kufbnr0 j,vs the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.i 42ta uadthugin-c:q4ww/7 .

  List the four fundame ;3o)j1udmqu : plle8:jrlug9 ntal forces in nature.

  An object moves with a cont4 ,s ,m h1u6:axp:cgnx0s irxstant speed of 30 m/s on a circular track of radius 150 m. What is the accelerationhm4tcu,s ap:xsi x 6r1x0n,:g of the object?

  The maximum speed ary- uzd+c9c7 czound a level curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factor- 7y zcduc9+czs remain unchanged.)

  What is the centripeta6rl pkqrp /v .be08m9xl acceleration of a point on the perimeter of a bicycle wheel of diameter 70 ce8pv.6 r/rl0mbqk9 xpm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 kk 1p1 ( huiq0q.zdj;frev/s is located 0.200 m from the axis. What is the centripetal acc. (pqk ;k0fihqdj z1u1eleration?

  How many revolutions per minute must a circular, rotating space station of roh 0yu:gc c) 6z1bbbocg7 v2/badius 1000 m rotate to produbb0bb go/co6 ch1 uz7)cv:2 gyce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 pv.uuwb.5x s cu f.89lm radius turn at 96.5 km/h. Whatf u.b5u9clwv .u 8.pxs is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The sys 0id.wq+:lbdrtem is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed of the mass b.ri:0dd+q lwif the string is not to break?

  A stone, of mass m, is attachev6oj i6- m1-kfxb rum2d to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in ti1xv j2f6-r-6k u mobmhe 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 ci7bw av,2(0:0 wf)x2 sal ddanda vaqb.rcle of radius 2fd ).0:s v,axb aa2(a0lqa wnw7ddbv 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 experie -lll.z 6bmqz,2rii. jnces an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flyiiq6l. 2j ll.b,zrimz- ng?

  A pilot makes an outside vertical loop (in which the center ofcg8+ umb vue,; the loop is beneathu;gu8+,vcm b e 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. How fast is he going?

  The maximum force a pilot can stand is about seven times his weight. What ishkie(h ym5hrz.l 03scd( 8bb/ the minimum radius of ccd5 (rlbs3zk8 /0hmy.hhe(i burvature 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 80-m radius horizo pl )b.*btx:zjx4av -nntal curve with the tires on the verge of slipping. How fast :t -bva*j xn.lp)x4bz 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 fly 5z 7akb7khl )wn,:ijq 4kiz odhk47m2e)cs: at curve of radius 50 m with a speed of 20 m/s. The centripetal force prov5zka kdocie7kk z7nsqm 4byil ):hhw),472 :jided 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 speed of)z n1,dds8 c ct7tt.jz 14 m/s. What must be the mi)t s71dc ,. zc8ztnjdtnimum coefficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a con w4ez ( y2t0)nz5uynftstant speed v around a level curve. The coefficient of friction bt5 )(f0uetyy z42 wnnzetween the tires 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 bobsled to neglwm ;5w,g vi jzema07*2zulu) otiate a 100-m radius turn at 35 m/s without skidding? (Ignuz m5v)ul 7,a; wwej gm0l*zi2ore friction.)

  A horizontal curve on a bobsle oxul7n95q:g od 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 10dhl7 e9bv rvu991m0zk0 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankedygl0,i *j 3+cmbv s*( jbh+sv+k4kkwt 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 revolving uniformly infmfhzw +-6cs*abcr* (1 v1rwe a horizontal circle oc1r6 w+ aw(fb*smrvhce1 *-zff 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 3ddrmp r.e0 sqw/x *9pthe pit area, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical value in the b wmdr9/.d 3qpe0x* prslanks)
(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 fo//wqt r8onstna:8w fo81 c070 vrnzproton 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 pv)vx ;-yc (8df nir4xuerson standing on the Earth, due to the Moon? The mass of the Moon i4rvxy d(n uf)cxi 8;v-s $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force 6f7u n a30zjsvbetween two masses is F. If the masses are moved to half o3zva f6 snu0j7f their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Eaf2yk27x1ev( q .ghnnu rth toward the Sun, at what distance from the Earth will the gravitati qe 7k2n(n.vf 2g1xhyuonal forces 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 is0ux:l.l ki3ax7wsj 9ed4e bxgz2( k2v $7.4 \times 10^{22} \; kg$ 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 distae k p /t/iv y*5u1m8t,.d 15jtwq)oxgjviz,utnce above the Earth equal to the radius of the Earth. What is her acceleration dueeiziw5*v1t 8xoq.vum gu j tj1)ptd/ky ,5, t/ to gravity?

  The radius of the Earth is R. At what distance above theyxny:*8 8kzo s Earth's surface will the acceleration of gravity bex*sny:kzo 8 8y $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfk8r+q7)dv cx -2k)oexs lpg 2race equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity-r c)v+gr)x kxl2d28 k eopsq7 on the surface of Mars, is

  At a distance of 14000 km from some pla7vzvf*ij:;z sh;5 du enet's center, the acceleration of gravity5 :vs;h jiz;uv *df7ez 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 surfaceb (sejn2o+/tcr,td y)mkgslz6bm .,; of the Earth. The Earth has radius r. If the object is raised to a height of 3r ,et.n(,s;z jbc ts62/ymbol)dm gr k+above the Earth's surface, what is its weight?

  By how many newtons o: s65xau+tr qdoes the weight of a 100-kg person change when he goes from sea level to an: urxqts 5o6a+ altitude of 5000 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 3r aboveq yg)cg3(9 riy;2 xbbs the Earth's 3y2qis(gy; rbb 9x c)gsurface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass g6- s *b guwki1c*t7hland twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this plane-k*huci wb 6g7t*l1sg t?

  During a lunar eclipse, the Moon, Earth, and Sun all lie v- wj .*h9(ysluegp 0hon the same line, with the Earh0u - (s9wg le*.jpyhvth 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 transported to t;)h jh. ,sskugas6q4ehe 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 E,miwan 8 bgh:.arth (i.e., it just skims the surface of the Earth). What is the speem8 bi,ah:w.gnd 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 t6nogp ar1:lk 2he 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 radius of the Ea 62anorgkl: 1prth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surb7z.t rf zvoh3 hi +yf(bq41:pface of the Earth. It is observed to have a period of 89 min. What is the mass of the Eartfz 3o4yzfrpvh(qb.:b i +7h 1th? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter5 ak,1k3rgi wz 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 a7r;f/4 ;sqf vlq-s yrr radius of $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a planeb;5)6- 6 qhbaszpy cutt in nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it tactub66sa)bzhpy;- q 5 ke moon B to complete an orbit?

  The planet Jupiter ict)mb+k ci* 5as $7.78 \times 10^{11} \; m$ 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 yearzxpj c0b:1x hm(t628g (c xa:j9wrtius to orbit the Sun once. What is the average distance from Jupiteh8i:jxtg( uwmb6ac1xc (x jp z29r0t:r to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)