Is it possible for an object moving with a constant speed to accelerate? fg 5px0h;4momxwyrpytglo7 ,.6k i *4Explaixwo,.*7ht i4fylprm;kyop5xg 06gm4 n.

  Consider a particle moving with constant speed such t 6vi kof;4jaffc13t .ihat its acceleration of constant magnitude is always perpendicular t fvtf4a1f 3 6.io;cjkio its velocity.

  An object moves in a circular path at a constant speed. Compare the v pa*n5n9,drgyfg 16 ndirection of the object' ,pgn56n1*yg v9r nafds velocity and acceleration vectors.

  When an object experiences uniform circular motion, the 8wf2 yp (pe;cadirection of the acceleration is(pe2y a8 pc;wf

  Consider a particle moving wti1ws-y -t;rygk 7/iv ith constant speed such that its acceleration of constant mitt/w1rsk;i v7 ygy--agnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with con 3 ztaw0xq4h-pstant speed in a circular paht3-0 ax pqwz4th experience?

  What force is needed to make an objectf6;vot3r 0stvc 1t :qc move in a circle?

  When an object experiences uniform circular motion, the direction of the netwy8 ;sb(,ladnxorv;, force i;vxn,w, (o;ydbl8ras s

  A roller coaster car is on a track that forms ru6 k +fp19awva 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 vp9+kra61 wuf acceleration at this point?

  A roller coaster car (mass = M) imjco8* q 1h4;.bobvws s on a track that 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 minimum value for its spe.bsowom 1;4vbq j8ch*ed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc 0fphjc5/ ozka2) gys p*zv:dsvzz*07until it is going straight up. Just as the plane is at its lowest point, the fo *yzz zz0 pvho:*5v a)s7/s20cpfdgjk rce 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 ;sps ksd,v0-c6brzg4of 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 /kzs(7+zp 3qjg vn7m uit 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 th+p7nu( zmz7 3sgvjqk /e first time?

  A car goes around a curve of radius r at a constant speed v. Then it goeaq)fhvm7 .bh:;w.t szs around a curve of radq.h.bvmhzf:a) 7; tswius 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 a banked curve of radius r with speed v. njo00mz1 onz,jn /+ 35c-7xnq, qq akvkln2nd If the road is frictionless due to ice, the car can still negotiate the curve if ,5zn kq2czq-qo1o ,0 nn klj /na7m+n 3vdjnx0the horizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled s/i1 z:qtk-u( gxte/u run are banked at the same angle, but one has twice the radius of the other. The safe speed (no friction neededes/ku1: it (gu/zq xt- 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 ou,9cczow6a+y (orqr1im 4; lcn the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsledw (1cu 4qo9m6crl ,ciay+zo; r 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 circull (5p-x1npycz3u fla,ar path to have both centripetal and tp1uc,- flzp l(y ax35nangential acceleration?

  The gravitational force betwf/aw2i+.sxkx lur8odu;s o6 ;een two objects is proportional to

  The gravitational force between two objects is inveje;ei9 e 2 2e03uszgvxrsely proportional to

  Two objects attract each other gravitationally. If the distance bet1zd(1si:mjx:j*, / jr sz.oxzeo5 msbween their centers is cut in half, the grav1 z:xj* :(,o/ x1d jebj. m5oszimssrzitational force

  Two objects, with ma2q(o: do6cl-kmva50vpsfh9 *:uxv husses $m_{1}$ 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 mass/ykf7fa2x ;d-u0fy :fiu sw /pes $m_{1}$ 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 grlh; gkv*hu; g4avitation.

  Compared to its mass on the Earth, the mass of an object27e k -b*7-yxgjpyfrr on the Moon is

  The acceleration of gravity on the Moon is onepn8 of:lh4z .j-sixth what it is on Earth. An object of o4 8f lzp:nhj.mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from0jcebf( f61ysd7 ry2k the Earth's surface, the rocket's weight

  A spaceship is traveling to f4i es5ll/) f v9zb-ufthe Moon. At what point is it beyond the pull of Earsfui)l-/vlbef 5f z94th's gravity?

  Suppose a satellite were orbiting the Earth just abovep8al( t;1-f,pwa ytgv the surface. What is its centripetalpt l-vf1t wa8yag;(,p acceleration?

  A hypothetical plane+l/cbz+kh a d5t 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 g, the acceleration due to gravity at talhkd5b+c/ z+ he Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth.ap3w)o+sdpk7 The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass co+3) apodks 7pwmpared to the Earth's?

  Two planets have the same bv4*je (rd6 ,tp8egh 1nv7nzksurface gravity, but planet B has twice the radius of planet 8(rk enhn, 7pe*tdbg6v41vzjA. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but p *4mbhlz+7br xlanet B has twice the mass of planet A. If planet A has radiushzxl7mr* +b4b r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) a6 z 5xb+tbqyj) dsiqo80 0cv/ybout a spherical planet (mass M). Wh+scz 65 8 tbdy)/xqq0ibo0vy jich expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rohs 7fvg j8r7+ qrtljv34. igd*tates in the same orbit. Compav+fr l3 4gsjri7 qh7.t8dv*gjre the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downwardh k4 qfyix) efl v,afug1,20c(. Compare the re , (,xkvih 20calfeg fy4qf)1uading on the scale to the person's true weight.

  Who was the first person to realize that the planets move inq8e/cog7(s0 ga5 tabf elliptical paths around 0(b/a85q g e7 ogscaftthe Sun?

  The speed of Halley's Comet, while travpn:h / ytz4hy.,1 lvjh4v:dk oeling in its elliptical orbit around the Syo1h hyvvp/lnjt:kd. : hz4,4 un,

  Let the average orbital radius of a planet b1 c287(z .u)espu anl- lk(o msihge2we R. Let the orbital period be T. What 8)kei(7gueuco2 (lzhamp.s ns-l2w1 quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbi87f; wx6j9nzadkw)r o t around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that owwa)n7jf6x zd r8;9 kstar 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 to the Sun is defined as one "astronomical uvod(0giu y9ob) r oi85nit" (AU). An asteroid orbits the Sun in one-third of a year. What i(9ugyb 08 od)oivi5ro s the asteroid's average distance from the Sun?

State Kepler's laws.; el0jsg hf *(b3,vbky

  List the four fundamental forces in na0ragwh95 xeo4cff(p9j f38m nture.

  An object moves with a constant u2t ofh*u.d g(udw,(s speed of 30 m/s on a circular track of radius 150 m. What is the acce. ug(hut*s( d2f,duowleration of the object?

  The maximum speed around a leve)mj f z2hkcrcu) p+r*:l curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchang c):mf)jrhupc2k+* z red.)

  What is the centripetal acceleration of a point on the perimeter of a no 6.m s a+hv14y6fcgxbicycle wheel of diameterg.h6m nvsax +c4o61fy 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is wqj7h5s/6r (esfv z-slocated 0.200 m from the axis. What is the centripetal accelerat/f vs j7q5es(-6hrsz wion?

  How many revolutions per minute must a circulj ;mr h1pj1 7i6xh+hpfar, rotating space station of radius 1000 x;+ 6hi1ppm7 jjfr1hhm rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around busit) cp:,r :s/cpe50k1stia 13.7 m radius turn at 96.5 km/h. What is the centripeta1b c0 u::ise/ppist,5k)str c l force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m st yx xtfnal2w-/ vr m/afa,d-rt.6otg;7-gfq7 ring. The system 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 if the string is not to-f/7, frt2xn/x fv ymalt 7a-tgd .qrow6;g-a break?

  A stone, of mass m, is n.sqn d9x ,bn6attached 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 3 times the stone's weight. The stone's d6sqnx,9bn.n speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in aeip-d3baj1 6 qqvg61l vertical circle of radius r. At the exact bottom of the path the tengql1ed6-3ijb1pa6 q vsion 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 2v9yj+jnpg1 1lleoll: h ( *pwm/s experiences an acceleration of 4g when pulling out of the dive. What is the radl(owl*l1e+ hy2jp1p9 v:n gljius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in wh )uaotc, 9g6odi06p1 rcmmw z4ich the center of the loop is beneath him) of radius 3200 m. At the top of his looo) wzc6m6ugc,4i9r p1aod m t0p 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. hh r5gk 0a2ps3What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/a p5h2gksh30rs?

  A car traveling 20 m/s rounds an 80-m radius hkd 6c(ztz ,gpl -fw+u0orizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume thek p(z -0zf tdu+lcg6w, same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 mtm0j- vyp7eoindz 293eh* r4e /s. The centripetal forcpejeizo397*4 h0yd2tver mn-e 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 ,w8y0l or)n amradius 50 m at a speed of 14 m/s. What must be the minimm8r 0)oa,w ylnum coefficient 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 coj5xc7 sfc6p (kefficient of friction between the tires5s6kc j7x(fpc 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 bobsle/p1 opw4*bydic:(n:g nvdsy -d to negotiate a 100-m radius turn at 35 m/s without skiddin svcy/gd n4y::po*bi-np(dw1 g? (Ignore friction.)

  A horizontal curve on a bonj5c9z )+4m0tqy gm*jwjsm0d bsled 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 angle ofuc.zrvc)uje2 y7uu :0.+ obbn $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankedqbh(-dwj1 r j4cee -t.d7c,i- brf3 rj 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 un k.7:) outyxa7wsce,h5w egb3pk*ku.iformly in a horizontal circle of radius ) *ywu :c3xsk 5 h.tku.ew7a, kb7geop0.500
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;b1avz- 5p mlt accelerates at a uniform rate to a speed of 45 m/s in 15 s, ap;l5t-m b1z vmoving 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 c ier: c/d wadzrfyv;p.y4d4(0e5oi7 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 on 0zyr-u1fja;*th n/fi the Earth, due to the Moon? The mass of the Moorfif1y-a *nt;/uh zj0n 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. x+fyq-c wax3 /uf03q+vw4y cc If the masses are moved to half of their initial distance, what is the gravitational attractive f+3wa- 0qqc +yv3x4x fcywu/ cforce?

  For a spacecraft going from the Earth toward 9e9 gnnm 0uy/ethe Sun, at what distance from the Ear09nuee /9yn gmth will the gravitational 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 isc:v8hds 5 +gyy $7.4 \times 10^{22} \; kg$ 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 distance ab,e/loc saff8o*d*3 pgove the Earth equal to the radius of the Eartgo*s*3f ,lfap8o ce/d h. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth'sq)l qdupvb4hp8q zhx )-b01 3 s)+)lbemgg*bp surface will the acceleration of gravityb qhxspu +8 zbb-)p)q4 gv*l)gh0b p)d3q1elm be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance ixvmh ;72r59)me vs 43tbiftn above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of bse2mf7 ;tv5x n4i)tvhr93 m igravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the accelerat ztla;,ll)jw7a ,/rg/vcxw lcvol 1r *1c1f0pion of gravity a * t/1oc,l7,xll)wa;wr0lccz j vv/fl1gp1r 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 ++(y8pga4w xgp, pjm.m q ype;on the surface of the Earth. The Earth has radius r. If the object is raised 8wp g,g4;mj+y+ (epyqmaxp.pto a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the wei*xp + xwjuj6w/ght of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of t+x6*jpxw /jwu he Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r ab ta,qzfpw j*fg(x3v66kza2)oove the Earth's surface. What is the satelzqa*)f,w6o g3p( f 2kzj6tx avlite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its rarz hcz 9tdazv ;pm;x;+3xt34kdius. If a j 3 zx xa;mz9rt;pdvt3;+hkc 4zar of 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, the Moon, Earth, and Sun all lie onung/ymvr bz2wym: :( +z/5xt o 3xank1:vhu:n the same line, with k:xu2m:: hoz3n tv1z:m+v/5 by(y/nxwuna grthe 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 is transportep) *cn m -s3ezvaz;n1ed 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 just s0amsng;p+xk 6 kims the surface of the Earth). What is the speed of the sate;x 6 k+ng0pasmllite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a lo*cagg kc7+d,t 21 n/ti bpa5kpw circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make 5gpb * c2,/ipa k+ktt7d1nagcone revolution 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 qq d);mpu/ s0iEarth. It is observed to;/0qq sipu dm) have a period of 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 orbital d n.fr*(iq gfj0iameter 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( clf *jj0ors- orbits the 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 plags 0h,zpvpu41awd/q eu+oi2. net in nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A take2osp iue/, dua14w.vh pg+q z0s 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 1/(4; 5-jji vjlcqd6oc bjht*w s.wrk$7.78 \times 10^{11} \; m$ 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 years2ah bdn32jzo0 i t o78ojg,u2w to orbit the Sun once. What is the average distance from Jupite20i38anjd2uzho7 ,bg t woo2 jr to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)