Is it possible for an object moving with a constant speed to accelerat+c8cm .g 3y1doi5op9iyar-;ly w zx p:e? Explainr 1i-pox98yzc.ygiowcda+m y ;3 5 :pl.

  Consider a particle moving with constant speed such that its accelqha/r hvr dovomm0gq1-ziv(8o3o o203p/ u+geration of constant magnitude is always perpv v/0riaqm 3 83d2r1goq+muohp0o zo(g/h -voendicular to its velocity.

  An object moves in a circular path at a constant speed. e)faijsbn 90( Compare the direction of the object's velocity and acceleration vectoa0be) s9( nifjrs.

  When an object experiences uniform circular motion, thp:.b2a qco;3sz a.gw l2g ,toqe direction of the accelerabo c2ogs .,2a l ztqp;wqag:.3tion is

  Consider a particle moving with cons:lkd,ghl2i-zhv ip.23tlo 3atant speed such that its acceleration of constant magnitude is always perpenhal .-vo 3zld l h:2iikp3,tg2dicular to its velocity.

  What type of acceleration does an ie:c h2flk wks:8rd *sy;e-6yobject moving with constant speed in a circular pc-es6*w :l2ki rf8yy d: k;eshath experience?

  What force is needed to make an object move in uizw:( *l5nhp a circle?

  When an object experiences uniform circular motion- m8ac4n9b qey, the direction of the net for8eb-amy 9q4cnce is

  A roller coaster car is onfjiiy5 52w(j )kugw- yygb, 4b a track that forms a circular loop in the vertical plane. If the car is to just maintain conta45 i byfk,juywgygibw-( 25j)ct 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 that73 pe 6kut ooabgrv//, forms a circular loop (radius = r) in the ,3ougrt6/ vko/ e7a bpvertical 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 speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc until it m ypi h2*a9 jkbqm5i9/is going straight up. Just 5kjmiihpq9/a2b y9 *mas the plane is 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 radi 3sei4v.ara8 6d qvk4hus $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radi s5 hr/5m xcnd ,cb8ud,re8hg9us r 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, co/ugdc, h,r58nexb cm s9rhd5 8mpared to the first time?

  A car goes around a c07*q8snxnwq 4 jgr -gch nm l::n6q8ycurve of 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 around the second curve, compared to tcn -j4n*qs: r:nl c0n yqmgwg8xq7h86he first?

  A car of mass m goes around a banked curve of radius r we3qd5z*piu uf 2drcgq* , ba3ek;(jy*ith speed v. If the road is frictionless 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 eyf (5q3zgdr*c e3bj2*,* ekauqui;pdqual in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, bu(kt5(jv3j-l7 *jbyp ifjct5nr 5o.sc t one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius curve -5jb(lpk t f.*vj jyo ric 75ts3(n5jcis v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled trackxxav z4 uv0/ e,hfvw640;hhyx is not constant, but increase46 ae0vuy h hz0;wh/vx4,xxfvs 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 do this?

  Is it possible for an object m.tk7n1ukn+kv oving around a circular path to have both centripetal and tangential acceleratio+ k v7un1k.kntn?

  The gravitational forik7 h6(bi55qx jezn1gce between two objects is proportional to

  The gravitational force between two objects is inversely proportigvvc4 7opmx:u 0 ul5j*onal to

  Two objects attract each other gravitationally. If the distance betwk ykl(eh:oc 9)een their centers is cut in half, t)chok:y( ke9 lhe gravitational force

  Two objects, with mass9 y643kh nyz:z sae7ak9j79wo hnj*v pes $m_{1}$ 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 masnngy,x k,tt/v) 5e k;6u*hbbk(x j 8peses $m_{1}$ 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 *+q2e lfa;gvnsnsl* 5kyk3:i gravitation.

  Compared to its mass on the Earth, the maffy8f qv .n/1fss of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth w8g lhzv,o j3cy5u k6-vhat it is on Earth. An object zoj683vl hc-5 ygv uk,of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the g67q)ura, y lgrocket's weight

  A spaceship is travel*mp)h 8. jbd zd.g.khxing to the Moon. At what point is it beyond the pull of Earth's gm..x k)hpz8b j.*dh gdravity?

  Suppose a satellite were orbit 0j2aay + btjpp4wgit-4pmhfl7 8c71iing the Earth just above the surface. What is its centripetall2pat 4j4pit -h7 g w i7bya+cjmf18p0 acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius of*1xv je4n +,idob xcm, 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 thebve*+x co1 x,m,jnd 4i Earth?

  The acceleration of gravity on the Moon is o36d nzqkm:. k ry: 0:nlvd*y:e6q gzrmne-sixth what it is on Earth. The radius of t66 nk nd m:0*zr m::3gqvdk.l:yryqzehe Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surfaqkvh.: a4gr p(ce gravity, but planet B has twice the radius of planet A. If planet A has mqv4 ah.r g:(pkass m, what is the mass of planet B?

  Two planets have the same surface gravity, butns - yuz1j,d391d ezte planet B has twice the mass of planet A. If planet A has radi1s 9jz3, 1tzyenu -eddus r, what is the radius of planet B?

  Consider a small satellite moving in a cer* t.k/cgbkc: 2r1e(,yxgfzircular orbit (radius r) about a spherical planet (mass M). Which expression r2 b fg t,k/kc .zeec1(gry*:xgives this satellite's orbital velocity?

  Satellite A has twice the mass oa6 zrkpf:o,bby.k5 c .f satellite B, and rotates in the same orbit. Compare the two :ypzfobra.,k65kcb .satellite's speeds.

  A person is standing on a scale in an thcl 2h( 6ufg/u+pjp/ elevator accelerating downward. Compare the reading on the scale th2ppc6 lj/t +(u ugh/fo the person's true weight.

  Who was the first person to real3 bhy yv81,w.wql j7ssize that the planets move in elliptical paths arous87y13lswh bv.yqjw,nd the Sun?

  The speed of Halley's Comet, while ydo b:--c x k0;hzzwre:wx 28atraveling in its elliptical orbit around the Sun,xad 8wxow : ;yh:rz-02-e bkzc

  Let the average orbital radius of a planet be R. Let 2(pxrh6e/f 5w8-qiymga i5xc the orbital period be T. What quantity is constant for all planets orbiry/x 8gae-cw6hxp(qi i5 5fm 2ting the Sun?

  A planet is discoveredsq ym3emh/38vr x* pf/ to orbit around 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 bep3/*yqhs evxf/ 3r m8m, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as okh*n7hee(y/;. klqbwne "astronomical unik7w ylhqh;*/.ken(eb t" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws. .-y h3fthfny2

  List the four fundamental force6)lhh vrh wz+1s in nature.

  An object moves with a constant speed of 30 m/s on a circularzr c*:r2;w xny track of radius 15 ;zr 2:*nyxwrc0 m. What is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximumg mkx (nj:9d.h g4+ea*z/f a+up3gyah speed around a curve with twice the radius? (Assume all other factors remain unchangedm *h(dangu+ +gh9e4gf k3j/p.y:azax .)

  What is the centripetac t+wi0f6b k()jizr.hl acceleration of a point on the perimeter of a bicycle wh+ 6z)hbirj.w(0tikf c eel 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 bs7skl 8 s782sdindfibv)-fn7 ei56t.200 m from the axis. What ii8enn78 6bv fb)2d-i sik75ft ss7ds ls the centripetal acceleration?

  How many revolutions per minute must a circular, rotating spxi)f xe ijq5j*x 85pe6ace station of radius 1000 m rotate5 ex *8iqi)xp6fj5 xje to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m d(2pzf g rez82et jhl8n,(s6x radius turn at 96.5 km/h. What is the cenlzs8 , jpdef(x rh2862gtz(entripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. lj .spcl0-hk : s:-tye The system is whirled in a horizontal circular path. If the maximum tension that the string can wie-lc-pssh .y l:0 jkt:thstand 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 in a v0 ntebln 6rgk+zyzeg 9 -f2;m,ertical circle of radius r. At the exact top of thtelf m- g+ ry2gnzn6zk 9,e0;be path the tension in the 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 muf- zq:c/7aw -ozwct30w-jr a vertical circle of radius 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 byj3ro m7acq/--wz t- zcww 0u:f

  A jet plane flying 600 mqqc53x2:7spqo o)8:a ws uwdg/s experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is g5caq so 27sd8xq)3u:wqw:op flying?

  A pilot makes an outside vertical loop (in which the centerzht(t9c3wh7s of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat with oh c9zwh7tt(3 snly one-half of his normal weight. How fast is he going?

  The maximum force a pilot can (a*)xk t xiq b-hzuio)af52u1(*bdnm stand is about seven times his weight. What is the minimum radius of curvature -) id xnb*(*autihub)z21xmk( f qao5 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 horizontal cuyh b*m; khw4blm/+2bf3+ gmqsrve with the tires on the verge of slipping. How fast can thisq w+m4*hms+my lf3hbbg;k/b 2 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 flat curve of radius 50 m wit7)- 5zlox2/l, jwsp i qbddey9h a speed of 20 m/s. The centripetal force provided by 5zsq i2o9bj,xpdl/dleyw- )7 friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat,lre.0ft4ij( x-qgc e curve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficieg,t qxljecf(.-ire40 nt 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 coeffici kcpf(q74lf f:ent of friction between the tires and the road is 0.40. What is the minimum radius of the curve iffkl:c qfp f7(4 the car is to stay on the road?

  What minimum banking angle is required for8zkl ;4f ;pfk8 ;tyrajuy si*, an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (;sfa4* r kf;i 8ky8u typ,;lzjIgnore friction.)

  A horizontal curve on a bobs0 h++r xzw /7jssdtu6dled 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 radiushkas tvze:+7(dz3 4zv8i q8ia 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is y7lym.vmdnc) w.-kincw) v0 79d/t fd 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 revolving uniformly in a horizo/qo8-fj er el0ntal circle fjq0le/8-r eoof 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 accel9jpdh s.t z)/werates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 h9z )j /.dpstwm. (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 consimk8 *kc3zvr em -v8n8osts 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 gravitational force on a 2y)-r rp zkr2vll5 v fo*q;6ye70-kg person standing on the Earth, due to the Mooq5ek-or*22r v)6 yflzpy lr;vn? The mass 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 the mas kcd.m**wss; cses are moved to half of their initial distance, what iws cd. ;m**skcs the gravitational attractive force?

  For a spacecraft going from00y)nj k5por p the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun 0 5)jkroy n0ppand 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 is z2x -,e1;v(rjhot vbq$7.4 \times 10^{22} \; kg$ 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 ou5u5/8 jmo .t4jbujxsl f9w1uqt for a "space-walk" at a distance above the Earth equal to the radius of the Earth. What is he9 u1jlu5fo5x jq8/w.4s bt mujr acceleration due to gravity?

  The radius of the Earth is R. At what e47q7 pka(g*cn ;r wg-h(lfycdistance above the Earth's surface will the acceleration of gah(7 e7cgfl4w*kncp; q (- rygravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface eqm8ks(l8,,woo: b wrp u)hvfi ;ual to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surfac)ow,,iwf u8:ps8(br;ov kml h e of Mars, is

  At a distance of 14000 km fro-pva.r /dbb99y ygu.*ai. rqam some planet's center, the acceleration of gravity i-aa9ugb*yr qybr/9 p .aiv ..ds $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surfa z is2q*9c5irxce of the Earth. The Earth has radius r. If the object is raised to a heigsq5*x z2c ir9iht of 3r above the Earth's surface, what is its weight?

  By how many newtons does the .euqbj;9 cy)xv.()sitq. g 2 z0qak rlb66mbv weight of a 100-kg person change when he goes from sea e kvc(x.mgq6au qy6 ljzb. b2 0 9vi))qr;bts.level to an altitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. sk. /m8y)abk1f) 4sub t w-dcuA satellite of mass 100 kg is at a point 3r above the Earth's surfac k8a -4)btcs1./)u uwsfbymdke. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice 2..ipqp o u,8cox (qfivn -au,its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the xq p2ac,u o(opvqif-.,.n 8uisurface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same line,i*,y bn s3y3cy0 0q1;z vumpse with the Earth between then i*, 1yy33 m0zcuvss;pbqy0e 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 tor:g tsjsy+3;n 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 t:+qmy;ph3 ry(/b yeqoo35yzkhe Earth (i.e., it just skims the surface oky(pooy5yb qy: q ;rm/e33z+hf the 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 low circular orbit about the Earth (i.e., i 8 nztcm*8g4.m omgni-t just skims the surface of the Earth). How long does it take to make one revolution artgm8 nmion.c8-4*gm z ound 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. It is+po gt1veojx93 4hh s4 observed to have a periodp ehov4oj31xh +4t9sg 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 diameter l5;fdetkwwd1)c, d +d 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 radius offs wl /4o49sbo $422 \times 10^{3} \; km$ 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 radius rrj* ebb q:y,y1, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it takey y*,bb:1jq re moon B to complete an orbit?

  The planet Jupiter ix*9kb/fr i9 rm7 k9:k 0toghlas $7.78 \times 10^{11} \; m$ 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 the averag9mx e4d:)wstp e distance from Jupiter to the Sun? (The distance from the Earth to the Sun is 4w mex 9)sdpt:$1.5 \times 10^{11} \; m$.)