Is it possible for an object mo7y *nsqj u27bh1;plvpving with a constant speed to accelerate? Explain.bp 27p nyv7*sjlqh1u;

  Consider a particle moving with constant speed such that its acceleratvs.q0m62u7f jkocy f ,ion of constant mkqj27f ,mufsy.0 v co6agnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare the direcyb z3;btt*2rnq m2(m ky6i7*fof5zh xtion of the object's velocity and accelerati7ozyi5tf b(3 2x mb krfqymz*;tnh62* on vectors.

  When an object experiences uniform circular motion, the direction of the eq5qei1iih bg./ou7b.8 (hc 9 vgnz,laccelera iz.9 l qb8(coh 15.gui/ei7qn bgvhe,tion is

  Consider a particle moving with constant speed such that its acceleration of cojl*mni : 6qh +z5ehil.nstant magnitude is q*lhz. il5+ ie m:jh6nalways perpendicular to its velocity.

  What type of acceleration does an object moving with constant speed inf8j4+kwc29 tp2mxoqpj+6l qb a circular path 4lj+ fw2 bo+cp jk 2txqq869pmexperience?

  What force is needed to make an7 jqw26bswxu3 idb o)5 object move in a circle?

  When an object experiences uniform circula:8aq/sy4l0ze1q y :nelvm o e8r motion, the direction of the net force is8yqalq :so1nlee/0e4vm z8y:

  A roller coaster car is on a track thaz2fk p .u8m;ptt forms a circular loop in the vertical plane. If the ca.8k;mp2u fz ptr 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 (r;(jd/yxq fk6c8 mss rn 4 tqazcf7.c99adius = r) in the vertical plane. If the car is to just maintain contaccs c9nd6q;.jkt q98f f/sxr4(zac7myt 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-96 hiutnmb0v c(eq0o then follows a semi-circular arc until it is going straighttc9h(onm bv60u 0-qi e up. Just as 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 rad+u2+t 7)ty,m gzgwrkrius $r$ 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 it goes aokur8z (s+ 9drround 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 the fs9 o(rr8+zdku irst time?

  A car goes around a curve of radius r at a constant speed v. Th:c-rqvafa0 m b,q*ng0 dhun(6en it goes around a curve of radius 2r at speed 2v. What is the centripm0:-unf ,grvc6 a qaq0b (*dnhetal 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 raixs* /f b2 y,.-is8ialrikhrz*0 uwv(dius r with speed v. If the road is frictionless due to ice, tir*a *2uz8/ ,si rw-0vk.b(l hifxsy ihe 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 run are banked at the same angle, b3 ei9+k k7kjgbut 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 ke39gkjbi7k+ is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympiuug2a.7 stulu12e -kcc bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," k.u c u2aulgsu2-et71 then go lower coming out of the turn. Why do they do this?

  Is it possible for an object moving mzdp .zi .)t5yswj;;/c +xg jdaround a circular path to have both centripetal and tangential acceleration?w zd z)csx+5i. j.; mgdjyt/;p

  The gravitational force between two objects is proportional tpb;a .sgiy2dkl:2e/u o

  The gravitational force betw-0m1xtep 59 cyf s/dpneen two objects is inversely proportional to

  Two objects attract each other gravitationally. If the distance between tht 0qoaaeo, 2ra0v(7u heir ce07 v ua,0o(a2 orehaqtnters is cut in half, the gravitational force

  Two objects, with masses qh-pt pj6 7-w0vcsyn1 $m_{1}$ 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 ma8s, )c/hsq wylsses $m_{1}$ 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 0 msz;,vsjcorl/yf.4txdn ,1 universal gravitation.

  Compared to its mass on the Earth, the mass of an object on szt*wsy2 s aq8(od/ 6athe Moon is

  The acceleration of gravity on the Moon is one- u, mvel2h7zr7g00;lbkq tiq5sixth what it is on Earth. An object of maetb v0;qm2l lu57rgiq7kh,0 zss
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surgo:wgchc0ryc ( n4u 30face, the rocket's weight

  A spaceship is traveling to the Moon. At h/rup) /tgu5j5,asmlieh c:1 what point is it beyond the pull of Earth's im5/ ,:sueac jru/h15 )tlghpgravity?

  Suppose a satellite were orbiting the Earth just abovvme)0)yiw k;wlmhnu ) v i,22te the surface. What is its centripetal accemkuh;y, w)wi v )vi)tn022emlleration?

  A hypothetical planet has a mass of half that of the Earth and a rad(0l2 i i nmq(qcfmx/v:r;s/udius 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 anifd2((c0;mq u// qs :l rimvxt the Earth?

  The acceleration of gravity on the Moon is one-sixthl:wpn2-jag4 rny ffb0d1x5h: what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to th5x-::n g dfhrlfw04nap2bj1y e Earth's?

  Two planets have the same surface gravity, but planet B has twice th+z w;2l k. gxjg4zfz+de radius of planet A. If planet A has mass m, what is the mal+f+z4zxjgz.2;g wk d ss of planet B?

  Two planets have the same surface gravity, but planet;c3pzx9*odm 4 jzymkr(j6zo( B has twice the mass of planet A. If planet A has radius o(kmjj 9x(*6r4z d ;pczmo3y zr, what is the radius of planet B?

  Consider a small satellite v-05g5 zd uqvmmoving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satev0 m-z5g du5vqllite's orbital velocity?

  Satellite A has twice the mass of satellite B, and ronhru-i33xh wqe1uc8wzm+2. /s pju- otates in the same orbit. Compare the two satellite's speedhp1i8u-wjhwoe3.rus c/2n-m+3z qx us.

  A person is standing on a scale in an elevator accelerating downward qe4u z3t06rwkiqt2hb.ggz j : h7g83j. Compare the reading oh708 q2g zjb3q ztg t3w:g4.j6erihukn the scale to the person's true weight.

  Who was the first person to realize that 1fb kp *2exl**e)haea the planets move in elliptical paths around the Skbla e2e*pa )h*e 1xf*un?

  The speed of Halley'p1v+dwp 73.aaob4xk avj 0 3pcs Comet, while traveling in its elliptical orbit around the Suw apv34x1 vb0+ kdcp 7a.pa3jon,

  Let the average orbital radius of a planet be R. Let the orbit :g30,xyshkxpal period be T. What quantity is constant for all planets orbiting the Sug0xh:psy,x3 k n?

  A planet is discovered to orbit around a star in the galaxy Andromeda, jw *+:nu,6.jhendlcxwith the w.x l6 ehuj cnj*:,+dnsame 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 period?

  The average distance from the Earth to the Sun is defined as one jx,wq--2dk z v"astronomical unit" (AU x-wq-,j2dzvk ). 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.7,+bbntkeb k4

  List the four fundamental e5v fnz0+i bf+dh-znohuuxj8()81rz forces in nature.

  An object moves with a constant speed of 30 m/s on a cl4j6cqp hyr+; qn 0lgnv36:z zq5xy7oircular track of radius 150 m. What is the accelerationjg q+x;z56qqy:ln07vlz36 cnry o4ph of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maxg3wpp/xh* x1m imum speed around a curve with twmwx p/p1x3 h*gice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on therq 2tnkm,6 gx*k io*3k perimeter of a bicycle wheel of diameter 70 cm when trinm2 tg6kx o,q *3*kkhe bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locates4ukio8:u dni h i*5igz62 .fld 0.200 m from the axis. What is thehind2fosz*kg: 4.i u8ui56l i centripetal acceleration?

  How many revolutions per minute must a circular, rotating space statra,qs g-rl,ona (mm 1*ion of radius 1000 m rotate to produce an artificianramm1as * (-,q,grlol gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 7hz8v1 ijy5sy250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centri8hi57s jzyv1 ypetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. Thc1 n*m q1i8myee 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 t* my1mqi1ecn8 he mass if the string is not to break?

  A stone, of mass m, is attlt4lq amq589ncah8w +wdgx ).ached to a strong string and whirled in a vertical circle of radius r.+m8a9xt)w ndhw8lq4.c 5lqga At the exact top 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 stone, of mass m, is attached to a strong string and whirled ijp,)y , l8bhcv 2yg:rbn 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 j)2h:ryc p,bl8y b ,vgstone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration oopyvo2kcv, 0 lf)l-*j f 4g when pulling out of the dive. What is the radius of curkpl l0-,vocyv )*jf2o vature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop ,crco 9p*/cdc3 k5i xd(in which the center of the loop is beneath him) of radius 3200 m. /cc*95ci dkxo, 3rc dp 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 times1hre *im-y js .5wenbmf;9:x+di w 9oe his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tole.ri- +ej9o 5mxy:emi1n e*dwbh9 ;swfrate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curv qvl/(pi8s;iksy/u s0e with the tires on the verge k0q/yvsi8(s;l / is upof slipping. How fast 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 flat curve of radius 50 m with a spen:g7 3nlal1rnd :v8gl 8dm4xt9/l mbzed of 20 m/s. The centripetal force p9xn:l 88dgb4g l azr mdln7/3m1nt:vlrovided 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 14 m/s. What must7mxkg8,cs(ag,l hj/a be the minimum coefficient of frictiohaa/(g 87gm,l,j kcx sn between the tires and the road for the car to make the turn?

  A car is moving with a constant oc-fp/e /eknac3jz/dro;81 kspeed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What kz/ /ne/ jcocdk r;a1o8f3ep -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 negotiate a)*oyhupten ,n o93qr: 100-m radius turn at 35 m/s withoutyu9 3)n,hepnro*o q:t skidding? (Ignore friction.)

  A horizontal curve on a2*.nc.ch v)vp1l zvvv bobsled 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 ofyq 38 x82zw7tp7/hfuvd4yy eyn ,v d;z $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b1*clo n0dfhk f; :n8lsanked 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 horizontal c;9vb s9 51no7 dmnxqjrircrn 9j19 qx v57dsbmo;nle of 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 accelerates at a unifo2+. ps 2;tpdevgwzv/orm rate to .2tdzg/ovpp;+ ewvs2a speed of 45 m/s in 15 s, moving 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 kldvt4*c rof vgt8p/+2ap + )ua 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 6 /jh;wqaj.3 twq4xt 9o+jg-vixl1m2apkwf3 70-kg person standing on the Earth, due to the Moon? The mass of the Mooa.tvi p- h3/wftjwlg q4kx9xj;2j1 q3aom6w +n is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attracte:k w03z0gei kive force between two masses is F. If the masses are moved to half of their initial distance, what is the gravitational attractive f 30 :e0kwizgekorce?

  For a spacecraft going from the Eartc 5b)sav7tw 2oh toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth cavcw7ab) s 52otncel?
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 ggtczn;rq)00 $7.4 \times 10^{22} \; kg$ 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 abo(4kskyn unvwz aiz/-8+w s*9a ve the Earth equal to the radius of the Earth. What is her acceleration due to gravitynk+(8za k ws/-uvnia y*4 9wsz?

  The radius of the Earth is R. At what distance above st3f7n1s .aqla.0 svpthe Earth's surface will the accelera.s3al.t nsfv1 sa0pq7tion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above it,;wp is-vpd1 ne8 e8fcs surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as c,8vis - f8neecd ;p1pwompared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some pla3of zuqk/f.d0wce.m7 net's center, the acceleration of gravity is w qfoef/7m .cz0.dk3u$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the su t3 no;ow:) xru s8tpx7s7uqj.rface of the Earth. The Earth has radius r. If 3r8ux qjp7o:.;s7sxtwt)nou the object is raised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg h+i; gq( v 2imjybrk8,person change when he goes from sea level to an altitude of 5000 m? (The mean 8i2+h j(kgir;v,y m qbradius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of 6hu af* d/*6h rgp1yluer dj+p76v*oe mass 100 kg is at a point 3r above the Earth's sury+6 1h*df 6 l7*vodh au6pee*p/grrjuface. What is the satellite's weight?

  A spherically symmetric planet has four times t*la k qg3dus9tjhnhy2u7n /(/he Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Ealukyht/jd*q9n3s n h g2/ 7au(rth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all li63: dw wd,h/h1zzjmwbe on the same line, with the Earth between the Moon and the Sun. The Moon has a mass of / h:wjdwmb,zw36z hd1 $7.36 \times 10^{22} \; kg$; 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 the Moon.x5w .znrpmj9.
(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 c, ecpkef2zw+8w;t o -obd -oi(ircular orbit about the Earth (i.e., it just skims the surface of the Earth). Whc+8 pbewotd;oz w(-f-ei2ko , at 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., it justwpul9z..+ b+a7,l 1 iy ukaxpq skims the surface of the Eapub 1.pl7,xq kaylu+ i. 9zw+arth). How long does it take to make one 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 Earth. *+numb:q3r ci It is observed to have a pb rqm+nci3*u: eriod 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 e3q)d;lv8 a4 q of. eihq;eja3qn,v -xorbital 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 Jupic+0c 9n(.k3zxx d55inetdm svter 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 planet x:gvndlc jk+hl 2:7(p in nearly circular orbits. Moon A has orbital radius r, and moog(7d :nhxl :jvlkcp2 +n B has orbital 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 i3a/rqjgv;p/0 5da pafs $7.78 \times 10^{11} \; m$ 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 orb nwe 6);n0sssqtl)t:ait the Sun once. What is the average distance from Jupiter to the Sun? (The distancen)s w);enst6a : qlt0s from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)