Is it possible for an object moving with a constant sn)ln87pg* npn6x 1 rnypeed to accelerate? Explain7nx1pnrg6nyp nln)8* .

  Consider a particle mos. .. huqotstq g8jhnn(37k6r( *es roving with constant speed such that its acceleration of constant magnitude is always perpendicular to its velo8r u63qehn s.kjsq. s7.(n tgtro(o*hcity.

  An object moves in a circular path at a co)khww .a* mo-knstant speed. Compare the direction of the object's velochw*kak-m. )owity and acceleration vectors.

  When an object experifrdl 7bd+xx7c0. u3i gences uniform circular motion, the direction of the accelerildc r b0gu.x73d7fx+ation is

  Consider a particle movin-4s yueg)lal* g with constant speed such that its acceleration of constant magnitude is always pe a)4ysg*llue-rpendicular to its velocity.

  What type of acceleration does an object moving wit 6)k ibf0fb *8awfpdk2ekw0k 7h constant speed in a circular path expe8k 0kfdkk2we* b0)f6bwia7pf rience?

  What force is needed to make an objec7 dk4h:gc7bt0*g kny9 fg 9kqmt move in a circle?

  When an object experiences uniform circular motion, the direction of the nhhmuw q2f( dnbru05;/o1 -bx oet force i nmq;x hdwob/ 2rfuob-(u1h5 0s

  A roller coaster car is on ap e2) noscih1osd -3/k track that forms a circular loop in the vertical plane. If the car is to just maintain contac1c3ik/ss-n oep2 od)ht 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 =s3adc:8 ejt6x M) is 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 speed at that ax:c6e tsj38d point?

  A pilot executes a vertical dive then follows a semiwnrpgfh8v 30.sn2l+ +3il uz*;u yyn a-circular arc until it is going stu.vpygh ni y*0u+nnl 2lsz3;frw 38 a+raight 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 rak8s*)xttw+ss- a 9hn cdius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radgc , -c 0ad nlec*x1-nymc4pqsiuq96 :ius r at a constant speed v. Then it goes around the same curve at half of the original speed. up lqm:0cyca-sde4iq9 1c*gcn xn6 , -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 radius r at a constant speed v. Then it goes a) bg j*io5pz57htqj2fp f +l-vh ee +z15kmc(hround a curve of radius 2r at speed 2v. What is the centripetal forc+1)gj*7ek-ect h(+m j 5fblv5 z oz qhpfi5ph2e 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. If the roauhmjc704i pp2 d is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force j7um2p h p4ic0on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled runhtf3 5 7uxn .fugq og ax0+qc8i,6jqg( 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 thio u,fqux g nq8 xc(+jq5 f6at3.7gg0he smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsg ;b2tqk: :droac. bx//2utrqled track is not constant, but increases upward frqt2u.g x:c2 ob: a/;/rkt bdqrom 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 ankhs, j,jntmn 1nqr,ym9.) +s5 vb(bda object moving around a circular path to have both centripetal and tangentia,ma+5n,r svm,dbnsn9 jqb1ht(.y ) k jl acceleration?

  The gravitational force between two objects is proportiox1hv 8u7zc;ctnal to

  The gravitational force between two objects is inversely pt, j)sol/ h)rtroportional to

  Two objects attract each other gravitation y:a,58rj i )-(s4xur4tfdpi-zyx n xfally. If the distance between their centers is cut in half, the rxn ixs-xjfr :(-8yi u,) az544yftpd gravitational force

  Two objects, with mass3gbh zoqso o+v6 j9*y7es $m_{1}$ 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 mash b5h7+q dmmo(9:vkfm,2fy-m nw 5nszses $m_{1}$ 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 universa uotqfh*: uy*3f(pc7 kl gravitation.

  Compared to its mass on the Earth, the massmrir68 8eaz. w9bae/b of an object on the Moon is

  The acceleration of gravity on tt0yj iel(zf2b)i iz;7he Moon is one-sixth what it is on Earth. An object j ebi2;0 yfzlzit7i) (of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away bj)/hwgn , 4g+m v+cmzg62iarfrom the Earth's surface, the rocket's weight

  A spaceship is traveling to the M9p0fzippzovq6/ j+tg 9 5+oyy oon. At what point is it beyond the pull of Ear f+ozoyp0i 9/+q65vyjtp 9gpzth's gravity?

  Suppose a satellite were orbiting the Earth justdd*j*c 0hmuxyo. l 5;q above the surface. What is its centripetal ;y o5mjd0hq* d*c .xulacceleration?

  A hypothetical planet has a mass of halz-ls2z)1c sahf 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, czszas)h 2 l1-the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. Tp+1s p8k*q( gr d1oodzhe rad(rdook *s 8zg+1pq p1dius of the Moon is 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 has twice the radius of kqmgs14 wmx)x6po)e: planet A. If planet A has mass m, what is tg) :oqk 4e6x)smxw1pmhe mass of planet B?

  Two planets have the same s cv4lxx (;u,t7- nudzpurface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is tp-nz x47 ;v dxucu(t,lhe radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a spheriw21e( v 0d mgx:s30zbbrl:zvo cal planet (mass M). Which expression gives this satellite's orbital velocity?2( g1do s00lmvwzveb:x:3zbr

  Satellite A has twice the mass of kwv: +by;ln/ psatellite B, and rotates in the same orbit. Compare the two bv /y +l:w;npksatellite's speeds.

  A person is standing on a scale in an elevator accelerating t+k3gzij -erb(, d 8jcv1h6s wdownward. Compare the reading on the scale to the v c8 g(s 6krbwj1 z,tj3iehd-+person's true weight.

  Who was the first person to realize that the planets move in elliptical paths a3,w nurn1.gyjrr,ynj nuwg1.3 ound the Sun?

  The speed of Halley's Comet, while traveling inmiz4 ,fcua* *6m6 qh7ut/eu qs its elliptical orbit around the S/m7hqu4f,6s iqc z6t u*aue *mun,

  Let the average orbital radius of a planet be R. Let the orbi;uq7ncskj 4) tji4 kxv(*lp/stal period be T. What quantity is constant for all planets orbiikvku qjnt7x;4 *sjsc4/( )pl ting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeq +-uqp6qk b*-xe re4bda, with the same orbital e4 bqbq6+-* u-ekpqx rdiameter 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 Earth6eqibn8v*xd 2 o(0 r/rry9cs g to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average vy os(rin 2r* cgbx0qe/896rddistance from the Sun?

State Kepler's laws.2mum:3wug m o7m80r - bwd:eme

  List the four fundamental 7.fqc+w ;a ko; rymyt6forces in nature.

  An object moves with (r13syrpk u m t(j7/cta constant speed of 30 m/s on a circular track of radius 150 m. pc7y3(s /rtkt 1jum( r What is the acceleration of the object?

  The maximum speed aroun/mb o:j7v1 jqe f+w ne;y,oxdhha0q*(d a level curve is 30.0 km/h. What is the maximum speed around a curve witheqxwab;oe m+q /1h,j7:y(jo vn0h*fd twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the pe(::qf r:itp q5yvd7 nmrimeter of a bicycle wheel of diameter q :(75qt:yv rifdmn:p70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s g. ;7zgs8dtmc is located 0.200 m from the axis. What is the centg7.8d czsgm;t ripetal acceleration?

  How many revolutions pn47jat 5nd pkn8d/y0 per minute must a circular, rotating space station of radius 1000 m rotate to produce an 4 jn57a/0dpkyp nd8tnartificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes amnih.x0;c +irround a 13.7 m radius turn at 96.5 km/h. What is the centripe.+; ximhr0i nctal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The sw ,zn 5j5,ealgvqexb; dd*wd/.(f cf4ystem 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 tqg/n *;l,dxz5c (4bwf, de efajw.v5dhe string is not to break?

  A stone, of mass m, is attached to a strong string and whirled cktlmg,m2-4 oq9h g6n 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 at this point is cq-mlt62h, gk9nmo 4 ggiven by

  A stone, of mass m, is attached to a strong string and whirled in a vertiu+ 87srr1nfq;:dmyz ecal circle of radius r. At the exact bottom of7 zerm u1nf+;r q8syd: 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 experienckrdmf(q a7: ma6zlo3btfc:, :es an acceleration of 4g when pulling out of the dive. What isafq :d oatk:6 m7cfr(zm :3lb, the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop pyuld(peaf, * 4u/xu )is beneath him) of radius 3200 mp4 pa/)e uul* yx,ud(f. 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 abouds lg59d /d 2t/zhcj1qt seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of/d ls cq2d1tz9/ gd5hj 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curvetp:xf m9to7p9 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 friction between the car's pxm97t:p9o tf tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed e+ s1pcm.e8 qcof 20 m/s. The centripetal force provided by frice.e8c1cm s+qption is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat ca e mn .h.1i+*d,pe.jegukri;urve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the pj1ei+e ;h r g ,kedina..m.*ucar to make the turn?

  A car is moving with a constant speed v around a lei nrdms0s14 p*vel curve. The coefficient of friction between the tires and the roads*n 4ds1p 0irm 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 bob7 u) vunf-8vb:gz73se jdc0 ulsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignoucb l07 un-8esj f:7v)z3vdug re friction.)

  A horizontal curve od 6,k6zyx5taxx+2lovz0 l; oen a 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, bankedutbm9la:ks8l. ryk ,. at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i w* wzmzwz:l90s 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 k3q : vm2ywlz2x+b.xfa string is revolving uniformly in a horizontal circle ofkm.+ l x:ybf2xzvq23w 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 cf wzkk l;v*2:yar 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 bv2 :fkl*zkyw ;lanks)
(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 of mass ga+*wh31hhva 6 o3x fn$1.67 \times 10^{-27} \; kg$ 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 persolb zxa0p1at5.dv -rd3rr13la n standing on the Earth, due to the Moon? The m3rb-r03. l zd1tald va1xpr5aass 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. If3w aaggp:g-t * the masses are moved to half of their initial distance, what is th g*pg3-:tg awae gravitational attractive force?

  For a spacecraft going from then0 swwb t 9(5c jh8abzy7pgemn)):jj 4 Earth toward the Sun, at what distance from the Earth will the gravitational f:sy9gj cb4h7p0mjznn) (eawb5)8jwt orces 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 is 3b; b w8hg7pqtd gu tyy*6x42)ymx5zh $7.4 \times 10^{22} \; kg$ 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 distancek faevmgs03aaeupb/u 3g/27 + above the Earth equal to the radius of the Earth. What iea+ aak2p 3 g30v suu/mebg7/fs her acceleration due to gravity?

  The radius of the Earth is R. At what disto4(wk xzk84qe ance above the Earth's surface will the acce4o qk48wk(xz eleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above i4:+j cwve.mda c*hc 7fts surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared t+ :a c*hj.4dcmvewc7fo the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleratiotrh(.0 48kpq+af.s l.nnvzy4/ qfaypn of gravity8yq. zq 4kvnans(hf /lyp+t .fa4r0.p 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 surface of the Earth. Thd gc2 yz96qmd2(wrup:/8ru nz e Earth has radius r. If the objecmn duzy/6wqdzu(p2c r:28 g9 rt 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 person change when he goes from .xorx2):t:xrki g :gtsea level to an altitude of 5000 m? (Thg.k:oxgrrtx :: i2xt)e mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is ap70re vt3u:,ppd p r4vt a point 3r above the Earth's surface. What is the satellite's w 7,drpvp 4:rtpevup30eight?

  A spherically symmetric planet has four times the Earth's mass an/sxxjtz 11(9jq mh dl2d 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 thiszsdjl9q m1hxj1 /2(tx planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie oad*68r sn k ini(w2ge/n the same line, with the Earth between n*rk6(i2dw8/ gais e nthe 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 w:qc 2nzwbhspxb ;.jp6 c 41l4to 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 abo27 lnol5pnog.ut the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (Theog2 ll .75opnn mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about er6q0mo c: .na9pg+r8fhxa0pthe Earth (i.e., it just skims the surface of tam xa8 e 9nrfhogrp.+:0c0 6qphe Earth). 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 tih1*-cq.m zz3xtm4dk i6,bawhe Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the Eamkz-h a3w b46. ,*t q1zixdmicrth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, haawfx+a (tgj43cql;1 vkpu4rk h)0ds0d(r5vr s an orbital 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 s ;ws;qw qhgd8xo*jw(,j.*kj Jupiter 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 in nearly circular orbits. Moon A ha s)7vhp*xurm p20 7okbs orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to 7pou s*phv7x k0m)2rbcomplete an orbit?

  The planet Jupiter is aw( r,w 4b1uxt$7.78 \times 10^{11} \; m$ 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 isjvy/1pkr xcj) 2d)drsq xj. 9; the average distance from Jupiter to the Sun? (The distance from the 2.)dkcr1jx x;rqd v )p/sy9jjEarth to the Sun is $1.5 \times 10^{11} \; m$.)