Is it possible for an object moving with a constant speed to accele kh78 hzg,)fl*bac;ag rate? Explaik zag * ch7hg;)ablf8,n.

  Consider a particle moving with constant speed such that iqze2q5 +g h,jxts acceleration of constant magnitude is always peq jhz5+qxe ,2grpendicular to its velocity.

  An object moves in a circular pathrt8(72 aeaxm;j htueuc;yjx*d r*) .e at a constant speed. Compare the direction ofc uer jre;ex7xa *)tuh2 mj;* yta.d(8 the object's velocity and acceleration vectors.

  When an object experience-)qi pbu +ct)/eumla8s uniform circular motion, the direction of the acceler)p/u et+a) mlb8- cquiation is

  Consider a particle moving2:ou if+i l:yg with constant speed such that its acceleration of consful yoi :g:2i+tant magnitude is always perpendicular to its velocity.

  What type of accelera-fbus56qqa,q tion does an object moving with constant speed in a circular qus5b afq q,6-path experience?

  What force is needed to make an object move in a circletfp5:7w 2kn 7uhsz 82aasby(e?

  When an object experiences uniform circular motion, the directiolw 6 hsg y.20k.gno3mkn of the net force i gk 0smynoh.k3 .w62lgs

  A roller coaster car is on a track that forms a circular loop vv+uasg( 3j5ou(d-uw 2i:is hin 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 accw2vo(5 su 3+h ud(j-iagusi: veleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular lo jors/nn7ndhc: i771oop (radius = r) in the vertical plane. If the car is to just maintain contact with the n:cojo 7h177srdn in/track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive js b24;k/duu,g6e 2tl :g +n4bpg/lb cnlb3zethen follows a semi-circular arc until it is going straight,bg/ebus:ld 6c ;2ngp4+et2l ug njb4 /3bzkl 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 radp+9 9ziyi0v gaius $r$ 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 gnqyex: r7qy vz3-)-w ioes 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 tieq:iq3zn-x-yv7rw )y me, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it goes aroun0 iwjo4pl(wop12zc i: 28tw wyd 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 the firsc 0wt:iwwp284 i (2 oolzyp1wjt?

  A car of mass m goes around a banked curve of radiu0wnc k50i y-2izdir;b q f+-k:u woyf8s r with speed v. If the road is frictionless due to ice, the+idwb r uw;qky-f0o8k-: icyi05 f2zn 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 bankedytprr -,3 re8nk4 g8*wtfq:bd at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run)*gek rftp:3,r n48bwy -q8drt for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not const7n5sf **mhj fqpshv z ,(k7:v yt3p1pqant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out of the tukv1jv,f 5 qpm y:zsft sp7*ph q(n3*h7rn. Why do they do this?

  Is it possible for an object moving around a circular path to hav6 6 pgrc;.a:tuq+6nfwv6g5: c aysl fye both centripetal and tangential acceleratioq 6656ns .pg ;:a:6 ayr ytl+wvcfgfcun?

  The gravitational force between two objects is prop/)gon iqv3f68 fpckxsxq;:6wortional to

  The gravitational force betw 4 fvvg)+s-sd-act0zceen two objects is inversely proportional to

  Two objects attract each other gravitationalll5g /xg0lbqu g qp l.8fpr+k8(y. If the distance between their centers is cut in half, the gravitationalq. bf/ppg5 xk 0r8ulq(glg +l8 force

  Two objects, with mas7xc,kx69brh s ses $m_{1}$ 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 majlf,4e/g:ljd- sms- b. 9gzdg sses $m_{1}$ 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 uni 0pff/ee h zt0cizsai 7(vc0d1d.5t0 dversal gravitation.

  Compared to its mass on the Earth, the mass of an object mxc g /n4zhb7g g:8jz0on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is ,)bdwg f33 tquke(qe:yg)l+ djwx c (5on Earth. An object bq),x eyw+cqg d tu(jfg( 35l3dk :)weof mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the i-l+ka s .c2wurocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond t2pk sdh86 :,qi s-gcr:n. awephe pull of Earth's gravity?-rs aqpnsdhp2 ::eck i.g,w68

  Suppose a satellite were orbiting the Ear qxga5hlbl j6po .-+dlb.* lt,7(c pyxth just above the surface. What is its centripetal acceleration *tcj.+b h, l75o6 ygdpb(qlp-xlalx.?

  A hypothetical planet has a mass of half that of the Earth and a ra: -ky;9qek zihdius of twice q;y:z ih-e kk9that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth1 f1yw o(l ;c/c5ffb5o* flmyl:jd;wi. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the ;5l*;(c dcfowfyijbo : mlylw/1f51fEarth's?

  Two planets have the same surface gravity, but plane jvgge/s*8 e2f2u;lypt B has twice the radius of planet A. If pllsgp8 * f/v;ye2jgu 2eanet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but plan,j)ls oi-cf.u7tl. h i8bt3gket B has twice the mass of planet A. If planet A h ksi3ij-ho .ct lul,7)8f.tbgas radius r, what is the radius of planet B?

  Consider a small satellite moving in ae5 wh/+ lgv.s*ssb n6 kty1-nv circular orbit (radius r) about a spherical planet (mass M). Which expres -t6y+hg5n nwb.ekv ss/v1 l*ssion gives this satellite's orbital velocity?

  Satellite A has twice th -/gitr /wrp w7b*r2xye mass of satellite B, and rotates in the same orbit. Compare the two satelliteg r2wt xywr*ib /7/rp-'s speeds.

  A person is standing on a scale in an elevator accelerating downward.eoej4y.my5n r f p)4;jx :ob0y Compare the reading on the scale to the per0xyfeb y4 4);n5y:ojme. pojrson's true weight.

  Who was the first person to realize that the planets move in elliptical paths arf, rp*w)jthiz90 h5nl ound theil nf0rh59 tw *z,ph)j Sun?

  The speed of Halley's Comet, while traveling in its el0m65 eol n3uymykn+ )pliptical orbit around the lmn0k5)yo 3up6nm ye+ Sun,

  Let the average orbital radius of a planet be R. Let the orbitap-3ti u2z (xjal period be T. What quantity is con3(u2ati-j x pzstant for all planets orbiting the Sun?

  A planet is discovered to orbi((ndd)kde(o +:. fgk av pa1:q ,tuxgjt around a star in the galaxy Andromeda, with the same okven ao(xgg ).,jt dkpq(d1f(:a+du :rbital 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 es8egm*ku+v- vr5vprs7dotlj ; /,:qthe Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the aster *-glo5 ve/pvtdvskmqe , 8r;+u:sj7roid's average distance from the Sun?

State Kepler's laws. btnigo0 *8 -wkw+3vhc vpax3:2xw-by

  List the four fundamental forcm*t2vyc7hl 5w es in nature.

  An object moves with a constant speozuc12w/u+ ,p pyq1tf. d 09eabvdo x(ed of 30 m/s on a circular track of radius 150 m. What is the acceleration of thuq y ,1d0.v 2t1eocbf (/9aozpdxuwp+e object?

  The maximum speed around a lev4qxbf 7c;)o v;0o6l .wjscrovel curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius?s j;wooqrv)xb4 lcv c;o60f.7 (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on tt8cg6 8n4 d tafmofk7)he perimeter of a bicycle wheel of diameter 70 c6)mtkn8o8f tagdf74cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating fgu rh:3-0jytat 5.00 rev/s is located 0.200 m from the axis. What is the centripetal acceleratihuf t3jy:gr0- on?

  How many revolutions per min)yu wh:i ov p 0xb6we1;2yyg)fute must a circular, rotating space station of radius 1000 m rotate to produce an arti y)f oe6u yvhw:xgp1b ;)iyw02ficial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes aroun ir)o;:kcqd9 hn/ nm.rd a 13.7 m radius turn at 96.5 km/h. What is 9 dr;k mhonr)/qi: n.cthe centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end ),b2 nd*jn-xbykcohc-vm4yj-mh; l, of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the m-c mco y--dn)4vh2b;hy bjjnm ,*x,l kaximum 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 vxuxt cx3wo(0b7je2gw (;qv s ,ertical circle of radius r. At the exact top of the path the tension in thewx,x(j 3qeug0cvo;( x sw b72t 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 inuze:kk71ttgcb h7r.sm-m g(: 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'ss t1mkz7 c-gb (kr.7m:uh:gte speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of uoma /3qku*r) 4g when pulling out of the dive. What is the radius of curvature of the loop rq* k/a )uo3umin which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of 8e-n9uh1cj qnfv)kp/ the loop is beneath him) of c/jh18 -f9)n keqnvpuradius 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 iszf2k1o 3 wwh:yf -gg/o about seven times his weight. What is the minimumfgo:-3hw/ 1f2 kgyozw radius of curvature 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 awe ,-kw9o:8jjy nq b+ln 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 ml,y8w+oqk:w jneb j9 -? (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 wix /8d( bj:unukth a speed of 20 m/s. The centripetal force provided by frict 8u(x u/nb:djkion 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. W9/mgt api/ uk)hat must be the minimum coefficient of fricti9/m/p i)kta guon between the tires and the road for the car to make the turn?

  A car is moving with a n lks*1 aht2p1constant speed v around a level curve. The coefficient of friction between t1al *21tsnpkhhe 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 Olwvs7.jf- gj8gv2hy- zympic bobsled to negotiate a 100-m radius turn at 35 m/s without skiddi8wsg7y2fzgj jh-vv-. ng? (Ignore friction.)

  A horizontal curve on a bobsled run is bank4o 4qs,8z9zdfm3 nkk red 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, w-;a8lu( foamjee yg1c,;l 0d banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is cpl6 x* ,4b-xdjms7sibanked 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 stris m.+5rjrn.wv2xym 7 -i blb0wng is revolving uniformly in a horizontal circle of radius 0.500mb2 msr- i. rbwyn. v7+5xjl0w
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 car9e tvt- jx9ay+ncikz49m++d c accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 mn i+9e9dm+cxy+v jzc9 4ktt-a. (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 pro6yfkj3j)(olwq t5 i hs5sb./p ton 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 stand ey4.igqvl9+ ring on the Earth, due to the Moon? The mass of tiy r9qgl+v. 4ehe 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 m02bo2e 9vi0yftsq dh) /pma9- k.u llis F. If the masses are moved to half of their initial distance, what is the gravitational attractive force?u2lsi k0o y.b-) qdvt0/2mm9 ph9eafl

  For a spacecraft going from the Earth toward the Sun, at what dnpjj3xb47izs ,dz hg v2/w87nbpl5 b3istance from the Earth will the gdpvb j7g3x7bz 8npzjh 5 n/,wl34 sib2ravitational 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 is x//u- rz./ dh( jhepwm$7.4 \times 10^{22} \; kg$ 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 g: +k.4, xq 8eelb)stdk9zagwabove the Earth equal to the radius of the Earth. Wh )4z8qs.kb 9+w:xa dlget ,gkeat is her acceleration due to gravity?

  The radius of the Earth is R. At what distance abovo befv/sx1r1+e the Earth's surface will the ac+bo v 1f1s/xerceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal gtyxu,5 .pa /uo0cb-zto 3 times the radius of Mars. The acceleration of gravity of the satellite, asauz. c5t pyo0-ub,x g/ compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration ofph1ivc b)z3 1eot)tc( gravity is) c)ch(p1oi1 v tz3etb $32 \; m/s^2$. 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. The Earth hyv bm*gsnn9.2+ :kaz das radius r. If the object is raised to a height of 3r above the Earth's :ay*s.mn2zb g+n9dk vsurface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goeaeu3sz-nab0uuw e(bt*, i) 6rv(v 7 sgs from sea level to an altitude of 5000 m? (The mean radius of the Ear gu6 ersubtsz 3ib)0awvn- *(7 vue(a,th is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r a (1dbu 76bp 1fwhjmxwza2zz j2 :89merbove the Earth's m1drf u:z71p22xbm( b9jw8 ewhj z6azsurface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's (,+. 3fp1xysx6 dl k mpk5ldtjmass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the El3+l1xpk k yj5ftm(d xpsd6 ,.arth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same line,p/3 f ap2ym u(dr*ouf (lod6*i with the Earth between the Moon and the Sun. To3mp*p(f6y(oi a*l u/d2 rfudhe 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*v xziewo)im+ q n1.y)he 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 , vrhh2x*dy 2ult-4nr6kpv6 x0yrbr3 just skims the surface of the Earth). What is the speed of the satellite? (The mh 2vr4ryxd nr 6,vk30h*yrp 2lt b6xu-ean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e.,t31 o: zkr2: 3k 7uaffdxb pqcz2sv5 (jrgcm65 it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The me(5r 7f:d3uozgc6r1mv ktb2 5fz japxkq:32cs an radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the sagw:a4l8 *n*o)e(7 g fsz mgiiurface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean raa4ms( in8zf7) igea :g ol*wg*dius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital ,x16xpg2h7 a y(lrduzdiameter 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 o*mcgof;beb (,7kk j.sq*og:gsf ,t /yrbits 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 has orbital rv))m )dfx/ ja9qjam1iadius r, and moon B has or)q9f mj))/i m1daavxj bital 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 isf5 wff h6viap7/zc l)fff/90 b $7.78 \times 10^{11} \; m$ 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. Wh6r i*p( 0lbrqx5stp8kat is the average distance from Jupiter to the Sun? (The distance from the Earth to the Slb* rk qri6(08xs5pt pun is $1.5 \times 10^{11} \; m$.)