Is it possible for an object moving with a constant s*im dk .wp;d+ :*jukexpeed to accelerate? Explain.pmdu* x ikkj+w.*ed;:

  Consider a particle moving with constant speed such thatmpn ur5eb22r:bqal d.tlc:x of cv8 + p3t;+6h its acceleration of constant magnitude i+6m uv:r2t3en b2 :+pf.5p dl;8cxhblcrtoa q s always perpendicular to its velocity.

  An object moves in a circular)fb/ enhwi :m. path at a constant speed. Compare the direction of the object's velocity and acceleration veceimw.f:) bn/htors.

  When an object experiences uniform circular motion, the dirtjhds mvnv jbv,6i0/)if w;ob /3g 8h;ection of the accelerah /) m0;b8g3swvn;fh tjj/vibo6d i,vtion is

  Consider a particle moving with constaq:s r+j7d4o5rg*tcd k79t8kcw/kurh nt speed such that its acceleration of constant magnitude is always perpendicu+ tr78:qrwrd*kj chgod5su 7c4 k9k/t lar to its velocity.

  What type of acceleration does an object moaik7)qb 28gx xving with constant speed in a circular pa biqagxk8) x27th experience?

  What force is needed to make an object move in a c sfv/j :iw8k /mwudsuha7w:9+ircle?

  When an object experiences uniform circular motion9 yk0r lpust;5, the direction of the net force r5sk0l9pu; ty is

  A roller coaster car is on a track that formr s2 m:d3qejyv3v-bq 4uc-eg4s a circular loop in the vertical plane. If the car is to just maintain contact with track at the temve3vsu3-4g-qc y2dj:rbq 4op 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 (radiusu+anhup4 . tq6 = 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 aun6 qhp+. ut4minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-g 4byxqkf ,rftd:qt-i8;s i+7oxz)7 kh79 je dcircular arc until it is goingdj97 xryko;s4fdqth g 7:8q)ebtx z i,f-i+k7 straight 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 (tuw7 f 4ngu4/4k9k jaq 4btejradius $r$ 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 tlnapp55u m.rb:v5v 3at 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 secondlp.5 vvbn:r t5ap3um5 time, compared to the first time?

  A car goes around a curve of radius r at acwq*g zm2ja02m/zx 4q constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on them 2cwz2jm*04x qzagq/ 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 vtksm 6j o(rxjvvse:2ue 7.r1+. If the road is fricrv1 j:se7 2(xksvto6u+mejr . tionless 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 equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, 7e( eg5q5ar hsbut one has twice the radius of the other. The safe speq7esr(5 g5 haeed (no friction needed 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 on the Olympic bobsled trackf+vtqh4lfzj a) 6cq. 2 is not constant, 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 turn. Why do th24z)qqca jv6thl+.f f ey do this?

  Is it possible for an object m; 8bxb ae l0/mgkcf3(ioving around a circular path to have both centripetal and e ik(acx0m bb;l3g8f/tangential acceleration?

  The gravitational force between two objectslj*i + v mkhp 4uk/b.*t3lm8tf is proportional to

  The gravitational force)q*e wp.- 2uasdxr:z q between two objects is inversely proportional to

  Two objects attract each other gravitationally. If the distan bj2( ugg20ud,k:ntm ifn8g*+sbvjh, ce between their centers is cutbm*t+ uj2nvsjgn(,ub ggi 0:2hf8d,k in half, the gravitational force

  Two objects, with ma1 0mpn nm; 5jtz+ (pi/vpsol+wsses $m_{1}$ 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 maswt ebd9kqiqgd(m )6 u b/7h,1oses $m_{1}$ 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 univeq7k96m oovl t-rsal gravitation.

  Compared to its mass on the Earth, the mass of an object on the Moon is.in*53qj0hu *vhn yw vrer / *eja.fl)

  The acceleration of gravi2sje u+:np/.p22lhoqr/ aiy t aw5 ukj m/+vo(ty on the Moon is one-sixth what it is on Earth. An object of mass i k2oouj:t+ a2lujsvpny+r am5/ qp/ewh2.(/
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's weight oma.h5 ktz6u6

  A spaceship is traveling to t5sq) sj vgb2y;he Moon. At what point is it beyond the pull of Earthjs ;ys52g )qvb's gravity?

  Suppose a satellite were orbiting xcdpn z.18 8zythe Earth just above the surface. What is its centripetal accelez8p8.ncxyzd1 ration?

  A hypothetical planet has a mass of half that of the E,0 cst4:wawab4wu/98c .d - o rwiwurqrbfq*;arth and a radius of twice that of the Earth. What is th4icd:8obabsw9cufawu w. *0qw/q r, ;w-trr4 e 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 Earth.yxu k 9 4q9sz6xi,a0:hgj8hw y The radius of the Moon is one-fourth that of the Earth.0qgzjihy:9ah ,x6 wy xk89us4 What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity,r6v 6u4jbiz b: but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of pbz6j 6:uv4brilanet B?

  Two planets have the same surface grqgcc o-714kx5uxb.qux ir4x6 avity, but planet B has twice the mass of planet A. uobc5x-k 1q.x xqi46cx 74urg If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a ev5( a4ges9oot2m6( 4nri tbbspherical planet (mass M). Which expression gives this satellite's orbital velocito6t4 nevgs(a 9(bro4eimtb25y?

  Satellite A has twice the mass of saa9vj6,klt)d : ,cr glotellite B, and rotates in the same orbit. Como, cgkd9tvr6 )llj:,apare the two satellite's speeds.

  A person is standing on a scale in an elevatorop+0z47p wn* kjsbf+d 1voc 0v accelerating downward. Compare the reading on the scale to the pervvzdnc4o*k7 fp+s po0 jbw 10+son's true weight.

  Who was the first person to realize that t 0 qnt(2s3amsshe planets move in elliptical paths arouns(sq03mas nt 2d the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around thi .8gt6kelszski2 lr0349 jwwe Su8ks 6wwkli9itr4s e j3 z2g.l0n,

  Let the average orbital radius of a planet be R. Letl3x6oa. 5gpk d the orbital period be T. Wha5lp 6dxgo3 k.at quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around n sx0v i+qt/k.:noin/a star in the galaxy Andromeda, with the same on x:qon/ +i0/n v.tksirbital 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 Earcekn; .0ueyx. th to the Sun is defined as one "astronomical unit" (AU). ye0. ;x.neuck 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.k ( ufr1m(o5td*,hqf ;bkk5og

  List the four fundamental forces i3es qh2ma: s;/an)fvw n nature.

  An object moves with a)uq5 bro /b)qg,q6me j constant speed of 30 m/s on a circular track of radius 150 m. What is the acceleration)5)oq, murg j/6 bebqq of the object?

  The maximum speed around a level curve is 30.0 km/h. What is tg 7lmy+)/2 o:nivl xl i8rw7nw:bkzc;he maximum speed around a curve with twice the radius? (Assume all other factors remain unw m: 7+2:lcgnzx y/8nkv lrbi)7w;iolchanged.)

  What is the centripetal acceleration of a point on the pe hk-ggtl n2q (*8tprp3rimeter of a bicycle wheel of diameter 70 cm when thepqg3gl8 knt *h -prt(2 bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0 xk ,fpu.0m(ii.200 m from the axis. What is the centripetkim xf,(i0 p.ual acceleration?

  How many revolutions per minwssy0 if/afg k: 3lk(c.ik(p6ute must a circular, rotating space station of radius 1000 m rotate to produce an artificial gragcsp/(lkisikf a0. ( f6wy:3kvity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It gkc+- py/1 faej0umvx):m esrg.x2e8h oes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on )ymkjeh-r xx 8mf1:/.+egva0e 2ps c uthe motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string.nvwh h m5 7qb2kx2-8ec The system is whirled in a horizontal circular path. If the maximumkn58 7wbvq2cx h2he -m tension that the string can withstand 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 a7/ ci (agx/ 1aym5menin a vertical circle of radius r. At the exact top of the path x(nm/5e1y gc/aaam7 ithe 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 *,)bp(l9* hd j)t ,gzzf9wfoy9 ljrarwy,8avto a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the wraa,*9ry ) glyzovpzljf)dj t, (b9wh8 *,9fstring is 3 times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceltg 3/h bsp-r;c: ( qc 2t+cyocp7g+zpxeration of 4g when pulling out of the dive. What is-xhyb;t7 qtpgppccc zr+/3 2+s(:cog the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical l0pigzqr0yj7w.2h; bvy i8 :-eoibv .loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he 2; yi. yl0q78i v.ohjz:grvw-0pbie bis pushing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilem0;/otr1 iddl2i ( u,py.uajot can stand is about seven times his weight. What is the minimum radius of curvature that a jet .ut0i2;1y dapirl jmde/, ou(plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s ro,pl/s8 i+(z2mo rftmb9v:wo (xq scj)unds an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can thilm,it +rvcq9jz bfw2: o(8sp)sm/x(os 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 (n;y. xo2o12spnqvo9z pf gw 050 m with a speed of 20 m/s. The centripetal for2oon w0pg 2ps.9y xfnq1z;v(oce 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 radius 50 m at a speewcqyu mz* d g;u0;z0q8d of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for theuuqmz8;g;*dq0c0 z wy car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefficonc,rwaffb luj7)yx 20k 07-6 b2 yxzjient of friction between the tires and the road is 0.40. What is the minimum radiusyx7o l-)z 27fj a n2cyfj x0u,bw60bkr of the curve if the car is to stay on the road?

  What minimum banking an, la-xt,y/z)wu my,y hgle is required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictiyxyut,)mh ,a- ,z/lywon.)

  A horizontal curve on a bow85p/t ,)ytutb/ jpmqbsled 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, a +pbry5x wt,cp.j 74cbanked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is btzl (7gheule ,bn9o89anked 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 zkwg**dq3-aj lsw.j 4in a horizontal circl lwj*dgzj s4kq-a*.3 we 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 unig8:vayvi3zd (x(th7 wt-rpy+form rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical val87d(v pa+ztixyyhv -(:3g wtrue 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 of caf.3kn-+kq(d ltg- fmass $1.67 \times 10^{-27} \; kg$ 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 onxoef o .zwa)6 wk6vw6g)2ou5*ip h7ms a 70-kg person standing on the Earth, due to the Moon? The mass of the Moon ia pf) g6z*75w)o6wmk6 2.xsv ioouw ehs $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force betweent)a4a5w6lm uzv. akt; two masses is F. If the masses are moved to half of their initiaal6mktaauwzt5 4;v .) l distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from : orl .xk/icp- jac/ricqj. qi+2w-w(the E-al -cq (r:iw. jr kj+/i./iwpccxq2oarth 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 . +hq )n -1czc1,gwn9hajaflfis $7.4 \times 10^{22} \; kg$ 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 gigmifel((e/ srf,7)3e gz .n"space-walk" at a distance above the Earth equal to the radius of the Earth. What is her acgergfm.3l 7,z/ gf(i )e s(ienceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's s* a 9c1x 6hg pqev*28:frt6q-h6u 6mgpojo kmkurface will the acceler p6u:-6 cm hopm9q 6 *fh6j28*r1vo etgakxkgqation of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a x mn5noo(rjm y83)w/:pko hj/distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to 3pm(n:o hoj5o x/r)y8k/j wnm the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's ceo/5dr(xkh.os asu0;nn 4:u fj nter, the acceleration of gravity un:s(;/fr.ud5 ho ox4k0njsa 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. The Earth has radiusk:eyy zbz87(aagg2 5u r. If the object72yyz:u akg b5ze(8ga 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 m t,a t20o;qoc e,wla2sea level to an altitude of 5000 l 2oate;q,w 2moat,0cm? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r aboveuu5d ;cbt16(qrdgg4fu jl ..p the Earth's surface. What is the sateupr4( jd1bt d.g ul ;fgu56q.cllite's weight?

  A spherically symmetric planet has four time2j 3oko zhy2j)s the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth,)z3kojj h22oy how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Et+.me2fil,bh h , 88kcrgb3 ftarth, and Sun all lie on the same line, with the Earth be 8,tlg.ebfck+bm2th3f h8r,i tween 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 i15:gux. (elf+sssq6cxmpu3p s transported 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 )ga d 8hws9m5mjust skims the surface of the Earth). What is the speed of the satellite? (The mean radius) dhs5m9mw a8g of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just skim:)vm;f d4oewi t wl3hm0nsn z, (ea)p8s the surface of the Earth). How long does it take to make one revo8f3)pm wle,(;oht zmia 0n)d4:ve wsnlution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 4-glag9ij cl:230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (Thilj-ag: 94l gce mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbhzwfo9,gk+/,9n6c bsv3 yz y mital 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 Jupiter orbits the le qapydr7 d 4:1 hpdf-qdc,goz173s 5planet 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 bzcej;w12vt.c .v9pi in nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius vt1iz .ejc.2wbpv c9; 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter iswusaceth2 jy-0 js q5; j6uz+: $7.78 \times 10^{11} \; m$ 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 ak m2qx ns,h)6vy5myd9i29mtl+- tmg wverage distance from Jupit26wmxtmi2 ynqvymd9gl95,+mt- ks)h er to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)