Is it possible for an objectf.,ndr ,vlpwcu z);3c moving with a constant speed to accelerate? Explain.3r.cw, up cv df),z;ln

  Consider a particle moving with constant speed such that its accwnvo l/v+ xg j6xvoxbc7 l*94(eleration of constant magnitude is alx*lol 6 xg ovvb9/x(w+v4cn7j ways perpendicular to its velocity.

  An object moves in a1 lebn047 qhmr circular path at a constant speed. Compare the direction of the object's velocin e10hqm74lb rty and acceleration vectors.

  When an object experiences uniformk )mt+ rgqip:/a4-cvd circular motion, the direction of the accelerationd+q-pg i4rk)vtcma: / is

  Consider a particle moving with constant speed such thatjji577 fpsl7z cm8+d 1t/ tihu its acceleration of constantld/8tiz+jsujh715 mpi 7t 7 cf magnitude is always perpendicular to its velocity.

  What type of acceleration does an object movw-zdbw8l: fgquv/ aylt3k6-vnr 1( e *ing with constant speed in a circular path exper d u/v(w1l 6f-k-vyalz*n8:grtbeq 3wience?

  What force is needed to make an object d)jjcyft1shg-45ms5o :q k,zmove in a circle?

  When an object experiences uniform circular motion, the direction of the*ob-as5cm8 si net force i i m5s8sb-*oacs

  A roller coaster car is on a track that forms a circuyryhvc jk+ u7 et 6)f(lb,ox3/lar loop in 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 centripeta3/(tuxlk,j y vefy)cr+b oh67l acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circularyu9 kuu,1yi17(bk5y satq8t u 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 i1qu kayytiu1uk ty ,59sb8u 7(s the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-cxs;+ t.vk9 +rb zht3zyircular arc until it is going straight up. Just as the plane is at its lowest point, tz3b9yz; .rktshxv++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 vq40 /ds*dl ekof radius $r$ 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 :,zemwe ,xlf):ki z9jconstant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal forcezz xj:mfi:e9lkw ),,e 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 speedrmlglz,os2 z9: zh(xba:( 3tq v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as lh,a(gt:39mzz (q : xrs2zl boit goes around the second curve, compared to the first?

  A car of mass m goes0uhc .rjs r.z. around a banked curve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate thzshur r.c .j.0e curve if the horizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curveseyokqmvm kw7w83v:- 8 on a bobsled run 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 the smaller radius curve is v. vkq 37ymwkev8 wom8 -: What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track i ynp) xss80q9rs not constant, but increases upward from the horizontal. Coming around a turn, the bobsled q90pyxsn r8 )steam will intentionally "climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object moving around a circular path to have both centripeontdt ag75g0aa,8b 6ds( e8letal and t7aote0,db 6gt8ea(n58ga sl d angential acceleration?

  The gravitational force between two objectqkr( ucn; s*6.jb0hio s is proportional to

  The gravitational force between two objects is1r(6 gasevl2a udx7r wge 858y inversely proportional to

  Two objects attract each other gravitationally. If tr )w6h*aryaha/9kyp3q k 2ct0 he distance between their centers is cut in ha/k)qpr0w9 3cakh6 ayyhrta2 * lf, the gravitational force

  Two objects, with massesxb7uxs)g 8 ,b gf5m)jq $m_{1}$ 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 masslqxt..7vky *s;exx dmx2 g(+xes $m_{1}$ 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 uni3a /o,f pjl-a q,4(dl+pzkj ahversal gravitation.

  Compared to its mass6hqqrc 81 i+pn on the Earth, the mass of an object on the Moon is

  The acceleration of gravity onyq4a05jn1nxs gq;l y/jk/ * uf the Moon is one-sixth what it is on Earth. An obje/l0s1ky fu4 qng *x;ayqjj/5nct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away fro,ms drndl. ( f2*mpss3m the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At w 2+gd5lf*)pj +gyss2 5o qdahfhat point is it beyond the pull of Earth's grf)ag hdfq+2j2l y5 sg*5sod+ pavity?

  Suppose a satellite were orbiti6reaw ttcos tc,z,5w 0(-f-nkng the Earth just above the surface. What is its cct rsww-n0z, t,ck -65 feota(entripetal acceleration?

  A hypothetical planet has a mass of half that p6nj4 i*e21 ck:rdvl4asfhr/of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the p46lpd1n* evk2:h i rr/4safjclanet 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 jp ebfi +-c-aqpu f:(oqa8kp 8mi1-2y Earth. The radius of the Moon is one-fourth that of the Eapqcj-f8 k pab2 :-(e81ypm i+-iaofuqrth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice7u9s /x0sbgp j the radius of planet A. If planet A has mass m, what is the masx7g0b/s9j u pss of planet B?

  Two planets have theo,*xaa mky3 e ldb(p-3 same surface gravity, but planet B has twice the mass of planet A. If planet A h,aky3 *ed-am3xpb( ol as radius r, what is the radius of planet B?

  Consider a small satellite moving in akgv -z4q2z(gf(ozx g lb2 u//z circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite'o2 zzgg2// (zvfb ug-kx4z l(qs orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in t0x/gs+zrxil( yw mjfvo fh rl;9:o517he same orbit. Compare the two satellit 09y zf: foxowvm+gsrj1/(l x5lh7r ;ie's speeds.

  A person is standing on a scale in an elevator acceleratinc.0 ifqo 3lq-wg downward. Compare the reading on the scale to the person's tl iqw- 3f.0qcorue weight.

  Who was the first person to realize that the planets move in elli,,ngi( zg )suwptical paths around the Suzwsn,,ug g (i)n?

  The speed of Halley's Comet, while tra 7stz :au2uej0veling in its elliptical orbit around the u et0:7 jaus2zSun,

  Let the average orbital radius of a plab-zvz7p-c ,w, im (l1v ap2o0gsb3xzxnet be R. Let the orbital period be T. What quantity is constant for acm 7zzpl- ,gibsvozbwa x2 v-p30 1,(xll planets orbiting the Sun?

  A planet is discovered to orbit around a star in uie3;/:s*of5llaqzk na5 3sj9wj,/2dzt oipthe 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 planet3o :5, s;djw53 9ojlzis*al / i/qnaptu efz2k be, compared to the Earth's orbital period?

  The average distance from the Earth to gc2*9a6ze6g 4 w csvv syi7/jtthe Sun is defined as one "astronomical unit" (AU). An a 9gcs */647 a wgs6j2yivtzvcesteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.j u-/zqq-h 6ix

  List the four fundamental forces ind*p m1h- )(fy.ta-aehv*3ezwi0 sr yd nature.

  An object moves with a constant speed of 30 m/s on a circularg2v tv-sohuxl92 aq/tn*tiy7 vy; /l: track of radius 150 m. What is the acceleration of the object;-2s 9vn/uvyv:y toq tlit*a 7g xlh/2?

  The maximum speed around a level curve isz4bq3ldx., mf 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors rema,fz xd.lm34bqin unchanged.)

  What is the centripetal acceleration of a point oxi esdi/ x-dk 9j4*g0yybg:it 60sf( sn the perimeter of a bicycle wheel of diameter 70 cm when the bike is moving 8. 9 s: *t0sd0iy(f sijdy-keixgg b4x6/0 m/s?

  A point on a wheel rotating at 5.x8/rfadnq90jb z1 tc.00 rev/s is located 0.200 m from the axis. What is the centripetal accelerat8fxa d/n1crq.0t9b jz ion?

  How many revolutions per minut qhmf:fu s)w3d4b-jaf3dfswn24 z0x1e must a circular, rotating space station of radius 1000 m rotate to produce an artificial gravit ufsxzj q 4w ah s3ff1d:wdf2bm)4-3n0y of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn a0i6bj 5 k/7tdpdddx*ht 96.5 km/h. What ibp5 6kji0dd t/7 dhd*xs the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system luiel x/18 2vbis whirled in a horizontal circular path. If thlu1i/ lxev8 2be maximum 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 45a8awawh jk e17 ,ihxand whirled in a vertical circle of radius r. At the exact top 751hwkeai8x4wah ,a j 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 an8*qce gz mhhmo8az 41+d whirled in 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 ha8*+egmhozq41z8cm at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when plqb l;ypdxk.,(0dc90kr cf i9ulling out of the dive. What is the radius of curvature of the loop in which thqk cxy fr0dll9p 0 9;.k,d(cibe plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop is ez,v30znm gy8 af;;bqbeneaa g ; ,z0zyve3mb;nqf8th him) of radius 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 standxdf da/8;cz3 x g9v;yd is about seven times his weight. What is the minimum radius of curvature that a jet 89xvadzgd/dxfy3c ; ;plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s icse(akxu pxc(j ;5 :ux/3u2p rounds an 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 m? (Assume the same coefficient of frick a cps/j e3;u (2xxcu5u(xpi:tion between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a rxn*( n ha)1ccspeed of 20 m/s. The centripetal force provided a(*r n)hncxc1 by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curv3wvm g*z+,m2akfbfm+qh 3 +)ort0 u dae of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the rvak)+bf*qr,ha o03dugz3 mtm f2+ m+woad for the car to make the turn?

  A car is moving with pq/ d g,zt2a9cr/ion3 a constant speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve o2drznq/ct3/ i9 a, gpif the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled ty ,r696o0)wbt u czvzto negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frir6 z)o9t btw,z60yv cuction.)

  A horizontal curve on a bobsled run is banked ygr3v9 a;zcl*a/:g om3s8mniat 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 0 1us4b-;cxf elccx 3hradius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i k m596d8lag k9lkxm/hs 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 horiz-m5hd bs 1tkx 8(yfde)ontal circt8ed-x(fh1kmb ds)5 yle 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 c88g r qqfafn/r*y2p*gar accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a pafy2rq /n* g*8rg8qf 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 a proton of d w39)t :*pa+ ppux9uzr1n;jiu u wq:imass $1.67 \times 10^{-27} \; kg$ 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 m( 3g8mfpyr 0 v8dmy,son3r i9on a 70-kg person standing on the Earth, due to the Moon? The mass of the Mo3 8ridmm 3v 0( myron98fgsy,pon 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 masses areo(n7u (xfjuhyb+n( -y jdp/u . moved to half of thei-o7+n(u up f(by(yjnj./xuhdr initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at whap* tt6 jibzu(sr ll(vcv(jj)rxh+/,- t distance from the Earth will the gravitational forces dueslcxv rtp(6 jtvib)l(j-,(h j*z+/u r 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 Moonfs) a ,cabdqls7 6vt/- is $7.4 \times 10^{22} \; kg$ 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 above the Ea :f y97ogdtqm+rth equal to the radius of the Earth. What ism7g oq9+tf: yd her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Eaz1l :u5tbvws 9rth's surface will the acceleratl :1wz5s9bvu tion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance abovea71dqcg3 x79i(ucr t x its surface equal to 3 times the radius ouxx(g ia7 cc1d 7q39rtf Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the accelx t,q-ldz,wjr.j(a0 m ifw2 ;ueration of gravity is 2zx,rjdli- m0wuj ,f.t ( ;awq$32 \; m/s^2$. 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 Earm(9smqt ro.,x th has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its wtxs.(9 ,oqrmmeight?

  By how many newtons does the weight of a 100-kg person change when he go khhum2ek ,c52es from sea level to an altitude of 5000 m? (The mehe2chkuk 2 ,m5an radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of muxryi8a0vr,l,4 ma l(ass 100 kg is at a point 3r above the Earth's surface. What is the satellite's weight(ai uvl,a rrx 0,lm4y8?

  A spherically symmetric planet has fozkn uf a.2nt59dy:c-zur times the Earth's mass and 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 this planet?f2- nt .zckuaz9ydn5:

  During a lunar eclipse, the Moon, Earth, and Sun all /mx(hy3 wgz,clie on the same line, with the Earth between the Moon and the Sun. The Moon has a mass,w/3x cghym z( 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 transportkig,yzsy cf2 /t6ddre8a l152 ed 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 just skmlx*h5bi:)c jd amqc 4udjq4 3d 5i/n9ims the surface of the Earth). What ij4q5b*ac d/4d:5hcnmq)3xum ji l9id s 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 f. qa rc4ulc6;(i.e., it just skims the surface of the Earth). How long does it take to make one rev 4f luca6qrc.;olution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circ mrxir.65l uo)9okpw6ular orbit 230 km above the surface of the Earth. It is observed to h) 6lp .u5k9r moixro6wave a period 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 Jupitb)hxhhhyo y9a.x8s .ae6d 752k7swzuer, has 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 of6ff8oz 8gcc kz,.zg (g 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 has orbital radiushf-aw.dipq)u hd 5y-) r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it ta)fu.w ap5-yhdh-i)q dke moon B to complete an orbit?

  The planet Jupiter is,lmz c01,id pq2 igz)g $7.78 \times 10^{11} \; m$ 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 toox8,m rdn pg4 d3hc 4i y5wz.8bm3ix.h orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance .4mz,ob 3c8mx nd 3pxyi54rhg .iw hd8from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)