Is it possible for an object moving with a constant speed to accelerate? Expla y*6 o4n 5agd;2qyzd1q te)s r(pc,skhin.4sgcdy eq ;a d1h* skprtn)5z(2y6,oq

  Consider a particle moving with constant speed such that its accelerattg5k . ii9 0fh)i-1eygb2pbk iion of constant magnitude is alwa1) py2.fg0-iekgi9t 5i hibkbys perpendicular to its velocity.

  An object moves in a 6 +pg vw w4s+a/h-uwg9-ukbti circular path at a constant speed. Compare the direction of the objecbs + hkgvwwgw+p6ui-au9t4/-t's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the acc;ycf,btrf * 1z ++6fs0 nrohyceleratio;so+6fz nr y 1f,thbc+*0fyrcn is

  Consider a particle movin4ww 2d,krfvbs we)x1- g with constant speed such that its acceleration of constant magnitu)1w-efd4vrb,s k2ww x de is always perpendicular to its velocity.

  What type of acceleration does an object moving with constant speeh+;:yj t4q vb.ddy u+ad in a circular path exy.v+ 4 yd;+j:qd bhtauperience?

  What force is needed to make an object move in a2fy)6xjqd xwgm1 u 5+zo3oq+h circle?

  When an object experiences uniform cjea,-l phds( /ircular motion, the direction of the net forc(e/pa,js h ld-e is

  A roller coaster car is fhmx)d dm 1 z4zj2dc:k6 bq.9con a track that forms a circular loop in the vertical plan6 )bxd1mc mhj2kdc: q4zzd.f9 e. If the car 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 =gpedt+0yw2 o+u/ s9fii ko3/s 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 valuey+fwk/ igo9ep02 duos3 +is/ t for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc untm ye4f5hc./t95s wcag+z 8ituil it is going straight up. Just as the plane is at its lowest point, ths.w+ 9c m5i8 afc/eutgy hzt54e 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 eh4 ,r/xmaa kv 5a4js*curve of 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 constant speed v. Thw*qa y 0;t)l f8akhxi3en it goes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around ta3t *0x hy)ikafql8w;he curve for the second time, compared to the first time?

  A car goes around a curve of radius r at a constantzepf g he2wc p-2g 6m.wl32g9h speed v. Then it goes around a curve of radius f3-gg el92w6cp2zh e .m hpg2w2r at speed 2v. What is the centripetal 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 radius r with speed v. If tj8ea9z7lk :n .aj7he mhe road is frictionleljem98. :h k7an7ajz ess 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, but one h. p(me bnjq7pvi*.wp *as twice the radius of the other. qe*i(w7bnp.v *jpp.mThe safe speed (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 track is not constant, but i16x v)z cyn9dt(ppn m*a(hq7hncreases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lowez(c9axt6ynqh 1*vpd7n )(p hm r coming out of the turn. Why do they do this?

  Is it possible for an object moving arou*z15rnexp qo* 16rlpcnd a circular path to have both centripetal and tangenol**p 6 z5n1xrpc rqe1tial acceleration?

  The gravitational force between ,n tr 2b3pwxn,yvh*o:two objects is proportional to

  The gravitational force between two c7nf6b/k a.dx objects is inversely proportional to

  Two objects attract each other gravitationally. If the dis)hxn7q f9n o2zqe(ip2 tance between their centers is cut in half, the gravitational f eqf7(pinox nq92h2z) orce

  Two objects, with massesvjng1:a8aqh6ifx x ,0 $m_{1}$ 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 masses s/d4cjl: q1* t3yih.eie b ah,$m_{1}$ 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 universal gravit5f8 ozn ppffu*oab /8,ation.

  Compared to its mass otgkc+apgp,xb 1c.e s,4 w7f t l;--thjn the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Mooj3t6lrx8* ipfn9ol.+maf q f+ .zulv 0n is one-sixth what it is on Earth. An objecj6txfa. *qm fl+i luo0.8+9rzlf3vnp t of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's by ++a67cj mvpsurface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it ghc) p/5 hv(b bbe+,l//rsbdu beyond the pull of Eah ) l/bu(b,rcd/b vs+hepb5/grth's gravity?

  Suppose a satellite were orbiting the Earth just: i3t 3q.bjtff above the surface. What is its cef: b.f3 tq3jtintripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a rarzzwxk503 .(rb(l v ux s6fa)pzt(s/fdius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration ((xx)( lwv0z/r6s3 fpksu. f r 5tzzabdue to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what +uj57y:dy,e b cco uo+it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon'ec 5o7j,ouy yu:dcb++s mass compared to the Earth's?

  Two planets have the same surface gravityv ihv;l.k.i jh*x *3xd, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of plane; v3dil*ix. hvx*j k.ht B?

  Two planets have the same surface gravity, but planet B has twice the mass ojb.bd/mx oq4 )r4rqt)f planet A. If planet A hao4bmb/ t)qx.rj4q r)ds radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (ra /2bf:gupat- gu9sx1 idius r) about a spherical planet (mass M). Which expression gives this p:-fxgi/tg 12bsuu9a satellite's orbital velocity?

  Satellite A has twice the mass gm)x:mpomuh6b0,xam t 9 :vc)of satellite B, and rotates in the same orbit. Comparxbm: v69u:tmh m)pc ma,g)ox0e the two satellite's speeds.

  A person is standing on a scale in an elevator accelerat+x86ww te3s.ltarp6/r hup g 3ing downward. Compare the reawx36h +urs8lpt36t erg.w p/ading on the scale to the person's true weight.

  Who was the first person to realize that the plap1d4:c wbz k ah2wplz)5zrh *7nets move in elliptical paths around thz5 41 r2*bpha)ck wz7hzdw p:le Sun?

  The speed of Halley's Comet, whi n3wsj3a6 yyqt*rk;0nle traveling in its elliptical orbit around the Sun*36ywkanjty0rsq n ;3 ,

  Let the average orbital radius of a planet be R. Let the orbiyhg pp 7lzu4q2*g k,5jtal period be T. What quantity is constant for all planet *,gz4lp jhqu7gy52pks orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromedi67ve+* ,zc27skewmx1hl+ ,fph6 rcfmvpb8aa, with the same orbitalm kw6i*6lr +z2vpvffs,p+ebxcc 7m8 hea7,h 1 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 is4;i8.vdk1y ioaj jj2 a defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Su8jya4 jk1; jdi.vo 2ian?

State Kepler's laws.m4 vtu m37*w.zzk q:vd

  List the four fundamental forces in nature(wywtiv ke.t(ei :h+;dqhw6:.

  An object moves with a constant speed of 30 m/s - u:br.kh h*nion a circular track of radius 150 m. What is the u nh*h.kri: -bacceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What ir,qsu 7 ho rs5,xyp34ks the maximum speed around a curve with twice the radius? (Assume all other facr3k4u , osxsr5hq ,py7tors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bic2on(; f*til 0cmf slt.e6:xkoycle wheel of diameter 70 cm when the biks .2k *fetnfm loxc6;0:lti (oe is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locatedj6h1, b+pgb ,ndu oh6+qv2uh k 0.200 m from the axis. What +ou,d h6bh6gqk jh 2up+b,v 1nis the centripetal acceleration?

  How many revolutions per minute must a circular, rotating space station of radiu tehq- 2895cvizfa4hk s 1000 m rotate to produce an artificial gravity t iqh 9-k8h5c4av2f zeof $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a d8,h yd3m yx*ia4dxd-13.7 m radius turn at 96.5 km/h. What is dxihdy,3- a*y 8xmdd4 the centripetal force on the motorcycle?

  A 0.50-kg mass is attaul : qg0 y*;xkqo5mkm1ched to the end of a 1.0-m string. The system is whirled in a homx*y:omu10 ;k kq5lqgrizontal circular path. If the 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 and whirled in a vertice)r ojy(vc0+f al 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 givenojc(+0r fv)e y by

  A stone, of mass m, is attachedbe9clk97jzbpi 1 ;n f4 to a strong string and 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 at th917b nzf ;kcb 94piljeis point is given by

  A jet plane flying 600 m/s expc8bh6f2i i )k4 8epheieriences an acceleration of 4g when pulling out of the dive. What ip4ik8fb)8c6i eeihh2 s the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the chc 4 26tudjk1lenter of the loop is beneath 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 weightl4thku6d j c12. How fast is he going?

  The maximum force a pilot can stand is about sev;m*wrb(96ibnh i6ifm3 h z+quen times his weight. What is the minimum radius ofz6i9n+mhhiq wr ubb(*6 fi3m; 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 an 80-m radius horizontal curpbq::n17w wpuxo:2b 4a4yn qw q() eamve 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 a:1no xeyq:n:pq q47 )wpwm2bba4u(wcar's tires and each road surface.)

  A car is negotiating pm/n n(pt npb1x.3o) ma flat curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by bopm/mnp(p3 1)nt xn. 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/ fvm2ai*h 8pgfg7)e3 hs. What must be the minimum coefficient of friction between h* fe7vgif mh2)p38agthe tires and the road for the car to make the turn?

  A car is moving with a constan z/lq .s fm64c( wqjla*kjbr6wg09si*t speed v around a level curve. The coefficient of friction between the tires and the4z9w c q (6 j.rqm* fa/*0jwlsikblsg6 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 requiredwa rv/ swc,5;9 loydl/gyi2k3 for an Olympic bobsled to negotiate a 100-m radius tua yw ,3ws;9y rigcd/lvkl2o 5/rn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled r:cw.gvuyn:*0b b9.jg1c8 cux6nyl2l* y j hhcun 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 rady w-;w.u7t;svjv-zt y ius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m iw. 4t)bsfb vw0s 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 ufc2wjh l)+n- dk;*fcmniformly in a horizontal circle2l nkfj+;df*c c)- wmh 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 unifoa7 ln0oxgrs tce59); qrm rate to a speed of 45 m/s in 15 s, moving on a circulare09;)5lxt 7gsaqnco r 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 ofdbfmx2ascsk nr) 3sbj*l3**1knf p +- 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 stanxrm hws;:jd 01h6n;d84dhz jiding on the Earth, due to the Moon? The mass of nh r6m:;4wh1djihs d80xdj ;zthe 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. I4+*jeh r z0e qy+-rg 09y 8*yxwfdypbqf the masses are moved 4-jy br 9g+z*yqe0fxep8d w+q0*hyr yto half of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance fro3e+q4 -ijou nvv-xk ln; wtz-t(z k7m+m the Earth wk v7z uv;3-n j4ko i++ntzq( lx-mt-ewill 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 4w29ztqh :f xyis $7.4 \times 10^{22} \; kg$ 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 "spacfwch t5)z16rcwn hb1:.yx r8xe-walk" at a distance above the Earth equal to the radius of the Earth. What is her accelera rzw bx r)xyc61thwf5hn 8c:.1tion due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surfaceht c3o(p)r-a b will the acceleration o( ) ptrhaob3c-f gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface eq- uia835k0szigr( wu lual to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acl(gui8 3 aw k5u0ri-szceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planethl1f4kmq, fkb8. j j6c's center, the acceleration of gravitylfmj6 ,khk4f b.c 81qj 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. lnexm b xo7,s-pr 627 jv/slq+ nm*fm1The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface,r,vmj msx *l-qnfm+ln 7oes/7bx 2p16 what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goa1p3mbf6q.f8oorf te.8 sd;a es from sea level to an altitude of 5000 m? (The mean rrqm3o d 1.t6 oe;8af.a fsfb8padius 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 above the Ew0(dm2; p.lnnuvh gc7b (1kalarth's surface. What is 7 a;gvpm(cwh.2bnk01lnd l( u the satellite's weight?

  A spherically symmetric planet has four timeswh,w25 f/hf ryr6ig 6wpv+px- 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 w 5gi+v r6phw/p,6fy2fr-whxplanet?

  During a lunar eclipse, the Moon, Earth, an- w9b8f :ui;9pcxp . h;vslpjld Sun all lie on the same line, with the Earth between the Moon and thpxhsvpf-;wi9lbljc8 p9: ;.ue 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 transport.zg8y3hqieo62 oyzm6 3 hnv /oed 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 (inix no:. vwkb*x+ 5 t0z6dh1xas(lob9.e., it just skims the surface of the Earth). What is thltab xoxik9*d 0+1 :hxon .6bsn z(vw5e 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 theyqn8si-5 vdj d)-l2dy Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earthjn-l8dd5q- vsidyy2) ? (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)9cl2q0hv(fjf .grb z Earth. It is observedlg.09vqrf b2h() cfzj to have 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 Jupiter, hastjpnr-*)q am, 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 Jupite7cdm( io. 8tn*-lgl oir 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 r1e9oh fg *dh:nadius r, and moon B has orbital radius 4r. Moon A takes 20 days to com *denho 1:hg9fplete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is m,) (xqgih ;5rdwk -nu$7.78 \times 10^{11} \; m$ 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 orlom dx1ds79.q tn xl3:bit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the E sd n9x1qm3 l.7x:dltoarth to the Sun is $1.5 \times 10^{11} \; m$.)