Is it possible for an obj n;.gj*tguu qds)-kbq o- w )(;rq.d1v8 zbrkxect moving with a constant speed to accelerate? Explainwb(gt sx .-b qzjg8k)qurv;d)r.dko-n u;* 1 q.

  Consider a particle moving with coan b)fa79: j ,a.u nsfync8rn(nstant speed such that its acceleration of constant magnitude is alwayac9na f,bna 8rs(f) ny7n.j:us perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Comparen/lxg:w cjn;8vmd 1;a the direction of the object's veloc 1:;;lj xgnmwdn/vc a8ity and acceleration vectors.

  When an object experiences uniform circular motion, the directionzm2 en d(2 /s n8feu(8r9:er6stnml gc of the acceleratioe8sng d9l6t((c msn2rrzf eeu/82m:n n is

  Consider a particle moving with constant speed such that its acceleratiopt,:*t e /-dltihv4fzn of constant magnitude is always perpendicular to its velocithv/l*ez t:dtit,f-4 p y.

  What type of acceleration does an obj de hgl c3p2im97ja:4iect moving with constant speed in a circular pat9li 74pc:aei2mj ghd3h experience?

  What force is needed to make an object move in a co p0kwwito+34 ircle?

  When an object experiences uniform circular motioni s).g rwyc+5gr6os aci.7ay8, the direction of the net forceagcra7i ys.. ) o+gs6wcri y85 is

  A roller coaster car is on a track ty , 9duio1z8etx-+kp uabg b6:hat forms a circular loop in the vertical plane. If the car is to just maintain contact wa zpui1 x+ o-e,9gb8bt: d6kuyith track at the top 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 thatk w: 9)ao ,msrah(-ykv forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact row-(a ah ,yvk9ks)m:with the track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular as )mpm+;;vj -q.) mptzgb fr0prc until it is going straight up. Just as the p+sppv mrq);fzmbt )-j.;0pmg lane 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 c up2cy7ljow/,cl j4 yi/kd*x, urve 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 cona u));g tuqu+ydekx ))ax71erstant speed v. Then it goes around tha a)) 7 uqeg)xy);rx+kuu1det e 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 time, compared to the first time?

  A car goes around a curve of radius r 4hq: ax+a4bq;ma.qjy at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force ym:x q .b;44qa+haj qaon the car as it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of rai53.azy*)fdb*/o zn o gunhl urv4a:8dius r with speed v. If the road is frictionless 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 t53vr/u4.a* )nlahfn g * o zib8zy:uodo

  Two horizontal curves on a bobsled run are banked at the samtr1/apt i , sz,1gru8j(vvh3ze angle, but one has twice the radius ofgt1(vrz/ 1 vzht3iu aj8p,s,r the other. The 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 9s/+ogt6s ump Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower c/6mgus9s opt+ oming out of the turn. Why do they do this?

  Is it possible for an object moving around a circular path to have both s( lrm0 w/db0pi58v8sgd xjx :centripetal and tangent sd8mi gs0 wpv8d(5jbx0/:r lxial acceleration?

  The gravitational force between two objects is proportional hpx2 y 7du5g0zto

  The gravitational force between two objects is inve mbon dzmb ud+w04/+w5mtl(/brsely proportional to

  Two objects attract each other gravitationally. If the distance bei kj wp1z+jcsy/31plm0(/v a dtween their ce lyda1pm/jwp+c 3s 1ziv(k j/0nters is cut in half, the gravitational force

  Two objects, with masses osnb17 du az3ygi17)mt8- qyz cwt3/b$m_{1}$ 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 mas-s f oo yqjj2 bzgwme9n/*.8gh12y,u uses $m_{1}$ 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 gravitatiocdu:ras r284e;y z*ozn.

  Compared to its mass on the Ef el3/zx :u nup8isge09cwgbv4yt :47arth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An ob kx 9(j0u8ckbwjw0kx8 k9jbcu (ect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves awn(.n *bzhtgqi q8a6v;ay from the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what poin qaduez37)9njt-8vq9 mp 7m gq yjr-avpe d,5*t is it beyond the pull of Earth's gr vdgvqey59j ut mn q-a 7m 8j*qpez3adp,-)r97avity?

  Suppose a satellite were orbi4la02fxt w(- 7s raqwqting the Earth just above the surface. What is its centripetal accelews wat(q7l xq2fa-4r0ration?

  A hypothetical planet has a mass of half that of the Earth and a r*6hsg /;on hr *yak)imadius of twice that of the Earth. What is the acceleration due to gravity on the planet in te*; maog i nh6*y)h/srkrms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it 4pq.z..r hwhm is on Earth. The radius of the Moon is one-fourth that of the Eah rw.m.h. zq4prth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the radig(p6: ktdf*p yus of planet A. If planet A has mass m, what is the mass of plgt6*kpp:( y dfanet B?

  Two planets have the same surface gravity, but planet B has twice the mass o oqws4hx5 nr--f planet A. If planet A has radius r, what is the radius of planet B?on-wq5-h s xr4

  Consider a small satellite moving in a circular orbit (radius r) 46ao5- kycv;u sfab6rg 7;pk eabout a spherical planet (mass M). Which expresr ;4bsaacg6p 6uo- kv;5kf 7eysion gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the sap* csuje mxs /r):)n0ume orbit. Compare the two satellite's pu*:)sxsenm/0 )ru jcspeeds.

  A person is standing on a scale in an elevator acceleratimpyv2 :eu )d1nng downward. Compare the reading on the scale to the persp)m2u1 n:ydve on's true weight.

  Who was the first personsa n:l.jou 1;h to realize that the planets move in elliptical paths around th.o jnla: h1us;e Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around u-hk.3zkh93jib y (sb the Suns bk 3yhib(h-zujk39 .,

  Let the average orbital radius of a planet be R. Leth7r1itcl- u*,,yg el q v5xti1 the orbital period be T. What quantity is7-u5ite llvh ,c1ryqx , git*1 constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy And9/;fgl;baxz p 0,fog(tq2+zn+hp lskromeda, 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 planet be, compared to thepzfalonxg; sb/(g9qkl+; ,+ thp2zf 0 Earth's orbital period?

  The average distance from the Earth to the Sun is defined asqsay7l-onk fa4 1o5w: one "astronomical unit" (AU). An asteroid orbits the Sun in one-k 4oa o71-y:wlaqs 5nfthird of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.rg8(/55 ac t5.gkxyv hdjy q+y

  List the four fundamenqce6d d49prz 9lnbot-( /;zwc1e (nubtal forces in nature.

  An object moves with a constant speed of 30 m/seo: gzg o2r o6x)i3dz0 on a circular track of radius 150 m. What is dz gzog2x)6o3 ie0o: rthe acceleration of the object?

  The maximum speed around a level curv p1tjno:vnz+bkf-3( u e is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain uncha+k1b-fn n3:p(t vujzonged.)

  What is the centripetal acceleration of a point on t t(t 4jr9d3dophe perimeter of a bicycle wheel of diameter 70 cm when the bike is moving d9dtpj 3(4ro t8.0 m/s?

  A point on a wheel rotating at 8j7qny;enx(z(o6 nh h 5.00 rev/s is located 0.200 m from the axis. What is the c8; nxqy(jh7oe(6n znhentripetal acceleration?

  How many revolutions per minute must a circular, rotating space staapdd7l29u4cnzs f 0ci 4-pp+ation of radius 1000 m rotate to produce an arti7dc p+zacspi20u a pnd4-4lf 9ficial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m rad(/ia3i40ktci,qv af(u 8ob qt ius turn at 96.5 km/h. What is the (qoq f icb 4i0tku(ai,va/ 3t8centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The systc2d: vh52c wwo,,mjg.rc4i dg em is whirled in a h:d42 gi.2wm ,jc wrc5,hovcd gorizontal 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 st8oww(b/ a). qyo1 hkejring and whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's8a(/ wjobk yo.) qe1wh weight. The stone's speed at this point is given by

  A stone, of mass m, is attachedo e:1fel pt +;z weyxv*mdly:,vm3:5p to a strong string and whirled in a vertical circle off yp*e,xoey ; dle5tm:+1p vwv:m3zl: 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 this point is given by

  A jet plane flying 600 m/s experiences an acce)w 6hbru7 6tdaleration of 4g when pulling out of the dive. Wdut 6wh )a6rb7hat is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the centexvfbx/ pq4to)q6 9 *har 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 weight. How faxao4qq)*f h6 bpt/v9x st is he going?

  The maximum force a pilot can stand is about seven times t31 b/sh.cnzj his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at bh n zs1ct.j/3a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve withhbetpw1 3v,o, jfyi5n,n0mtqg1 25qv the tires on the verge of slipping. How fast can this car round a secqhti, oeqw 5jpv,n g 3ymbf2v,15 nt10ond 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 50 m with a speed of 20 m/s. Thetvu;rb(lu 4uiz f9/* vf nz/y9 centripetu/n9f /(vuit r4*vfz9yu ;bzl al force 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 speed of 14 m/sp3bo gz8rnkw, y;0e9g*khek- . What must be the minimum coefficient of friction between the tires and the road for the car to make, p8oh9eeg ;k*ky-30nbzwk rg the turn?

  A car is moving with a constant speed v around a level curve. Thygnv 1,q0h; eaej1twn /x,ar8 e coefficient of friction between the tires and the road is 0.40. What is the minimum radius of t/wayn,,t1erga 0; n1hvq8 exjhe curve if the car is to stay on the road?

  What minimum banking angle is required fo+r2wn+h3ubsbb 1mgdc-an)) yr an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fricti1 wn-rumd+gb)y+)3cbnab2 shon.)

  A horizontal curve on - clmkpg.tej1 0+dj+a 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, banked ataz1(hg7pnll 4 an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankevi wqb(; zer*1x+w c:hd 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 uniforq vep+7,s13w esa*r cfmly in a horizontal circle of radius 0.50 *,sqre7cea31ws vfp+0
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 unifx 5tl2dew05 qnorm rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m.x2dq ltw0e55n (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 /2t fpyfyl5j*-hqm6t 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 ;xu 8jbb+otar*) su3oon a 70-kg person standing on the Earth, due to the Moo s xtb)j 8ru+*o3aub;on? The mass 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 attractc,e xmw k3k.gf 7u5h7nive force between two masses is F. If the masses are moved to half of their initial distance, what is the gravitational attr3h eg w,k5fxuk 77m.cnactive force?

  For a spacecraft going from the Earth toward the Sun, at what distance frov*i*jy+q qtox0 rmx,*m the Earth will the gravitational fojrx x0*i*qm tqvy,o+* rces 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 isv( e4oj-sc9 er $7.4 \times 10^{22} \; kg$ 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-walkos6z a+ r20ixg" at a distance above the Earth equal to the radius of the Earthgo60r x2az+s i. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earwsd/eqj1 6yv,0kycma2h.u wz5 k0 p p;th's surface will thehwwyj vdz; ecqsk.6pp,m2y /0k 1a u05 acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above iie-h4c,ftu skf+uond +q j8*2ts surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the accelert+qof+24nejud,cfu*- i 8ksh ation of gravity on the surface of Mars, is

  At a distance of 14000 km/ufqkmr+h7w8 u quh1lz(e s .. from some planet's center, the acceleration of gravity e +qmufzh.hkl uqs/8.wu1(r7 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 surd9* )+ ky y,vdjul4ytpface of the Earth. The Earth has radius r. If the ob+4ydty yvd),k j9 *lupject is raised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does thejk/di :- f4 nz0zhp)ig weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Eartg-h/n4)zzf kj0i:i dph 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 k g rmo7h d6. u 9t93srttwtm9path9*;Earth's surface. What is the satellite's wetm; 39rthok9s w.p7 u9t6trd tm*ah9gight?

  A spherically symmetric planet has four times the Earth's mass a crszb/od+v;67/hc 2gz )f+rc+xtrjt nd twice its radius. If a jar of peanut butter weighs 12 N on the zj rcbrd/t+vohf6; cs)+r+/ct 7g2z x surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and S:n r( x*mp0ynm0p). wqkkhtb:un all lie on the same line, with the Earth between the Moon and the Sunt:kppn )nr 0m:q by.(mh0wk*x. 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 0may5wf1xb)xpg11 i p 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 just skims the cew:s8b5q yk;7 x vl8lsurface of the Earth). What is the speed of the satellite? (The mea ys8lxlv:7c kwqbe58;n radius 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 skims tdvd7r1k br(a y ; 2g1gutgyq-:he surface of the Earth). How long does it take to make onu7y 1dtryvk;:a2( g gdrgq1-be 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 the Ea 1cnkzr/uvrm2 3 w7nougir * *w5,/uttrth. It is observed to have a period of /tn k,*tg3*mwr u1z r 257/oicrv uwnu89 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 Jupitpuj41y9:2wqa rt +zsj/ /-ef1aw. nnpgtbw(rer, 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 of Jupiter orbits the planetl5 cba-tici 82 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 radiuuv/u )f9c j2ips r, and moon B has orbital radius 4f/v9jicu2 pu) r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter i4rkhjrml-9j01jy2 +ikjer s (s $7.78 \times 10^{11} \; m$ 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 yearsuup4*lp:3v dn to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distalu3d4 uv: *ppnnce from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)