Is it possible for an object moving with a constant spyvd0dv ;5 v(x rzne9e1eed to accelerate? Explaiv 9xd(d5r v;ny1 0veezn.

  Consider a particle moving with )4 a8x2 ymvuy8nbea8pconstant speed such that its acceleration of constant magnitude is alwaysp8b4a ye xav mu88ny2) perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Comparew0cmp+fjo71 g the direction of the g0m f7+w1jpocobject's velocity and acceleration vectors.

  When an object experiences uh1z(tc8g7ngvi7p mdv f 9 u+e/niform circular motion, the direction of the acceleration enu/mc7 78 gpf( h1gzvivd9t+is

  Consider a particle moving with constant speed12/ m7l7b ssby-bv iss such that its acceleration of constant magnitude is always pesl-s1b my72b/v bsi7 srpendicular to its velocity.

  What type of acceleration does an object moving with constant speed in a c1 m l-oxm:6u: eghsw,circularm,hsx-e o 6wc:gm1u l: path experience?

  What force is needed to make an object mo9ufixgtn(a i(; 2k m(jve in a circle?

  When an object experiences uniform circular motion, ts; pjf7uv( ze1he direction of the net force isv1s7u zpj(ef;

  A roller coaster car is on a track that forms a circular lohuapij*jno f. e +j4-5op in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is thej5o i -j f*+uhe.jap4n minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (rad 5vg550s7pnr5w oewkl9 sh;gm03melmius = r) in the vertical plane. If the car is to just maintain cm5g7k ;h5395 lswm0lw0e spg moen5vrontact 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 sezl;1gpg25 gu3m kf;a ctw+ei0mi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on ufa 3; ctg0i5k+wleg1 p;g2zmhim 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 rad3b4mzg.) 8la9 /u n wae*phjyeius $r$ 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. Then7v .p ko+pxcb7 it goes around the same curve at half of the original p.7xvo kbp7 c+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 at a constant speed v. Then ir,n4 -n1m nkm-q6lby ft goes around a curve of radius 2r at speed 2 mkq,l-n fymbn16 r4-nv. 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 th;ik- hc syf3k )g:wft/e road is frictionless due to ice, the:kwict /3h)gk ;syf- f 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 ban0u7tegmnbgov1z y (*f:7nxl +ked 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 radiu0ulmg voy:+(ztgef 7n1*7x nbs curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsledyj9 j40,wb d aiz(mbjjz.xo:1 track is not constant, but increabi bd49y. (z,j:x jjza1o wm0jses 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 they do this?

  Is it possible for an object moving arounl)l/svqp suxjf+l5:3 h w:;jcd a circular path to have both centripe ;x/sf vq3p:l +lujj)5c:whlstal and tangential acceleration?

  The gravitational force between twoh *e/ox6s ba2z2/hq* kj ilv1d objects is proportional to

  The gravitational force between two objects is inversely proportiona33(w j wmmuau9l to

  Two objects attract each other g6zjsc079(wqvfd;+o, d.x joetu 2 churavitationally. If the distance between their centers is cut in half, the gravitational c vwsj.j+h oq7;udoduxe,02(tz9 fc 6force

  Two objects, with masses rp y, *my09vmbc2ki4q$m_{1}$ 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 zyz1 (uhn6 kg-$m_{1}$ 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 gravit+0w8ly 4alz)ev -yv fb.gv 2ouation.

  Compared to its mass on the Earth, the mass of jpxy;oa )a)5h r cc)(2 fi8axhan object on the Moon is

  The acceleration of mxobyrn u24ud9 e5s1)gravity on the Moon is one-sixth what it is on Earth. An object of1d)unry2m5b49 xoseu mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, 75lo1uu jbjkl.i3lh 1 the rocket's weight

  A spaceship is traveling to the Moady;)t9vi*l g on. At what point is it beyond the pull of Earth's gravitg )a;tydvl9i *y?

  Suppose a satellite wykfk f9f++ x4kwom1d+ ere orbiting the Earth just above the surface. What is its ce+ 1wkxomkfkdy+9+f f4ntripetal acceleration?

  A hypothetical planet has a mass of half that of the E r9t0ohocw)qh 0i be dyu;mh75a(7r3qarth and a radius of twice that of the Earth. What is the accel7 30dr tbua70yqhc 9 we)(ih5orqh;mo eration 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 E 9z i2g+9a52vxyyi o umcqzr1xc w3-5varth. The radius of the Moon is one-fourth that ox2izac5o c2z5uw my qv 9x1v 9+3i-ygrf the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has ;uth ygt 4ql:(xb(6prtwice the radius of planet A. If planet A has mass m, what is the massbu:( l tpgr(y6;qt4 hx of planet B?

  Two planets have the same surface gravity, but planet B n; 8 mfr3hl2 a0mc0db;r+ ptnthas twice the mass of planet A. If planet A has radius r, what is the radib23 n0h tmcpnd ; ;mal08rft+rus of planet B?

  Consider a small satellite(r y+k5ldpxk5 moving in a circular orbit (radius r) about a spherical planet (mass M). W5x kpy l(dr+5khich expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the *xzzbj de24 -xxb5p4dsame orbit. Compare the two satellite'xj e pbd4xzzx5b42*-ds speeds.

  A person is standing on a scale in an elevator acceleratk8aueq -nqpcs8e s;+ -ing downward. Compare the read;e-usknce +aq8-pqs8 ing on the scale to the person's true weight.

  Who was the first person to realize that g6 e+p- :u/ rj.fkgrr5q* ixvmthe planets move in elliptical paths around the rgp*/:5-r rx fei jm6q+uk vg.Sun?

  The speed of Halley's j64*clr1kwq gw *k)dg4li 0ji Comet, while traveling in its elliptical orbit around the Sun,w6g1 ql44kjri) clj*ki0 *wgd

  Let the average orbital radius of a planet xvqb (i: o+)dby3h rwt1ztl gq iq4d;h7:/+xabe R. Let the orbital period be T. What quantity is constant for all pilwor xi(7 3dx:t4 yz)/qha +h1bvgtqd +b;q:lanets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy And gngi/et -br9wj w)29iromeda, with the same orbital diameter as the Earth around our Siiew 99b g)-j/rg2nt wun. 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 is defined as one "asa)a,q ,pxfl+br+pe t+tronomical unixtp,+r ala+qp ) +bef,t" (AU). 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. .ckilx9 cc.*:jca8t8gtl 1ju

  List the four fundamenc - q6f /by;o)qkkm1ktw9yud8tal forces in nature.

  An object moves with a c7 /rivkhcv(et 9gi7 x hmrj ;la1292rronstant speed of 30 m/s on a circular track of radius 150 m. What is the xvrvh/ritr229ie 71 a7mc9 ;(rkghjlacceleration of the object?

  The maximum speed around a level curve is 30..s:x7by*scbe 0 km/h. What is the maximum speed around a curve with twice the radius? (Assumbx.*7s cybe :se all other factors remain unchanged.)

  What is the centripetal acce;o6iuknn 5je-eo- h q1leration of a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike is;j5-ohoiu q6kn1e-ne moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/0oz1 92mqxxm8dz(3bz/j z0zmtxw d;is is located 0.200 m from the axis. What is the centriw z( m0xmm x2x8;od391qb0z z/ zitzdjpetal acceleration?

  How many revolutions per minute must a circular, rotating space statio .htr9mbtcx*qy2q 1*m n of radius 1000 m rotate to produce an artificial gravxmh1m9*ytr2 .t cb q*qity of $9.80 \; m/s^2$?

  A motorcycle has a mass of7sb;i7.;08e8qcjldef,p z bq 5w pflu qb;4fl 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on ted74 l.c8;z 8b i l0 bfjqfb,se57ufp; qwql;phe motorcycle?

  A 0.50-kg mass is attached to kqnxpcc(3g x2pw *;,b the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum cgxx*n(c ;kp,w3q b2ptension 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 stri y4ktb k(5n(x6 : fuebtrxh7)hng 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 s n:b hh6(kk fx5y)utr4ex t7(btone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attaci,2qp :mi6*, xq- gccy3wwrw mhed 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 sto-3cm*2cir mq iwpqwy,w: 6 gx,ne's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when pu3ckdpen;txke1 s5cr6, .+gtclling out of the dive. What is the radius of .5t1p6cdcs,;c nktre3+ gx kecurvature of the loop in which the plane is flying?

  A pilot makes an outside vertical ai9r)0 -dr havik)s.j loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pu 0.hi)9 ra) dkvrasji-shing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pi tz3l1e8;tzovlot can stand is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling o8z 3z1 lv;oettut of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s roun7rmn 5lykwiqv,c (ux+w6d0+ p . jnk o1ejb*1ids 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 mkij+5 u6mvib1.q+xj, n 7 w0rcdlw o1ypk*ne(? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flahirn fgiule xa1 :lzwf8c )/r9fr).)8 tw-.nqt curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by frictaqxf)g/l)n.. nffr r18 )-riwi zh 9c:e8lutwion 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 o8ge ljxi n//e0f 14 m/s. What must be the minimum coefficient of friction between the tiri/nle/0g8 je xes and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. Tot vcvs/ r3u .bh,fkkg;x( 8l7he coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay on the roat;vx / 8blu3gfco (. vkr7,hksd?

  What minimum banking angle is required for an Olympic bobsled to negotit*bx 2 7-pe1nnplm0t nate a 100-m radius turn at 35 ne bn 1m0xpp7n*ttl2- m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobnq/(gev y sl-yk*d,-f:a*4. e eoxu.-ri geqnsled 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 2d)dzeqo15cuq:mk2i.: g i hiu6u ;af, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at-9 lb1sp)dfxvu /6.ipe+ u caw $45^{\circ}$. 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 re y49e2es jrg,,jb/b awvolving uniformly in a horizontal circl,4webby ,2ae9j / grjse 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 8 o.o5pt , n/seg r2:(wczrdxaarea, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circula2rd.zo:/wp5nrxag8 t,( sco er 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 pro6edd :ah35ic bton 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 standing on the Earth, d x 5py)e3zo h+3pmi+(k45pk/yikvsh b ue to the Moon? The mass of)epvyhk k5i+p/k x 53 bopih4s (+3zym the 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. If the masses are +niu q4j5o9 ucmoved to half of their initial distance, what is the gravitational att+c 9uqjoui n54ractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from xr4y iu1. v4.ff.b -qaiyt u.nr ybl39the Earth will the gravitational forces u3rin4ila1.fyvb xfqu.ty-4 yr..9bdue 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 Moonj.ajd( 0u4wp m8to 8ff i0hrv0 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 Earth edg5 uo 1iiwyhq)yf)y13ya9e8qual to the radiuwi391qu yg)a oyeyy)1 fdh8 i5s of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Eart oxhn4; yiw;:ah's surface will the acc; aiw nyhxo;:4eleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times the aqr;:ikq2qa9 radius of Maq2;9ara iq:qk rs. 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 av fb4a1f7quql.f p, ;fcceleration of gravity is74p bul1qff ;f af.,vq $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surffn v:ima y.p u/sk:i/2ace of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what2 yiiusap/: :fk vmn/. is its weight?

  By how many newtons doesr +d(.gqx8z2o)rqssjut ,(u0li: sqj the weight of a 100-kg person change when he goes from sea levelqqls8r (dju0j) zt.gouss r,:2(qxi + to an altitude of 5000 m? (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 above hfm9/ zx3f zc 8s1vfq4the Earthvff hq34x 8/9c fzz1sm's surface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and 1zp8/,emmm9anx8 oh 8fu4 l us rb(ki9twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weighk4,smemfiau 8hx u88p/ m(n9r z 1o9bl on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun c3w 26kcut+ucu-i0 wqall lie on the same line, with th w23-ti0u cuwc6+uqcke Earth between 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 is transported to the Moon. ppake d;jc3h0b7l-(n+y72c 5xenr la
(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 m s+qj l9tnd-becx8 d udt2g259d,-eosurface of the Earth). What is the speed of the satellite? (Th8xn, dt -25 jtc+e9-ed2mdlu sb9qgode mean 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 e 4j0c,ty/u ywx :,duwskims the surface of the Earth). How long does it take to make one revolution around the Eartj 0w,4,x tdycyw:uu/eh? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular osrb 4;8a- gx,b2yxest4zb(n u nr3* zrrbit 230 km above the surface of the Earth. It is observed to have asnxbrz,2x 4 r4bue tg rans;y(8z *3-b 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, l//pazm uc 8 ojce3r6+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 planet withknq+o np r1(+ewbd0* .wvgicc-no) x8 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 hn laz0yin8 o50 luf02kas orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B tok nna00u08ilz 5 y2flo complete an orbit?

  The planet Jupiter is lpt, v(aerk 6+$7.78 \times 10^{11} \; m$ 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 14pbq9b8yo9 swb(e s 6m2 years to orbit the Sun once. What is the average distance from Jupiter to the Sunpq e86 w4bms9b9(ybso ? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)