Is it possible for an o n8u8:ba f)kn7g3l huwlt87nbbject moving with a constant speed to accelerate? Explainf37 l7)utg8nl 8u :b8nhbwkna.

  Consider a particle moving with cf;i a3;q; 6hi ,fb8-vmgc yxngonstant speed such that its acceleration of constant magnitude is a; q8h;n,m-; xa cgg3 if6vyibflways perpendicular to its velocity.

  An object moves in a circular path aty9m kz+ qhfbf n.vw( vj(xzw;k0+k 1,(q* sdnb a constant speed. Compare the direction of the object's velocity and acceleration vecny,1vs(z*q kf zwkjv;b fqnh 9(m( +d.kw+0xbtors.

  When an object experiences uniform circular motion, the dir )r qv2xtceun(e,seg8fn, u28ection of the acceleration ice f8 nrvu, es),uexn(8qg22ts

  Consider a particle moving with constant speed such thevnjabd-5( f 6452 .h sqejjj, rrv6b-k3rlczat its acceleration of constant mag c rd (z-ns .jj4eaj,qkb5er-5fvv32hl 6b r6jnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with consta8.8w::x kjxz y-abqk dnt speed in a circular path experienc:.x:dxy8z kq8wa-jk b e?

  What force is needed to make an object move in n9dos c8xcp /0a circle?

  When an object experiences uniform circular motion, the dir 03ct qwiic/l/cdr j6vs( ,,b0frep2 fection of the net forcevf0ccjt3 (bis f,d,qlre/w0p2 i c/r6 is

  A roller coaster car is on a track that forms a circular loop in therk 1d4ax yk,4f 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 centripetal accelerati1ykrfkad ,x 44on at this point?

  A roller coaster car (mass = M) is on a track that fobajzgq o h0ru2w. )i -5l)bswb, j88ydrms 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 ibghb,r)5)w8y lsao 80ijj-w.uq b zd2s the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc until it(qme-;yf0nnytj q 0 (a is going-qqt;yjm 0 ya(nfe n0( 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 curvekopg(h6 ce7 m( 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. Theqo *ph.piu zf - -ax lai+by3-pi0+a6yn it goes around the same curve at half of the original sa+q 3+a-pl6 i ibu -*yxo-.pi0zyhfpa peed. 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 iot03 gt4x :i8sk6agm of radius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centmt4s:agx6 80igki 3o tripetal 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 the-;u7oyn7*+ 0z chez8zsv w1mjt6nip,ni+a q c road is frictionless due to ice, the car can stilp,csm c hz-wn+vq iaio8nn7;7ezty 0z6 j* 1+ul 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 ar*ds: 99vqorz we 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. What is the safe speed on the 99qovdzs:r*w larger radius curve?

  The banking angle in a turn on /(pzf0qskrb-yj+ g 3 ythe 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 coming out of the turn. Why do they dob- ykqj gzsy(p+0f3/r this?

  Is it possible for an4ru9rp /e;jxe object moving around a circular path to have both centripetal and tangential acceler9e/ep;u rj4 xration?

  The gravitational force ben-kyxz ; f37c8aep*ivtween two objects is proportional to

  The gravitational force betwi glyr*u bsteq ;9)j 8jib.17teen two objects is inversely proportional to

  Two objects attract each other grav1aub8d 4-( (gudvvikk7a pnm7itationally. If the distance between their centers is cut in half, the gravitatiod8ui u1p(kavn (v gab7m-d74k nal force

  Two objects, with masses z9adw9n 1e4(bbr9yy p$m_{1}$ 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 qh(rk;f fcwhc-oc 02;ses $m_{1}$ 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 omeo ji+6u. 6cjf universal gravitation.

  Compared to its mass on the Earth, the mass of an object on th8xlw brpchu+pi5e pr5 2.h1:-gx7v;5bwunt n e Moon is

  The acceleration of gravity on the Moon is one-sixth what it is /kk-pxctw1vm 1zrq8 2amh9i9- behu o:3uco 6on Earth. An object of mass9 zbm962iku1vh31 :q-ho o xte 8cmcaku-/ rpw
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Eart29v, r6qcmy5dsv.- sv mbcg :nr) l*kgh's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what poi/ff)b+t6cw i ed x6b iq4wl9p6nt is it beyond the pull of Earth's gp 6l6betw6idb4+x9/ fq cw)fi ravity?

  Suppose a satellite were orbiting the Earth just m9l3/3 dv,ay,(3qn nt:mk.hh nbfiovabove the surface. What is its centripetal ac hkyn3fm9, tv3 v(nd ,h. m/qni3alo:bceleration?

  A hypothetical planet has a mass of half that of the Earth and a raxc7cw9i6uryj t+ ,v e)dius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the accelerat) cuv+t6 wce9,xriy7 jion due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth whcobg 91lzh*n)-e0s yp at it is on Earth. The radius of the Moon is one-fourth that of they o0gc -nlp*sez91)hb Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planew.p+c42c eak wt B has twice the radius of planet A. If planet A has mass m, what is thec ce p4w.2kwa+ mass of planet B?

  Two planets have the 8j6hycj-r/gr1dwt 2ysame surface gravity, but planet B has twice the mass of planet A. wd6 j1yrgj/h-y28 tcr If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (raml( /mkq)do:j 8z-i0+5b+ ejqpyqcd ydius r) about a spherical planet (mass M). Which expression gives this satellite's orbitdbq d+mm)-( q8q0pjo:/e k jlz i+y5ycal velocity?

  Satellite A has twice the mass of 1obc x,l zw+sw* j+9pssatellite B, and rotates in the same orbit. Compare the *xwz1,s+ +bw jolpc9s two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compare tzh/ rkh*m: a6v 00mykrhe reading on th0mh h6 /0mv*razr yk:ke scale to the person's true weight.

  Who was the first person to rqkky8- (cyy b;x749pyplkt4 zealize that the planets move in elliptical paths arounl t;z4k k- yxb4 (pyyyk78qpc9d the Sun?

  The speed of Halley's Cometj8u:i mj7+7b4 qjs kry, while traveling in its elliptical orbit around the Sukb: yjs7qj jm 487i+run,

  Let the average orbital radius of a planet be R. Let the ojwujr65g- *pblv 0jno )(b dc2rbital period be T. What quantity i2d5 wgnbco bl-j* uv ()6j0jprs constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, wif1f ij81hvz rzf ,kzs*b9j1/vth the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of or 1*fjfv , 8kb91z jsz1vzf/ihur 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*vi8xbn. pe0,xxbv 4n one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distan4,in.nxvpx b0bxve*8ce from the Sun?

State Kepler's laws.l4kiy :b 5w k23rqj.wh

  List the four fundamental ftlm //h7 iolt0orces in nature.

  An object moves with a constant speed;jq7gk+ :obkuk-8h za : :ccgiej93qb of 30 m/s on a circular track of radius 150 m. What is h:7 93kk ag:;j iqck+o8bbczqe-gju :the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/hpcval exw4 2*,. What is the maximum speed around a curve with twice the radius? (Assume all other factorsl,w*eavxc2 p 4 remain unchanged.)

  What is the centripetal acceleration of a0l8 kad/2f nan point on the perimeter of a bicycle wh2fdnak0a/n 8 leel of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s x0dh v/y )5/gejscb4kis located 0.200 m from the axis. What is the centripetal acs5h d/v0bjxec) gy4k/celeration?

  How many revolutions per minute must a circular, rotating sp,o2h 2*jdyt.rwe1 cuai/ c 3gtace station of radius 1000 m rotate to produce an artificiaha, uc2ieytj1. wtg*o/23drc l gravity of $9.80 \; m/s^2$?

  A motorcycle has a masx5,x sz/v 8du) r sghh(b(.qxzs of 250 kg. It goes around a 13.7 m radius turn at 96.5 km/zv,5h((/zs q hsx )x8r.bdxg uh. What is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to fpliyv 7(mh *rv+x*f6the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can p7r* li+vfh( mvfx6y *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 / wh7s*ehc( ww g*ff;lstring 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's weight. cwsfwf / ehlh**g(7 w; The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and lvn+sbr)uiu2b45c .p.d 6sbowhirled in a vertical circle of radius r. Atb+4u.io5b )rd2svs l p.bnu6c 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 acceleration of 4g when pulling7 g*drpnp:0k p out of the dive. What is the*rppp :7gkd 0n radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which th1-g m3 dvc4aa)hb(i5sl( xewx e center 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 hg45a -c xvwd3habem(1ils(x ) is normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times his wl-h*+x-,zaymyxu e8 eeight. What is the minimum radius of curvatyxh- l8m,+-*u zxeyaeure 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 curve with the tirf4ssmjwvcf48qv6-w/ i4l *f tes on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient of frictio6sfc4i/ qwwf* m84-v vjtsf4ln between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50n1q.d g( t0ytzkmmu7+ m with a speed of 20 m/s. The centripetal force prd7mq01 tut+k n.my (gzovided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of ra 1m ej6,6dens.yld omp-)au.fdius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to make the ,e6da .lo6yf1jp mdus.m)ne-turn?

  A car is moving with a cons t )neyke:0 mi3z0nnm0:sm*i btant 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 curm i0im )tn:0s0ezbk 3nn:*eym ve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negotiate a 100jwyp,jpk m38v )f 4cxyw 6-gu)gf w vp y6)c3- xujk8y,m4pwj)-m radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled runz 9fz3v(;go kz 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 curve2f k(u: bmtnkq rlo60cam+cxoe ;8e57 of radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at ;3l ak7q ep(z*sr db tzl5 /q3wr8tez)$45^{\circ}$. 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 vrch shs jhlyq:0b4em8d7(/+revolving uniformly in a horizontal circshb rq8(:/07 dy+hsh c ml4evjle 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 pi75q v+ sk50 rzh,elqmxwf6b-xt area, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical valub0 qx hxk7-+vr z, mflsw5q65ee 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 mass kaw,g:bw4i 2 d$1.67 \times 10^{-27} \; kg$ 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 gravitatios utl2fzaj-15szd 5,mnal force on a 70-kg person standing on the Earth, due to the s,ujlztd z12 55-msf aMoon? 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 attractive force between two mawi.5:g f7 acjgxhs na:)a4+7r zdgaupa*80 sksses is F. If the masses are moved to half of their initial distance, what is the gravitational attractive f.7sfjg*krdwg)sacu:p 0 az 5haga8i:a47+n xorce?

  For a spacecraft going from the Earth toward the Sun, at what di s:g (yogh,jt:stance from the Earth ws:(ot gh:,gj yill 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 iv/2fpqup* 1u;lm*u k7s1f ckl s $7.4 \times 10^{22} \; kg$ 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 "sphp 70hl,dryi3j r t;z rj3ny,9ace-walk" at a distance above the Earth equal to the radius of the Earth. 7hy 0lhdtjpn9z3 ,r j;r i,3ry What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surfuf buo3z 58gtg-1hv-y5 1zpmsace will the acceleration of gravio35-vszpyu5fu8-tghgm b z1 1ty be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance abumful- p6(0s0zm foo8l 1ms f(ove its surface equal to 3 times the radius of Mars. The acceleration of gravity ofs foo(-uplmum z81s(6l0 m0 ff the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km fro65l k-agup.1tpvg/ fv 5dyzk 6wt2c;n m some planet's center, the acceleration of gravity ip6kn -dwv 552 6t. u/gacvtyzfl; g1kps $32 \; m/s^2$. 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.0vid d+jlo8jh vw 99 i*s;i:gn The Earth has radius r. If the object is raised to a height of 3r above the Earth's surfawvvd* +;9i o nslh:j8ii0g9 djce, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes froma0lv.vc0 ( yo)bbcx 4wn )v:ym sea level to an altitude of 5000 m? (The mean radius of the E b0lvyc):04vx.ym b)(awnvco arth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite ofku(3/rhwn 6 woj0qtd ag au15t*, ia;e mass 100 kg is at a point 3r above the Eart,d ( h1*kq/ g rnoa uwi3eu0wata;5j6th's surface. What is the satellite's weight?

  A spherically symmetric planet has fouas/:x7wwqfk rxdy3 c+p)s mw :lk6j50r times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth,scdqw:+)/ 7kwl3 ar y0f6s k:j5wpxxm how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Scwrr5+w n;b l9un all lie on the same line, with the Earth between the Moowc;n rbw9r5l+ n 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.cr0.as7 ly 6l6mhy oo2. w2cns
(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 justham9em/x 4 , v01wy/5j wmsvoh skims the surface of the Earth). What is the speed of the satellite? (The mean radius of the Ev/hom4jsxw1,5vh y /w e mam90arth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low cirj2v7u0yj kgd- cular orbit about the Earth (i.e., it just skims the -v2u7d gjyjk 0surface of the Earth). How long does it take to make one 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 tg,dyi (,+dv+a. zsv ovxeu 1a.he Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (as.zg ia ,yddo++ ,vue.v 1xv(The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamerz 7xzj*38kjuter 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 with a radi m09px*d7;k bho;n .;wm.bmgah6 ing dus 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 radius:cx2 s4rdt4af r, and moon B has orbital radius 4r. Moon A takes 20 days:a4t sc4df2xr to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is uzr 8*u1-46sw moz xas$7.78 \times 10^{11} \; m$ 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 Sbl-/b0,nv rq qs+qoh 5un once. What is the average distanqq5oqvn hrls0/ ,b-b +ce from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)