Is it possible for an object moving with a constant speed to acbci.+txtqy+ x8ykyl l-v g 1(v.g,yd. celerate? Explain iy l(v- .yt.vbtgq1xx+c,lky . y8g+d.

  Consider a particle moving with constant speed such n0 n1fnx2btzej,7+l n that its acceleration of constant magnitude is alwx+bn0 j 21e7ntlz,nf nays perpendicular to its velocity.

  An object moves in a circ bk1(amry h)9n)( s7rizj)p hwular path at a constant speed. Compare the direction of the object's velocity and ac zp)rya() 9mhr7skb(h )wjn1iceleration vectors.

  When an object experiences uniform circular motion, the d/g, yh7whkg2e(o g+kk irection of the acceleration iskko kg/ ,g (h+yhw72ge

  Consider a particle moving with constant0qo lo sqg6;sjzhmx *dx*2,x( speed such that its acceleration of constant magnitude i*x6jq,os2(o s qxlzdx h *gm0;s always perpendicular to its velocity.

  What type of acceleration does an object moving p3tlv2ao 1el ;with constant speed in a circular path expe laep312l v;otrience?

  What force is needed to make an ob rp2,.oa;r83 jwyaao zject move in a circle?

  When an object experiences uniform circular motion, to0qp3ovox tw,i* 6n en2eg -;ihe direction of the net forc,in0t o ;wvn2o 6ei*-3oxge qpe is

  A roller coaster car is on a track that forms a circular loop in the vertic t97bp)3jope++ qzgy6/fuuq fal plane. If the car is to jgp/67t++b)q ouu fye 3p9fzqjust 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 = M) is on a track bkt+z0 *du7zx 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 value for its speed at that poinuz zt *d7k+bx0t?

  A pilot executes a vertical dive then follows a semi-circular arc unj.gl6 q8c rw9rvq:g- ptil it is going straight up. Just as the qjr 8:g 9l. pqcw6gvr-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 curve of radi , .bbg2gtu*.k mbn7asus $r$ 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 q 0wm4x,,(x l, kldnx*u zu+eha constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal fo,(h,zmk dxun4*u+ qxel0wx, l rce 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 speupvv/c x0u3,oltzjt,j9p5 l*/u8v szed v. Then it goes around a curve of radius 2r at speed 2v. What is the cen/ lov 0953juzuvj p*,xt/vucs8,pzlt 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 sc(/v76aolrvzl n ; i1hpeed 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 mion lr7 ;h6clzv( a1/vagnitude to

  Two horizontal curves on a u nne2u 9d4nx2bobsled run are banked at the same angle, but one has twice the radius of the22nx9e unnd4u 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 Olympic bobsled tri9/0rqh,28 bwpiza o xack is not constant, but increases upward fro89xbrp 2 i0/waqz hi,om 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 around a circular path to have both ng54w5aw dz voen): r9centripetal and tangeon 95zdwv5 : )werag4nntial acceleration?

  The gravitational force between two objects is xw gt jsat8,*esbry91 nnm:5; proportional to

  The gravitational force between two oahso+ ( ((bm2is :irjebjects is inversely proportional to

  Two objects attract each other gravitationally. n1* c6so,pid0 qk8 j+ydd7 .whts :vxt1 ;izvuIf the distance between their centers is cut in half, the gravitational forceiq:w u,vo *8ssv1n dtd 0x c+yk;dpj zt76.1hi

  Two objects, with mass-wnuc, 5 hlm/ges $m_{1}$ 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 mas0hvlptpqxgn d h(.eat(3;4hc2 qn5g *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 of universj ho-79.wsf ewal gravitation.

  Compared to its mass on the Earth, the 6 dib3 nkf)fe 7n0i+hwmass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it f8 k ja*,h8rkf n-x fwbs(t+r:yrt5.w is on Earth. An obj ., fw8tf8r- r(h b:n5asfwrk+*kxy tject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Ear k9ufewb4c17qn (m,sj:rjf i fe18x3l9d.c ibth's surface, the rocket's weight

  A spaceship is traveling to o4( fl7nv7/ 7s jd fjwxpxms(9 ta:;ts5bje i*the Moon. At what point is it beyond the pull of Eartha9l5 s *x:nsodxf;7ip7tmfv4wt / je(7jj sb('s gravity?

  Suppose a satellite were orbiting the Earth jus sk65c- 2*lyx/w -exac (fvadft above the surface. What is its centripetal accelek ad6ce/y- (vfxf*wcx5 as2 l-ration?

  A hypothetical planet has a mass of half that of the Earth and ahfs 7iy )jfxv.5a+le * radius of twice that of the Earth. What is the acceleration due to gravyj) *vifs 5hl 7ex+a.fity 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 Earth. The2at hd5wew) j(um6.db radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compare2 at.6(jwdwh)dumb e5d to the Earth's?

  Two planets have the same surface gravity, but p 1mhr2/;p4w y2mzm.i 1)l+ xzni yjmhilanet B has twice the radius of planet A. If planet A has mass m, what is the mass of pwmp11 ;nyxyh+i izmhlr4m)2m. 2/ijz lanet B?

  Two planets have the same surface gravity, but planet B has twice th+ pdr; tgl.z*fe mass of planet A. If pl fz;rpg*t+l .danet A has radius r, what is the radius of planet B?

  Consider a small satellite moving i9vl5/j5r sk opn a circular orbit (radius r) about a spheric/ pv55olkr 9sjal planet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same otl dk89asvxi22.pou 5 a .p7n-c 9cdllrbit. Comll9on9. spc78id ka-a .x2lp52utdcvpare the two satellite's speeds.

  A person is standing on a scale in an elevator acceleratiyvc6(j tto 0h3ng downward. Compare the reading on the scale to the persh3c6jty (to v0on's true weight.

  Who was the first person to realize that the planets move in elliptical p 5e5apio/ ob5uaths around the a ipoube5o5/5 Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit arounk3bq0iasfbe3;*76 rfbs kke , d the Sun,qi bf336b7 kk 0ebr,*e;sfska

  Let the average orbital radius of a planet be R. Let the ouqm2c vo xx29+v7*n rbrbital period be T. What quantity is concx2+v2q b*uv7xr on9mstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, w3(/zgnqmp ,yrgw7 poi.*s ko /ith 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, corz3qg/ , w*(7ks/opmip gn o.ympared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as oqn 0+0nuyn(8 v4 f vyfj1*7,ylabuhwl ne "astronomical unit" (AU). An asteroid orbits the Sun , 1vl4fy nun8 a vbhfyyl0*nwj(q+u07in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.ioyg+ny0u t+b s,jh45

  List the four fundamental forces ;*(bb nuq2)ttxi6(djky7a r oin nature.

  An object moves with a constant speed yz+pyw5 oqdj uaq8pw y.1.81x of 30 m/s on a circular track of radius 150 m. What is the acceleratio yy.1ud+xpya1w o5p 8qqwzj.8 n of the object?

  The maximum speed around a level curve is 30.97xvq,ezq 40p8 ahng)hhgu7t0 km/h. What is the maximum speed around a curve with twg7x)vu ah, q08zn7ge4p hh9qtice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a , ia8eh9pv b:lpoint on the perimeter of a bicycle wheel of diameter 70 cm when te:v il9a8 hpb,he bike is moving 8.0 m/s?

  A point on a wheel r;u,ykgct8oe. clsf*1 otating at 5.00 rev/s is located 0.200 m from the axis. What is the centroscu81;l* c t.e,f ykgipetal acceleration?

  How many revolutions per minute must a circular, rotating sv/*x /hjk7uokpace station of radiusvkhx/k 7u/j* o 1000 m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius tu rbhf( zy 0noixdz*-of-;i/)brn at 96.5 km/h. What is the centri;(oho-bnfi x brf*zd-)i y 0/zpetal force on the motorcycle?

  A 0.50-kg mass is attached to the eh;zu g+bs *reo*n9qll.v+g w)nd of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension thal.o +*e b+9rg g;)u *snlzqhwvt 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 af *w6h(e): cx :hinjaqttached to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tie*(cwjq ax6:h hf:n)ension 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 sto/ yi7p5tf6waring 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 7a ofy/56 tipwstone'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 pullinchdv/;. zyg1j g out of the dive. What is the radius of curvat.yzh g/1 dv;cjure of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of thlnug* r*z sp-n .,bcu/e loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat wi*/*-lpz ug sbnun,c.r th only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times his weifd me*:vvz5( lght. What is the minimum radius of curvature thmv*lz (e:v5 fdat 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 tires on qftp(xm kl+lc5cb5 v+o79f.f the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient of friction between f+ l(c l5movp9ct7bqk5xf+.fthe car's tires and each road surface.)

  A car is negotiatingxai82+rrkibc,e*c3 o ah :wy4 a flat curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by friction r: k+iocihe , wac82r*xba4y3is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 50 m at a speed of 14 m/s. Whd35xg3ylo d (oat must be the minimum c53 go (yxdo3ldoefficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v arox1pb .kqscsg 4x 2n0-jund a level curve. The coefficient of fqgnkcj10xsbp . sx4-2 riction 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 road?

  What minimum banking angle is required for an Olympic bobsled t* l khsmlxl6x ./3c(lbo negotiate a 100-m radius turn at 35 m/s without skidd lbsxkl(m3/l*cl h6x. ing? (Ignore friction.)

  A horizontal curve on a bobsled run is banked.pwuc2*n7 /qnym 4mla* ui*f -u effe; 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 radiuhf yuu-gw+r 63s 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank*,yn1 nri1p6ga qo 0cf,w 4yqfed 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 revoleoziwnc*pa:tm .+-q/ra,pk e 9 u(uc 5ving uniformly in a horizontal circle of radius 0.5p5(.upw +zq rn:9-/eaeiok a,*cmc ut 00
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 uni+nm(mn c5ic,kform rate to a speed of 45 m/s i immn(5kcc+ ,nn 15 s, moving on a 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 ofs60as2q)gcf (s:q pq a a proton 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 Ea/-zf h)niqxl4rth, due to the Moonzx4 l/ihqn)-f? 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 betw3 oaa j4aa)+cc -bscq7een two masses is F. If the masses are moved to half qcoaa +3 c7asc4)ajb-of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what disth0)*csb ceh)n ance from the Earth will the gravitational forces due to the Sun and the)c*censh0h )b 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 i e u-ngeq*d(o1ca;h6nat s:tp +n6e x+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 "space-walk" at a distance az)uw0jv1+ 6dijx cx 6tbove the Earth equal to the radius of the Earth 6 jcjd z+6u)0ivtxw1x. What is her acceleration due to gravity?

  The radius of the Earth is R. At wh1bt, ite3t3l f1t u;/v4gbehzat distance above the Earth's surface will the accel ht4/ui3tv1 b,z3 e gbtltf;e1eration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance abovh /rn4vua.u+ye its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, iv +a hyu4r./uns

  At a distance of 14000 km from some planet's centek .g1vpdzotal 8b*5/ir, the acceleration of gravity i 8d lvi /g.apbzt1*5oks $32 \; m/s^2$. 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 Earth has radius r. I 1ubiox;d*y5lxr;r6x f the object is raised to a hei;urxo6x1ly d r*;ib5xght of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes frr t i:u/l1o) 4oug3feiom sea l 3ioo/ie u14ugf)r:ltevel 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 c a:he17itv v2 c);lu u06js/izg eaa*point 3r above the Earth's surface. What is the sata h:sa 6c*j e i71v i)/cz;ulvaegu20tellite's weight?

  A spherically symmetric l b432j**dl - zy,;orrvymvym planet has four 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 planevl3 ;b4djrm lvo,myyz- y*r 2*t?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on th jas yka3;yin;c8jd;79o e.fue same line, with the Earth betwejso8a3 auf;e.;c ki9;jdny7yen 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 i -th.c,o,q ibMoon.
(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.,krsvp;,lp261ou e dh: it just skims the surface of the Earth). What is the speed of2 op:l ; serdp1hv6uk, the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit abou:us:l04 9uap2a8 ig jbqcnk2zt the Earth (i.e., it just skims the surface of the au a:4 juiqbp:zsg0cnl8k 22 9Earth). 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 the Earth. It q3yo,7 01,pnc/opg8q q ij zuhis observed to have a period of 89 min. pq3nc h7o0z,jui 8pq/g,1 qoyWhat is the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter oss fz k8- frjp3v:x+6ubz+e9m f $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orbxd zbps89h+u 4its 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 ne wj. r mmxz4kav)8us6*arly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moonswu)z ark8*mm4vx 6. j A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is xl065/0 ,zvif;gy fbswen2yk23ylcq $7.78 \times 10^{11} \; m$ 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 Jus5 yn72v0s jblxondiv12w,)a piter 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance a ni10, oxvd7) 52nvsw sjby2lfrom the Earth to the Sun is $1.5 \times 10^{11} \; m$.)