Is it possible for an object moving with a cgr4zznxp9d00v-nf1fmd ) qw1 onstant speed to accelerate? Explaig 4rdq 9f)znf -m1wz xd00pn1vn.

  Consider a particle moving with constant speed such that its acceyygu/icx(+p n,4d sy;s e hw/o8 sw);dleration of const/usspxg(yy 8ewy d +hdco)4wn;,/;s iant magnitude is always perpendicular to its velocity.

  An object moves in a.kol0d .l d8iy circular path at a constant speed. Compare the direction of the object's velocity and0 i..ldk olyd8 acceleration vectors.

  When an object experiences uniform circular motion, the diwpz7 b +p.nbx;rection of the acceleration isn.p+ zx7b;pbw

  Consider a particle moving with constant speed such that its qm 36-pq1c8o lafq2bcacceleration of constant magnitude is always perpendicula1f3ao pcc8q2- qqml b6r to its velocity.

  What type of acceleration does an object moving with constantdv; (77c5y0 bagsigi q speed in a circular pa5va;(cgbdyq7 g7 i0s ith experience?

  What force is needed to make an +9 nt+g-ef o3c:xdu spobject move in a circle?

  When an object experiences uniform circular motioene1v:4nk2y.xq p q9 mn, the direction of the net force yq kn2 qxe4p.nem:91vis

  A roller coaster car is on a track that forms k.vf+,ufv) w* ro+mlda circular loop in the vertical plane. If the car is to just maintadfu*om. +f)vw kl,v+r in 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 ha,29 rj(mx4 tus*noi(mass = 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 iu,j9rx (2n o*4at mshtrack at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a verti cjts 609ao3rtcal dive then follows a semi-circular arc until it is go t6 9jtc30oarsing 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 curve of ra fw8e i1vm.:1,sgps wrdius $r$ 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 )sv.1fkkfz:rnkbz2 - v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around the curve fo2k):fbv .szfk1 rkn- zr the second time, compared to the first time?

  A car goes around a curve of y qxnrkbwm3,e)34r q* radius r at a constant speed v. Then it goes around a curw)33xmeqqnbrr4, k *yve of radius 2r 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, .zs3k s7zxv dg8b;gg curve of radius 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 eq; s ,bggsg7vz8 dzxk3.ual in magnitude to

  Two horizontal curves on a bobsled run are +)qiw zmwm i*hc:0(z9;yrpdy banked at the same angle, but one has twice the rad(0 +ciw; qrm9 )ydzyp*hw:mziius 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 larger radius curve?

  The banking angle in a turn on the Olympic bobsled tra.)qq w7iftaqa- 38d qcck 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. Whdq.3i -ftq8 7)qc aawqy do they do this?

  Is it possible for an object moving around a circu h/tqo.etw* l.p7xpj994qeyklar path to have both centripetal and tangential acceleratioptxkl o7t4.pw. ejy9/eqh *9q n?

  The gravitational forclcphit6kdh zl+; 1y *:e between two objects is proportional to

  The gravitational force between two objects is inversel -jfw,ks: hk9h:bf s, xjv5t;vpz,i8 jy proportional to

  Two objects attract each other gravitationally. If the distanc 9ay/ t1rpo:cue between their center:c 1r/pot9uay s is cut in half, the gravitational force

  Two objects, with ma)pvwz uf,c/ drc1l5e )sses $m_{1}$ 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 y550 82*lvw qy0wnmda* eqboises $m_{1}$ 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 universac 3 wagg;6stcca );l9vl gravitation.

  Compared to its mass on th6 5lrjgsjl,wz 4;krp 9e Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it -lsw cq3g9 k8pis on Earth. An object ofp 8qcg 3w9-lks mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's we lovg5+gh0udzxa rcd f12n.42ight

  A spaceship is traveling to the Moon. At what point is it beyo4 ;-cql .bsk1to(dwq3z r6mxl nd the pull of Earth' lr 3-doxt(4.lsmb1 qqwkz c6;s gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What1 d /ui m/ae,,h:tsylv is its centripetal acceleraehs/v, tluid a,:m1/ ytion?

  A hypothetical planet has a mass of halfm (bgxcl5c qr0ws :z83 that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Eargsbrc:z3x0qc (5 l8wmth?

  The acceleration of gravity on 0apo z u+xlxy 2+cipsf;24j7fthe Moon is one-sixth what it is on Earth. The radius of the Moon is iyx 4 fppz+a+ou x0c7s2l;2fjone-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surf1glc sz6*qvi+ ace gravity, but planet B has twice the radius of planet A. If planet A has mass m, whatq+ l6isvzcg1* is the mass of planet B?

  Two planets have the same surface gravity, d iyxw 3qn1u4 4*qxdj2boy.8h: ypv6ubut planet B has twice the mass of planey p :wdqv 1qy 2 .*xou4dnyhu8jx4i36bt A. If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a x-jlws/+f +jgch. fy0 spherical planet (mass M). Which expression gives this sa+f x.wych0 jj/fs- +lgtellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rota;x;z,j oqhuy9rza oysv-e 2;2 tes in the same orbit. Compare the two satellite's speedsv;e2 qjohs9;;-ur yxya,o z2z.

  A person is standing on a scale in an elevator accelerating dowf yia4ussdi +c;76gz 0nward. Compare the reasdf a+ 6zsi cyu4;0i7gding on the scale to the person's true weight.

  Who was the first person to realize that the planettq, sa3px(w2 ks move in elliptical paths around the 2x(t, aq3w skpSun?

  The speed of Halley's Comet, while traveling in i/tih* 9 sq 73ygkezm tf;oc0r)ts elliptical orbit around the Sun,o0i t )z7es 9kyq;3r/*mg ftch

  Let the average orbital radius of a planet be R. Let the orbital pek;,1n.habv aq m*w47 am5bf5 bqr;kptriod be T. What quantity is constant for all planets orbiting the p7k5,qvqb4tab1frw;n.m k* 5h am;abSun?

  A planet is discovered to orbit around a star in the galaxy Anf4j1qa ovd7dq pm. 1 ui/6,y9p1v xhdqdromeda, with the same orbital diameter as the Eart h y .q191o6 dpvjdqiq74dp/xvam1uf, h 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 is defined as one "astroec c;xm +rk;gfl/v )f;nomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid'm;;/kgx;lr cf) vcf+es average distance from the Sun?

State Kepler's laws.8xe5(dn ll(ak8 gmv:d

  List the four fundamental forces in nd g-u o/uj36x,: 8tq(cbk zmtoature.

  An object moves with a constj hc19sp 9k8-7 o*)xgmcvdoncant speed of 30 m/s on a circular track of radius 150 m. What is the accelera-ohj x8c1 97dp*mgc9 knc)vsotion of the object?

  The maximum speed arxuddaqv;riq.4xx5p*:t 6aea7t (gzd 9vy i-9 ound a level curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors4ev5a gpady-* 6:dv ra(9qx 9ixiu7.q;dtx t z remain unchanged.)

  What is the centripetal acceleration of a poims0/ ds3f0y jcnt on the perimeter of a bicycle whdf/0cs3sm j y0eel of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m *+rmupt jh di)pr3p57from the axis. What is )utd ipm +r*p35jhr 7pthe centripetal acceleration?

  How many revolutions pei3-fu thr gj+z35v, zbr minute must a circular, rotating space station of radius 1000 m rotate to produce an artificial gravit-hb tijf uzz,gr 335v+y of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes ayg0. r2s8wzh:kc gv )b bdt17dround a 13.7 m radius turn at 96.5 km/h. What is the centripetal fb :8dh).kwy t0 zgv1sb7rgcd 2orce on the motorcycle?

  A 0.50-kg mass is atrbx-t9e/5 qdb tached to the end of a 1.0-m string. The system is whirled b/95bret-qd x in a horizontal 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 verticae (x zjjtdy,lv4di /+u5qhj12 l circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The dljh dq(ivje /2t5j1 u+ zy,x4stone's speed at this point is given by

  A stone, of mass m, is attached toa- 0k hncrz0e-0lai y( 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 spelkcire0ya (n-- 0ah z0ed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when pullinzwr0 +y,fsdp)g out of +0frszy ,)wdp the dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outsidequ(4lelce xq8hdlu. sy99+5k vertical loop (in which the 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 his normal l( s.l u9lcxqd5 ye4h8+k9ueqweight. How fast is he going?

  The maximum force a pilot can stand is about seven times his weight. What is5j,epfnj jbu +l*b3 +x the minimum radius of curvature that a jup,+ x fnle+ *bjjj35bet 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 horirh 7lf/+m4t-r e 6npnxzontal curve 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 th/l6f4r -nep nxr7th m+e car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m7/ v8ix(pwz t.o(fnz0t 6kqul with a speed of 20 m/s. The centripe z/qxwt 7kn60p( f (8ui.lovtztal 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 speomb 7bw(twf3(c g* u,unps9 l0ed of 14 m/s. What must be the minimum coeffib3fs7 9lwp*w(ubnuo (,0t cgm cient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefficient oj0dwdx,8um mn05c ) ud(ok 4uvf frictio 4vjud kwnmd)u d58x0mco ,(u0n 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 Oldlx /2q/bka -yympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fri2 lk-/d/qbyxa ction.)

  A horizontal curve on a bobsled rug/9 ye *tmg9nin 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, obhjxv4e. 0 4orr/xv,yl7q9j banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banke-di)s2 g /ervzy*gay7d 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 uniformly in a hvt5o3c wk u5gw2zz 1a.orizontal circle of radius 5wuk52zc .w gzavt1o 30.500
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 t4 ryn1g /ll(uy aap+6ehe pit area, a race car accelerates at a uniform rate to a speed of 4gu6y1 y/(ap+elrla4 n 5 m/s in 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 of al p48pqa/upmbjv)1v f- bqw.: 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 forcxk(rx8zdg(iki ti62 5e on a 70-kg person standing on the Earth, due to g(8irk5idx6 xt2 z(ik the Moon? 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 masses is F. If thgj mz e v6wh;,ooi8c55e masses are moved to half of,wm j5o;6oighz5ve c8 their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from ther (u ax l lw-46f,rr0z.6x tvbi)wfb;s Earfi)fz0r 6xw 6v t4.asbx(,r bl;l-wurth will 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* hpyz ickq/g)8a s9e2 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 gy;h+z/z gr*b "space-walk" at a distance above the Earth equal to the radius o z*; zgr+/yghbf the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface zf)83 c2qbj4so hy .huss,4qi:lm op 1will the acceleration of gravi.o2 o:,lmfh4bis1uj qq z3c hy8p)4ssty be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distancderabmd0i8sf/72jox jh76:/sf pwr 2 e above its surface equal to 3 times the radius of Mars. The acceleration ofbjssjax 7o r0 i/2d6f7me/p2h8 fd:rw 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,a8*z ly 3s..kqfpf *mj the acceleration of gravity is j 8ka.lpm *yf*3zf .qs$32 \; m/s^2$. 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 rad0.*iq j x mn (pqad2nm(9pmot;ius r. If the object is raised to a height of 3r above the Earth's surface, what is its *m0x(pm;qnj.d (2piamn qot9 weight?

  By how many newtons does the weight of a 100-kg person change when a3iayz b-s1x(he goes from sea level to an altitude of 5000 m? (The mean radius of the Eartx3 1zisa(yb-a h is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a podeg)sx oe3j+ ,9b ztn:a-.fgoint 3r above the Earth's surface. fxt-, a9jed3oge z).ngsb+o: What is the satellite's weight?

  A spherically symmetric planet has four times the Earth) tn4l /ujoa4c's mass and twice its radius. If 4t/an)4l c ojua jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie oe8igj12;1sfkt t v38fm2ho jhn the same line, with the Earth between the Moon and ; oj2fj1fhe1h3tg8s8tm ik2 vthe 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 4z yfz7+x16+qx p* f3 luthlabis 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 lf*jujpm ,v2id/beu3 8dq 3k2xow circular orbit about the Earth (i.e., it just skims the surface of the Eart2pkvx m,3d j jbf*3q/e2ui ud8h). What is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a .diydtl; jot-,o e)q+ low circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean rad+t.qd edo) jito,;yl -ius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circu:xtdv125.g uq wjmsyk3 1+cl llar orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radmugy+ l:253 t1vdcxljqwk s1.ius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an l:m- wg. k7n(.6 pd e9xw 8stdqh 0raguii::bsorbital 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 - q )xuj-1(iiz8 zd;uztk(jeh 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 otpgum.z+isl0dg1 p* 9dac9q5rbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 g d udzp9*m+9sa5c 0qtlg p.1idays to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter iv3 ;c+0z sn gjyao6c5os $7.78 \times 10^{11} \; m$ 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 Sun once. What is the aver8l*tkm; c.4)kfa.krmqa+ym2 m5 l crdage distance from Jup4kt* . cqfya)k;m m.5lm alc2rk d8+mriter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)