Is it possible for an object movil1ho,* 1eanvy8h;t ;hmeb s4vng with a constant speed to accelerate? Explain.oh 4hla e1vb8nhe *vt;s,;m1y

  Consider a particle moving with constant speedn c;9donf.ia0 such that its acceleration of constant magnitude is always perpendicular to its velo0 nd9;afnc.iocity.

  An object moves in a circular path at a constant speed. Co/xvovv.-ys -y( vge*h mpare the direction of the object's velocity and acceleratioys.v(hv-v-vy eg*/ox n vectors.

  When an object experiences uniform circular motion, the direction of the accely *3x5n-tdsi9fjww) beratio y3t)n*sd-xfbi 9 wwj5n is

  Consider a particle moving with constant speed such that4ru h mqsjpl mf,e6-j; 7 kw(c-*/qqis its acceleration of constant magnitude is always perpendjhj e kmpqq6i*c7/ sr--;,lw(uf4qs micular to its velocity.

  What type of acceleration does an object moving with constan1qsbv2tko n w7ej 7k9-t speed in a circular path experienkq1772sk tvo-wb 9n ejce?

  What force is needed to make an object move in a(f l*;di-i+ p6n f2hikahk522 gv vwkw circle?

  When an object experigonvm8 u y z38)0-zolkences uniform circular motion, the direction of the net force isgzoz m3 y8)-kvnu8o l0

  A roller coaster car is on a track that forms a circular ljvby3w ,chew ikg g8f))2pq5+oop in the vertical plane. If the car is to just maintain contact with track at the topw8k5g bj)y+w2v,) p 3eiqfhcg 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 that forml4 pkui; h6sl tb/32lxs a circular loop (radius = r) in the vertical plane. If the cai x /; bsk4h2ltu6llp3r is to just maintain contact 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-circ i1 s v34kcpify.dig6;dv2su- ular arc until it is going straight up. Just as the plane is at its lowest point, the force o1pc2g.id viyi;sdufs k463v -n 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 radius tp227ib xv)g wkoen6)dud:4o $r$ 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. Then ,p( uktattbf,f8c, -f it goes around the same curve at half of the originfb ,8f-cu, tpfat(tk,al 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 a3fu270stpqa at a constant speed v. Then it goes around a curve of radi3tf2 qasap 7u0us 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 cu1rriy (vuik0 ilw03 a:rve of radius r with speed v. If the road is frictionlesr 1uwr(l3 i0:i0 akvyis 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 to

  Two horizontal curves on a bobsled run.nvbb4ir hr v2)mh97 o are 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 s mrvnhi2)o9b b4rv7h.afe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled traj) )vz t2cd /t,-wqoouck is not constant, but increases upward from the horizontal. Coming around a turncd2)jq,ouz-)t wvo t/ , 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 )yg qqnb,im*cvk jpu4 /,-4g-djmt.n centripetal and tangentialpq --ncq)gm*/gvtjud,y b,m 4n4 ki .j acceleration?

  The gravitational force between two objects is proportrgv;k8 *l/ +d5ud6)lzk7xg 4bengtw vional to

  The gravitational force between two objects is inversely proportiont6(z*:nuxmm v. a t,fdal to

  Two objects attract each other gravitationally. If the distance betweenv(acvuk:m9:,a*e hs o their centers is cu(vahe c:,v 9asomuk:*t in half, the gravitational force

  Two objects, with masses :p*2th 6liwdg$m_{1}$ 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 masseswk8getj0zc3/oh0 bc* 5w +gt c $m_{1}$ 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 of7;fcb/zac5e isw; f0w xq42hv universal gravitation.

  Compared to its mass on the Earth, the mtahv s3z: 19x-s+/qtqt4kas p ass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it.+ thsqu;m.n m is on Earth. An object .hn.sm q+;mutof 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+k )dpus l7qfx ds p51;j*rs4yight

  A spaceship is traveling to the Moon. At what point is it beyond the pkgkb6h;h3e6;)fatrf ull of Earthr kk h636fabhf;ge t);'s gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What is xsu n1; l;l42j pyj3ieits cent;j;31 nl jlpeixs42uy ripetal acceleration?

  A hypothetical planet has a mass of half thatb6j5 p+yhra5njs. j-j 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, tsj-jpn+j56byj a . 5rhhe acceleration due to gravity at the Earth?

  The acceleration of gravitur hn9bgd)q- / 66 ol:v-xybbby on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fournb/-9 rl :-q uv6)gbx6bhbydoth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravitk*p0 iq x9 2d6vrrta31: n z6ipfpi(jdy, but planet B has twice the radius of planet A. If planet A has mass mi irpz *r0n9p kd2vj616(:if 3xqt pad, what is the mass of planet B?

  Two planets have the same s/0vn7e 4zmpvcl/hp j7 urface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of pla7 c0lv//z 4mevnpph j7net B?

  Consider a small satellite moving in a circular orbit (radius r) a 4z.4 d+yxknksbout a spherical planet (mass M). Whikn.+4xk4 zsd ych expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rogf 9p,*qlggha08n onx-v 0c1d tates in the same orbit. Compare the t8fdxg o-*0ghgv nnl,0 q1a9pcwo satellite's speeds.

  A person is standing on a scale in an elevator acceleratin yp,i k xn5v51j+facf,g downward. Compare the reading on the scale to the+ p,xkcfjnfa,51iyv5 person's true weight.

  Who was the first person to realize that the planets move in elliptical pa25eg+s(* fvlm w -6jqw lzon4tths arg6nz*jf m tll-vw (2+ o4es5wqound the Sun?

  The speed of Halley's Comet, while traveling in its 92w tjs 2ujz:6* hbobnfjm(,selliptical orbit around the Sun,ftujz6som2 b w2,( sj*b :9hjn

  Let the average orbital radius of a planet be 1vcp7 k,zauhexb( gj p(f3sq;:5 8sscR. Let the orbital period be T. What quantity is constant for all g b;8s1s u:jsh(ef7cp,q(v 5kx3pazc planets orbiting the Sun?

  A planet is discovered to orbit around c;0s.9wovl;o 50r d.f jrzbewa star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that strs 9owdz;5;rc. .0 0vefjow blar 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 4 sd2hryl sc1*the Sun is defined as one "astronomical un21csy 4slh rd*it" (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.s;ym/ bwb- vq42fe 0ua

  List the four fundamental forces in na(5da r8d:3a0nhsx mtoture.

  An object moves with a constant sp*ub ru)g)1yz .*cuur eeed of 30 m/s on a circular track of radius 150 m. What isug.ubz 1))r* uryce u* the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. Whsn 2v8 /p3m1n8tgo xprk 4tr4sat is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchanged.mts4p8 2r so/31vtxprn4gkn8 )

  What is the centripetal acceleration of a point on the perm2x rbko94im(imeter of a bicycle wheel of diameter 70 c9(bixrm42o m km 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 fromaagzs62f;y o 9bb8*r n the axis. What is the centripetal accel6 abro2;nsb9 y 8zafg*eration?

  How many revolutions ; l:b/dpzw1 micey81mopu5 ex (mp;-rper minute must a circular, rotating space station of radius 1000 m rotate to produce an artif pi5- c;m8ez p:mxp ml1dr1;/wybueo(icial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes w5*q,js c wur/t4it+laround a 13.7 m radius turn at 96.5 km/h. What is the cu s t+c54 wqj*rtl/,wientripetal force on the motorcycle?

  A 0.50-kg mass is attached to the envdqk +:vo0td -d of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed o-kv ddq:o0 v+tf the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a a+f fi zwms2)ti a +25dg/ctsm7ie d68vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The stone's speed at c7gmt a8+efsit 2s+dw zf2m5 ad i6i/)this point is given by

  A stone, of mass m, is attached tv vpz+*7pzl1no a strong string and whirled in a vertical circle of radius r. At p*l vn 1v7p+zzthe 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 accele 4s)cdul elnq;g:0/bw ration of 4g when pulling out of t/u;l:b0 4d necqlws )ghe dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loy h+e l bo h,n4d9.vb+,mljf9hop 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 fast is he goingh hjyh mo9db ,lb+.4,+9vnlfe?

  The maximum force a pilot can stand is about seven times his weight. What is thnr+ h -/my/vca5 lfb8m,xmqby, 27njye minimum radius of curvature tyl5q,nnay /m78cb xbm, h-mf2j +/vyrhat 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 rmw-q wxcn2i0h7o-;htires on the v; 2hmhwqo ci07x--n rwerge of slipping. How fast can this car round a second 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. The dp;.fmp9 - ys1c+yoomcentripet9ypoosyfm -+1 .mp c;dal 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 speoh;a nv3sh1 t6t f1jr3ed of 14 m/s. What must be the minimum coefficient of fric;3hos1n6 h3fa rtv 1jttion between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a l5 s qut)bw*axlok-,5f2tt i(wevel curve. The coefficient of friction between the tires and the road is 0.40. What is t takltos5,fut-2*xwqb i5w() he minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an O/ngp/3i09n 2o cx notzy z(,iqlympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore f/ qiy ni op/g,n(029 zot3znxcriction.)

  A horizontal curve on a bobsledfmtx;q kof*:d y-/g2j 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 pmtonm0zk8j.g6 1:a um, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked aacf /a* 8epq0kqb 5,uft $45^{\circ}$. 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 oow+fs8b (i+bp xcbfb(2s 5f7 ubs -pu;f a string is revolving uniformly in a horizontal circle of radius 0.50 x8us7+b bc fwpb+s(2ipbu5s;o-fb(f0
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 uniform ratsacvi nq77; *pe to a speed of 45 m/s in 15npsi*7vc7a ;q 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 kb.)e;x,k dflof 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 fork.8fkk2 l,f r tacb+s4y0l4 03tx;kbj+pfx wece on a 70-kg person standing on the Earth, due to the Moon? The mass of thc+lwl jf.bt0rskb y,84a+p tfx ;0f43 xk k2eke 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 /ep s.fim,n,5k/z6 qbs8yzrq-f9 qahF. If the masses are moved to half of their initial distance, 6s qfe/ih9 bp 8mz5/ z,sf.yrnqq, ak-what is the gravitational attractive force?

  For a spacecraft going from the hym t qtk /50u4m9bt3(n7uszl./dgvv Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth canceld4vl0h ybs7g9 53/mtmk u/nzuvqt(.t?
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 (p2yja :pn8unis $7.4 \times 10^{22} \; kg$ 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 "spai6f s s rf/6(ryj:c9byce-walk" at a distance above the Earth equal to the radius of the Earth. What is her acceleration r 69y :fir6(/ ssfbjcydue to gravity?

  The radius of the Earth is R. At what distance above the Ear,9ni)k47x zl-6qfdt)i ex3t f hxj0lgth's surface will the acdtxx)n-, 739it f6l)4izgj q 0fklxehceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above inr . m6uux9t)tts 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 Marunt).6x utm9rs, is

  At a distance of 14000 km from sor 4-).fwv7t k8 eo(1ih mldytcme planet's center, the acceleration of gravity iri kw-t( d8ehfy1.c7lvmt)o4 s $32 \; m/s^2$. 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. T eab4i7z;b z)nhe Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its nzi)a74bz b; eweight?

  By how many newtons does the weight of a 100-kg persona4q8:0qch. . gdmaiuv change when he goes from sea levd m.8hcaigaq4:v q 0.uel 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 pdwu qd 7ia/ l 53,.f r1j4yf2fb/nxzxabove the Earth's surface. What is tz n3bx2,j7xpa/ iwlu1 qdryf fd/ f.45he satellite's weight?

  A spherically symmetric planet has four times the Earth's mas8ow glka:m)hq. da ;cbmc09h 7s and twice its radius. If a jar of peanut butter weighs 1g80:c;.7ochl 9a w kh am)qmbd2 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 on the same line, with r85p1 ob:bbggthe Earth between the Moon and the Sun. The Moon has a massgprbb g:18 bo5 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 th3;v 8d3dcw1.a pvky/6f j -d umvd)hxze 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 t57 j/ mk44x)9 kxa bksteslf*khe Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? kkblf)sktemx j s54 749*kx /a(The 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 jf55w(wd6w ddoz*vhen bil251 ust skims the suwbw*l1d2v6on 55hz w(d5ie fdrface 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 the Earthw u,;wfhyr56w vx a-0y. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean rawwvywh y0-6,r; afxu5 dius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamec u .6qs0asb1cter 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 radius of 40uzybuq/ ishw*h bv /m2t3v.$422 \times 10^{3} \; km$ 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 or 8jecuuf/v1+tbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to completeefc+t /8uujv 1 one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter i3i/nqnv;e i6 :s3sx6mfh ei,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 Jupiterqvy0bx,cr(b 1tf k813b z-9ps,txlqn 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from s9n( qx0qc kyt pb -,fxbr1,tv 3zl18bthe Earth to the Sun is $1.5 \times 10^{11} \; m$.)