Is it possible for an object movgoch2 )alae(n) ;yv 3xing with a constant speed to accelerate? Explai nx)vhyc(a;2oe)g 3a ln.

  Consider a particle moving with constant 0 d96(gd +u7qz:.bp: yllyr2hxgu yaispeed such that its acceleration of con0u:q2idgyhxy 7+arlgz. b(pl 6y :9udstant magnitude is always perpendicular to its velocity.

  An object moves in a circy p 5em3eks)3wezp69y ular path at a constant speed. Compare the direction of the object's velocity and acm e95)6e33ykpsype zwceleration vectors.

  When an object experiences uniform circular motij;.3 7k 9kzpv:bznd x 97t:spn.byxtxon, the direction of the acceleration.px:xbjk9s ;x7t yzk tzd9b37: v.pn n is

  Consider a particle moving with constant spee)q ryrryk+.c5 .;qz+ii6flvvd such that its acceleration of constant magnit 6crril).yi5+; kf.rv qqyz+v ude is always perpendicular to its velocity.

  What type of acceleration does an object moving with cons6putig n-0q 5ptant speed in a circular path experiencun6p0 5pg-tqie?

  What force is needed to make an 4zmgk)r 2 3u+bbyih1 dobject move in a circle?

  When an object experiences uniform circular motion, the direction821nzehj20 jhm( rtsn of the net force inh(hje1 rn08t2 2sjmzs

  A roller coaster car is o7vv9kj (8 cfy mjf5 z1) 2 cwdw*35styg9jomnsn a track that forms a circular loop in the 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 accelert3v2 m1mcv57gsjjf5y*cnd (wjk98o)s w y f9z ation at this point?

  A roller coaster car (mass = M) is on a track that f2wre;c kw, j c1z,ksv/orms a circular loop (radius = r) in evwc k1c; ,2zrk,wsj/ 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 point?

  A pilot executes a vertical dive then follows a semi-circular arc(f nemg9wby oitnz0n;o0:k/* xkp:h7 until it is going straight up. Just as the:tonok(7h xy 9b*0 mwgp;fi/enn:kz0 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 xo)sh6)pr4a o6 iyb0q . ei,upof 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 const;v x *bsz-t t6uc2cp1tant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as x1bp;t6tv cz2*c-t usit 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 sa:p jkmo kb*s( n5uu(3peed v. Then it goes around a curve of radius 2r at speej5:o*3 kk ( ampsu(bnud 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 bankhy e y m3x)w 5)0uanq/60nbnozed curve of radius r with speed v. If the roau0 )n /)yw60o3 x5yamnnzheqbd 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 magnitude to

  Two horizontal curves on a bobsled run are b;;da; j tjmer.8 qbnqifds91) anked at the same angle, but one has twice the radius of the other. The safe speed (no frictej qjns)9ma8;f;tqi . 1br dd;ion 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 turzquys)44-qf o n on the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobs- q)yzsfuqo4 4led 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 ,s/ ll o0+ mv;zryn5yl4uprr ;both centripetal and tangential accelerat;u yrynl+m 4rv ps5;r0/,zollion?

  The gravitational force between two objects is proportional2i )knuq 9j6j av1j(za to

  The gravitational force between two objects is inverselvmvt 0 pw/uk(5y proportional to

  Two objects attract each other gravitationally. If the distance between thni8;p 7a5ttq yeir centers is cut in half, the ntqta;yp758 i gravitational force

  Two objects, with mass ai(kze68 *dbj(rh8cigv9 r)c6yy , zwes $m_{1}$ 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 massesbnvlyy,v t32o7h +g4 .2hubx i $m_{1}$ 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 ga*o 716ltd2en eaqfh2um9 u.yravitation.

  Compared to its mass on theuuo: z,e7-z b10ywlsf Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-s23 f4,k s(ai h76 fv/gia6h wso9viumzixth what it is on Earth. An object uis,f4i36/2s(g 76a vhvao wmh zikf 9of 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 weight-xd4mbvvp3 n p4gq7f ;

  A spaceship is traveling05/z k,zz bavd to the Moon. At what point is it beyond the pull of Earth's gravik 05b/,zzvad zty?

  Suppose a satellite were orbiting the Earth just above the surface. What is m(ys1(t mweqm)0 ma b.its cas wm(mb.0 em1)(myqtentripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius -8rdpt nz;t.8gg 8ezy of twice that of the Earth ;-tt8zg8z.rpnyge8 d. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity yzs,3eauzrs1t:ol4 y r ;-w9x5j g0ekon the Moon is one-sixth what it is on Earth. The radiugr aj zsy,lo:e19y5z3ru; tekws x4 -0s of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the radius of movsui*d g73jpqbjb)(6rtvq g6;u+h3bi p:+ planet A. If planet A has mai 7v pgj)g*t3bo qh rup6uqv 6dib++( m:;bs3jss m, what is the mass of planet B?

  Two planets have the same sc *og i*w:nniegbxz6.7-7u zvurface gravity, but planet B has twice the mass of planet A. If pln6 o czuxgb-i 7.v*gi:ze*7wnanet A has radius r, what is the radius of planet B?

  Consider a small sated:c 1cr sl5o93b k68qp)gm ppullite moving in a circular orbit (radius r) about a spherical plp59l6 g:3cpdqmcorku1bp8 )sanet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in tpwjmas.zz( muo)(:tn3m /: a ihe same orbit. Compare ma z3z:m:u(o m/)(saw ji.tpnthe two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Cex 3a9repc+1a ompare the r+ exra ea3cp91eading on the scale to the person's true weight.

  Who was the first person to realize that :zhv;8hy -u liqxzpe8;h* *ih1q y+cmthe planets move in elliptical paths aro;i+:xp* quczmh1zi8le h*y;vq - h8yhund the Sun?

  The speed of Halley's Comet, whi i1k4xwad**ba le traveling in its elliptical orbit around the Sunaw d*xa*ik41 b,

  Let the average orbital rax/3*a/nw.o)jfb*rpzrag;vs dius of a planet be R. Let the orbital period be T. What quantity is constant for all plas) f*x r/;v.zwo */jpra3bnga nets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, qkl kj70fm0t8+xe pn.with 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, compared to the Earth's orbital per8k. elqpt7 0nxkm +j0fiod?

  The average distancecf5lba t h+*i,zd 2j2y from the Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distancej b+c25td,z2*ahi y fl from the Sun?

State Kepler's laws.kb/r ree2u7yp 12vyi/

  List the four fundamental forces in nature. a)mngfv98u r-k-iw g,

  An object moves with a constant speed of 30 m/s on a circulkc.2lbk (a y*yar track of radius 150 m. What is the acceleration of the object?l.a( y kkbc2*y

  The maximum speed around a level curve is 30.0 km/h. What is the mm tgb 6+uo;4l1rprnlgow s y)77/(,* j kfxgfoaximum speed arou+oxgfo)6gyr 7n/*;1gb4f 7p tuwl m jk,(oslrnd a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal azc u; n)l )pv) bq khu* nq/0nl01byogq04va/xcceleration of a point on the perimeter of a bicycle wheel ofnq) nvp;/xahl) y1 o0gcql4v0n z*u bk)qb u0/ diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.is 7rar//lnv800 rev/s is located 0.200 m from the axis. What is the cenvr// r7ail sn8tripetal acceleration?

  How many revolutions per minute must a circs4fwffi q0fag(*-:o hi .zxj 0ular, rotating space station of radius 1000 m rotate to produce an artifw h0fo*ffj0faq-. (: izxs4g iicial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius tu rtql- y)cdroca85f 86rn at 96.5 km/h. What is the centripetal force on the motor8tc8a 56)qdf-yr olcrcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The syste* kwtp8 vn9+0*mv sc0 jzcoi4zm is whirled in a horizontal c*0 si nk 4ocv8*0 +9tpjvzczwmircular 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 verz . m5; wo7zxodeoo9u45nsq;o tical 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 5;z;wuoso oone9 dzox.74m5q this point is given by

  A stone, of mass m, is attached to a strong stvkfyo6*r r1, u09spplring 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. pop,yk06 v*r9ul1srfThe stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acou*u g,e wf vks(1(vjol/ 7o*sceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plv1 ouo,soflw*/*sk jg7ev u((ane is flying?

  A pilot makes an outside vertixg54me34 x:0 v 4rrjqcr b grvrgs77l6cal loop (in which the center of the loop is beneath him) of radius 3200 mrcv4 6egrr75bg x3 s0x7gj4r4q:mvr l . 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 going?

  The maximum force a pilot can stand is about seven times hiv,zn9cpp;*0 +,du+dz bl mvgi s weight. What is the minimum radius of curvature that a jet plane's pilot,lzp v; *pvgdc,m ,n0i+9dbu+ z 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 radiu:.c8cn)nni 1bcox xn; s horizontal 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 betwee incnc);x oxb1n:c .n8n the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 hkl09zwengtx+kl3vb ys0v3 9 1b4 e,um with a speed of 20 m/s. The centripetal force provided by fri9+ulhlgv30e z3ek ktw1xs940b vb,nyction 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 of zy h2 cfc26h q88qxm0r14 m/s. What must be the minimum coefficient oq6fm22 yz0qh h 88cxrcf 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. 2 yh:3ldqwn,p2p ecz: The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the cuew:nq ypzc 2lh:,2d3p rve if the car is to stay on the road?

  What minimum banking angle is reqby)hdj h pbzdqqn(1i+gsa ngh5;2 +5 (uired for an Olympic bobsled to negotiate a 100-m radius turn zh+qh(na 2ihp(;y5q gb+b5djg s1)n dat 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked azpiz38,vs l 9(l+ tvvm3opk0e t 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, banked p:6fgfj8lp1 bn 8mp nv(8a5x uat an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bapm*0c7ffi-gr nked 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 st2m vse6 u5,m kiydgnt4 mdwt n1ee/(rpv1z+,0 ring is revolving uniformly in a horizontal circldep/v+,(w1mmgn0yeen2ts1z6dir5u 4 kv,t me 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 area, a race car aspr8w+u8q2 rl )jdb wai0a,d 9ccelerates 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 value in the blanks) s l8uaw9dw, d+j)0rq8rbpa i2
(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 cont5b,lel,hww) sists of 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 jdps d*va+6y3on the Earth, due to the Moon? The mas* 6vyddps +a3js 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 the mx v1r;*f *hk/ xjeae ivk8vj17,s- qlmasses are moved to half of their initial distance, what iis7qv jj f*vm8el,h 1x k-ae/*1kxr;vs the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distd- ,3kaa*brfpr4n)p tance from the Earth will the gravitational forces due to the Sun and the Earta4- t pap r,br)kdf3n*h 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 is 6y,s/q7 bwhxmb 8ktj5 ehn,a2$7.4 \times 10^{22} \; kg$ 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 a3/k:njt y2w (jqq gf-for a "space-walk" at a distance above the Earth equal to the radius of the Earth. What is her accelerat jk (f:qaynjqt- 3g2/wion due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface wil s 4izzn:h-mgjol2z (/l the acceleratizzzol/(m2njh:- sg 4ion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfac e2jc2m-rnb4ie equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to thembe4rn ic-22j acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the accelerati8*bf3pt( /n9kbs rswd on of gravity i(tsw f/98s p3nb*kdb rs $32 \; m/s^2$. 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 p0b)./ hlfifc Earth has radius r. If the object is raised to .lfhfbc/ip0)a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight ou em50a .ugva1f a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of tha0 uv ae.1mu5ge Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite okacpece8k5yb)1y6/ (jsl-e t g8, jkjf mass 100 kg is at a point 3r above the Earth's surface. What is the satele(sck-8aeybt86 jkg lj ,pjey1 k5/) clite's weight?

  A spherically symmetric planet has foutyf-qpwv0a z8x,v 4aapv. 4c+r times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N4ata4fp vp a,-yvvx cwq8+0.z 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 Suiuysxg y:6p8 ,,6wi zqn all lie on the same line, with the Earth ,iq wys gy:,6xip68z ubetween 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 transir8 g8wsg3s7 lported 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 low circular orbit about the me0hbb+z bo3 hu11m b,.bh9c rEarth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius ofhbmuorbm.e+ 1b 01hz9 bb,3 hc the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about ra oju,n1w) lw2 kkc+-the Earth (i.e., it just skims the surface of the Earth).rak c1)-2ulkj ,+wnow 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,,vk5d /x/(p qup eccl of the Earth. It is observed to have a period ofke vdxlcu p,(//cp5q, 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, has an orbitalyvu.(n,r m+s j-d l2tg8ajpb 2 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 wiy)n 156a9um yupn- p xud/gt7 qvy tnhu2(y-*yth 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 orbitg8*k0szehgv2m-,fqo s. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 208-g0 kehg*omsz 2v,qf days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is a3i0rq+(wnz +h6qh(bzdg0lq$7.78 \times 10^{11} \; m$ 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 txejkb.07-s-bop*. y/ gc ,qk ukaun9she Sun once. What is the average dyou0-. a,sg esq/nku*9.kxkb -b pj c7istance from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)