Is it possible for an object moving with a y3-iqyk:rn9nvv 1ve2 constant speed to accelerate? Explain. 3 rkvqe-inv1 :n9vyy2

  Consider a particle moving with constant speed such that m,qjp:7fo2n,:d zl tt its acceleration of conpn d q,2: tz:tj7,folmstant magnitude is always perpendicular to its velocity.

  An object moves in a circular path at a consj3xw2vm u* tg;tant speed. Compare the direction of the object'tw2vj3 ;gxu*m s velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the acc4-yfmq/ v1z n:sjw id/eleray/1d 4w mvq-i/fjns:ztion is

  Consider a particle moving with constant1m.g.pm/2 ep/nndm qh speed such that its acceleration of constant ma /nn /g.d1.pemq pmm2hgnitude is always perpendicular to its velocity.

  What type of acceleration does an objecsmi2v47e5f+lx4 y w vft moving with constant speed in a circular path experiencvsilf x f5w7myv 442+ee?

  What force is needed mn- k6+k.rktyto make an object move in a circle?

  When an object experience39oe cditlf)d fd0 oztrm)(85s uniform circular motion, the direction of the net force39cfir(l m 0d))8ttoo5 ddfze is

  A roller coaster car is on a tracs4c01zr dilvz *x5.ezp9j )q sk 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 miniqx1sl z5d) z9.rjc4i 0ps*zv emum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loop df8b8hi wwv /z1 .) bk;rllcrg99v1v i(radius = r) in the vertical plane. If the car is to just maintaiwh8lvd k1li9ifr9 / wvc)8;bzr gvb 1.n 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 until it is go j8vssu0h 1jnlp9 o*(ping straight up. Just as the plane is at its lowest1njs 89 ph0(jls*vopu 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 curvexew6.0n t v;.h+lm lse 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 gj8dzfb+f4,cr at a constant speed 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 for the second time, compared z,d4+c fgjb8f to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it: k18jkt7 bpu) zowg6t goes around a curve of radius 2r at speed 2v. What is the centripetal ou68) w:p1btgztj kk7force 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 yw c57cgy)mz, 7v2f ifv. If the road is frictionless due to 7,c7vy2yzg5mifw f )cice, 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 bobslvjy4)r; q f3hfed run are banked at the same angle, but one has twice the radius of the other. The safe speed (no fricti)3r 4f;hyfjv qon 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 track is not cons3w+ o7j *wm 7jpdrxlh)tant, but increases upward from the horizontal. Coming around a tw*wxm3hp)7 o7rl+j djurn, 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 circularw8*qcx3pq nfqud5x j- t ;(b rm1fsm,; path to have both centripetal and tangentiacds x (t q x15;*3ffrnqbup,qmjw8m; -l acceleration?

  The gravitational force between two objv5:cxitr, -7+6xwar td+; a*m dxvsem ects is proportional to

  The gravitational force between hi; by 13+2om vl)zbhltwo objects is inversely proportional to

  Two objects attract each other gravitationalsq-ni/ew*hjxf + t0m;y , 8gasw9f 9soly. If the distance between their centers is cut in half, the gravitationamfj*o/ s9s;, e8w 0-q if9xas+twngy hl force

  Two objects, with madx nf2ari*y0h+ m /5mmsses $m_{1}$ 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 masses nvuu4 1q1 vm ymy:pd;1$m_{1}$ 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 grafj s6cheu f r z rh6fy(/mrb1wa7gn5vg+6m; 51vitation.

  Compared to its mass on the Earth, ino21 7 tq0bmzdf r dzb3i41l.the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. ;+:blo /5ad9wr wpfcizi ;t; p An objectzp;p tl;ifwc:9r/5i+ wdb;oa of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sur mivt1krjknz:/ +gfnn2 ;o 9f7face, the rocket's weight

  A spaceship is traveling to the Moon. At what po0f7 ld, /bni4ewkf q7;sdy:cx.qgmv4int is it beyond the pull of Earth's gfk7bsxe; d mg4y .cdqi:wl0/7n4vqf,ravity?

  Suppose a satellite were orbiting the wgz)5- fiiv:kEarth just above the surface. What is its centripetal accelerat-i5 )gfzwi k:vion?

  A hypothetical planet has a mass of half that of the Eadr3 6l;k,x4b h f0:weohzfp1yrth 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 thkyzb fwrfe:h;xhld o31,p06 4e Earth?

  The acceleration of gravity on the +y rl8qvzvdc *ft1p /zf .ts9(Moon is one-sixth what it is on Earth. The r 9vfqdfrp z8t/(z*vc+y l1ts.adius 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 grza r6q 5u(p+phfok 7x8avity, but planet B has twice the radius of planet A. Ifokz86 xr +up 5p7hqaf( planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twin la8qv 9u6a75dv o+s:i 9,gearw z8uace the mass of planet A. If planet A has radius r, 8u7 69rio,u8qsa 5v gl9v : dawnaeza+what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) +qq0ji2glb6 dose;ppsq00 6g about a spherical planet (mass M). Which express g+0s6ql2 q 00esp6i;odbpqjgion gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. s*dvykmlb+m7i ugvnlqg ) q*9 n2j(gh9 8,z9u Compare the two2kmg yhujq9nmln8 7 9*b g( z lv,+9v)*sguiqd satellite's speeds.

  A person is standing on a scale in an elevator accej18 zqaqv,)amlerating downward. Compare t8qaz jv)mq, a1he reading on the scale to the person's true weight.

  Who was the first personfuf v9+ uwvv*vkh(smj 5+ 5.iz to realize that the planets move in elliptical paths around the Sun?*vjvw .fku+ (+55fvvzsu9 hmi

  The speed of Halley's Comet, while tm)pa.h o0rp 9t7*rjsf14uy x oraveling in its elliptical orbit around the S fy1rrt a0muo.oh 974p sxj*)pun,

  Let the average orbital radius of 2)z tz,d/jl-n xg6onda planet be R. Let the orbital period be T. What quantity is constant for all planets orbiting theol6 g)2dt/, jd-zzxn n Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, with thzzey ecigz4 l9 ;jsq4kr9+:g8e same orbz;ij99yrs cez gk8+z ql4:4 egital 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 period?

  The average distance from the Earth to the Sun is definww j35crdnmk(ilz:m+ ji ( tys11; hs3ed as one "astronomical unit" (AU). An asteroid orbits the Sun inc w3hzjd+3 ys:mm trl(5;w1jn(isi1k one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.hqn4ei8,eas6c+r,zmv )u) di

  List the four fundamental forces in namf wy r4vb *u-/tyr8e :6cs0jwture.

  An object moves with a constant speed of 30 m/s on a circularj8i;*) akbtyjqc ,0l u0r 1w elfi1*gt track of radius 150 m. What is the acj8ttqc1 0ilr)u; g ,1keb*ay fl*ijw0celeration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is 95k zqod*x vo *96nvdvm ulkd .-0g8xqthe maximum speed around a curve with twice the radius? (Assume all other fact gqxnodkvvxqzd8ou*5l 9d09m*-v6 k.ors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle nqiqbr*1j4uc h6xb o tg2 0-)pwheel of diameter 70 cm when the06c h4rtxp2)bb 1oq n-q gj*iu bike is moving 8.0 m/s?

  A point on a wheel rotating a)n yqxpboohd /46)9w jt 5.00 rev/s is located 0.200 m from the axis. What is the centripeyj/ 9nw))4po xho d6bqtal acceleration?

  How many revolutions per minute musje;x 2 xp0xy/lq6qn3y t a circular, rotating space station of radius 1000 m rotate to produce an artificial gravity j/xyqpx yq 6x;32n0 elof $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radx x:auy+d j tlsoljo3uo--w; ,ty/ /d2ius turn at 96.5 kxoa-o;uy2 lujdy:st-j+w3 dlt/x , o/ m/h. What is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whirlwc*s u 21 (egr8uu:uhned in a horizontal circular path. If the u2h nu*s(1u8e wuc:grmaximum 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 vertical tw0y b1a6 -pwkcircle 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 this wt10- ya6p bkwpoint is given by

  A stone, of mass m, is attached to a strong string a,4g+kr6riy )6t-aw6jldo lf and whirled in a vertical circle of radius r. At the exw if 6j6ay+r l),k6glo4- trdaact 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 pulling outdh z7xt+w6rp 6mqx8 *e of the dive. What is the radius of w *d+mhzx76px8qer 6tcurvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which thonw jbd5*sxj 3u*+w6b 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-h35 *njs+bxdwb u jwo*6alf of his normal weight. How fast is he going?

  The maximum force a pilot can stand is a+swf hp (vz93tbout seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling z v (h93wp+stfout of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius ho425e-q*ah.l6id-uk oruh xzy rizontal 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 the ca-z. x4e-k5ra* uoyil 2d6hhqur's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m wt:0:gclqqn g87e1 dguith a speed of 20 m/s. The centripetal force providng :eclqgug0718q:dt ed by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flatb bhm498xywr0 curve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between 804xwbh myrb9the 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 w+wjv6l 3 ivrbq-+ mi(of friction 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? w-+qwvbmi i6(v+rjl3

  What minimum banking angle is required for an Olympic bobi9 t/mrr,w63ph+vr jcs,h ka4oo jb.6 sled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fr,9ji3kr4s+c , tovr.mrp/6hwob 6h ajiction.)

  A horizontal curve on a bobsswiu y0 jh3ms4x5+b5 wao2k rhz5p9w4 led 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 m, banked at a8 b o9c*j .rsaq /dpjpz g/xu/5)ay*ten angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked m9zg g a;xp fqefg.g;lb2,/8wat $45^{\circ}$. 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 unifxwq-pzk+j 6 fq/0,dh zormly in a horizontal circle pw jzd ,6 hkx/-zqqf+0of 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 accelerates at a uniform rapqczj7 czd88 or09p 2qte to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (onl j0cc97pr qpz28o dzq8y 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 con8(xola l443axhnf+cwsists 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 forcmb-d13njqo: ge on a 70-kg person standing on the Earth, due to the Moon? The mas gqd3:j- mobn1s 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 betwvm at4 /*1l9mxa16xwh p,nafneen two masses is F. If the masses are moved to half of their initial distance, what is the gravitational att*/fw6hv9x1xt1n4a,lpa mn maractive force?

  For a spacecraft going fro l n1hrk4nr2d9m the Earth toward the Sun, at what distance from the Earth will thhkrnrnd4291l e 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 i+x70j)b qysw nll3c:fz0m1 lf 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-wad3ty2op3/. ; .nwnl8az rn dfilk" at a distance above the Earth equal to the radius of the Earth. What 8rnp;d2nan3 ytio3wdz f./ .lis her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surjf gx2y ent3-9 mp343nd6 sdxoface will thegyx63s nf dd2xt4en3-pm9jo3 acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 t35eu6cls0m izimes the radius of Mars. 0csizm 5u3 l6eThe acceleration of 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, the acceleration of gravinwq 8:nn6bvijm 4s,m9ty ivqws49 n bnj6: ,8mmnis $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N o7 /o8 invjk ty,-;4vl;yt kmqen the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its weigik4m/y ,ot8q-k ejvvl 7tn;;yht?

  By how many newtons do ryo:e m/frdp8 r-f5+ic92cgies the weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Earth isc/8e i2mr+g 5y9- fr:r ipfcod $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r abo;nu if e()w5ozve the Earth's surface. What is t 5ewu( f;n)ziohe satellite's weight?

  A spherically symmetric planet has four times the Earth'sxqh8 r8ta0s uj /1ws--mz /nce mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Ew qth-/xe18um0r/ s- a8zjncsarth, 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 linqrn,6i 4jwq tn4 ,yuw1e, with the Erwy qinu 1qw6t, n4j,4arth between 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 0h7; qbkzzn7 fergx4floo/. w5fy3f 2gfj1 e8is 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 low circular orbit about the Earth (ignt; o iip;+)gm)3s e 5j:thgl.e., it just skims the surface of the Earth). What is t; 5 nigs+p:o tg)3ejmh)it;l ghe speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the :+zwqo s w;z tqyn, j:*fffmc1476lyiEarth (i.e., it just skims the surfacef1zst7iq: on:jqyw w; 6z f4+cfy* l,m 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 kms6lwyk4 y+ kf: above the surface of the Earth. It is observed to have a period of 89 min. What is the mass k+:fl6k ywys4 of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Ju x 8;njm.7.swpdqkeg+a-f e* dpiter, has an orbital 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 rdz ;;h6b c6z sgm00*e(aqm fjdv*d)xJupiter 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 ne;9tlxm m u+;uuarly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orb um9mu+xlu; t;it. How long does it take moon B to complete an orbit?

  The planet Jupiter is g93y1y9exmrw $7.78 \times 10^{11} \; m$ 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 ozf (akk q,5oc*lj+cej(, 1pdurbit the Sun once. What is the average distanc(*l pcjoa(d,u k,5kcq j+fz e1e from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)