Is it possible for an object moving with a constant spee()e1b d5- *6kvx bmji -jhqvgsd to accelerate? Explainsj1vbx)k m -gd6(i ebq *v5hj-.

  Consider a particle moving with constant speed such that its acceleration of ,b(v/i hcug0s constant magnitude 0i ,(sbch vgu/is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. )bndw3u ,w pt9r5f(g q Compare the direction of the object's velocity and acceleration n5r3 9,f(bdu)gtpw wq vectors.

  When an object experiences uniform circular mot (+, mfyuu;1 dhup9dheion, the direction of the acceleratipd+y1h,uude u(m9;hf on is

  Consider a particle moving with constant speed such that its accelen b5/n(8 i:l+ orylslgration of constant magnitude is alwr o8i:bny lgl/5n(l +says perpendicular to its velocity.

  What type of acceleration does an objectkhi f0yl.f 0(p moving with constant speed in a circular pal0p0kfyh f .i(th experience?

  What force is needed to make an objespqu n7xmc 9t6c18qd(ct move in a circle?

  When an object experiences uniform circular motion, the direction of the net f x)r0eeu3fw. oorce iere0 o )3uxwf.s

  A roller coaster car is on a track that forms a circular loop bn .b52u(tnrf in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what isftb (.5un 2bnr the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a trac3neox/s5ntq6; vd m.3 eeaav4 gxj-o9k that forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the/eod3-egevjq3x9; av5mn 6 tosan x4. 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 unt ts0n*(/ av:zxugr satg,9g5wil it is going straight up. Just as th xg :n*,at5gw0azs9rs/(gv ute 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 cu0d7+btwtr*6h gz gvc 8rve 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 r at a xi c.451i g1ep skevf4mu.hx4constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the4x1u1 cx m4ei hv i5f.s4epkg. 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 sbv f lxr73zaf,p9wb:3peed v. Then it goes around a curve of radius 2r at speed 2bwrf3x9,v3 faz7b :pl v. 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 curve p.rt4wpaa1e 3 of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontalppe 1t 3ra4w.a component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a (ex:i.,zni b+kv4uuf bobsled run are banked at the same angle, but one has twice the radius of the other. The s,u.( : uv+xifek4i nbzafe 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 theq4:a hglb.jx7iz7tvdd 2w;z9z (vtd- Olympic bobsled track 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 tur. tzbvzqj 7g 7dt( hv9az:-wd;ld2x4in. Why do they do this?

  Is it possible for an object moving around a circular path to have both centrut4lw i+rb 1)bipetal and tangential at)l b 4biw+1urcceleration?

  The gravitational force between two x nefy5x- im8/e0t+pfobjects is proportional to

  The gravitational force between tw9 3nscbef+jk) o objects is inversely proportional to

  Two objects attract each other gravitata(jf26 lyhdf0 -0hq4 y* hfokvionally. If the distance between their centers is cut in half, the gravitationalh0fdyvqfo(2jf- 6k0h4 y* lah force

  Two objects, with massesb 1y*eh2- gqtanm98r csx+r) b $m_{1}$ 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 massjb08 ,kjrh0gn es $m_{1}$ 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 grav9b. 19wrkv1izhmz xp5itation.

  Compared to its mass on the Earth, the mass of an object on the Moon nrae 0(qk -5vlghr-m4xki/j*is

  The acceleration of gr4wr2vixic t(u ulyz,)m sm4/5 avity on the Moon is one-sixth what it is on Earth. An objecc2)wvu ir/,m 4li5ms(t4 uxy zt of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from tp h94 jjkuldis8gt ,wb0u 0:)zhe Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. zc+v j-3axxy j.e)j;cAt what point is it beyond the pull of Eaxx3;j c+z)c va-j. jyerth's gravity?

  Suppose a satellite were6hs;+ c-8 kkxmmia -ni orbiting the Earth just above the surface. What is its centripetal acceleratihn- +8;s-a kmxmkiic 6on?

  A hypothetical planet has a mass of half that of the Earth and a radius onkvrv ipzd h 5(z0x009f twice that of the Eart5(nd 0zihzrkvp90xv 0h. 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 on the Moon is one-sixth whklls-9,hxcp 8+ *d.b 0lddckvat it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth'sl8ldkdb,cdpxlvc . +h0k s9*-?

  Two planets have the same surface gravicoy5/ mk7h7fq/ py r)dty, but planet B has twice the radius of planet A. If planet A has mass m, what/7) cy/k5 qdmhoyfp7r is the mass of planet B?

  Two planets have the same surface gravity, but planet a5zw y1w .4gkdB has twice the mass of planet A a 51dygz.wkw4. If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circuw r e3kzb .u0.qw8w0nhlar orbit (radius r) about a sphericak.u3zrnwe08bww 0q h. l planet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the salpwxuwm/kw9 9l6h. ;oxl,g y)me orbit. Compare the two satellite ; uwg9/lplmy,o)h lxxww.k6 9's speeds.

  A person is standing on a scale in an elevator accelerating downward. Co xp4tcyn .8-fompare the reading c- pnf48ot.xyon the scale to the person's true weight.

  Who was the first person tvy;erlh l59- ayoy3 *to realize that the planets move in elliptical paths around h;*5e9-yto3la lyv rythe Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit amrltwas3c 4 /1round the Sa3t4w s mr/1clun,

  Let the average orbital radius of a planet be R. Let the orbital period bec 7s tnsq3b9j by b2t3hk1t tb9ax:o5b;,za-c T. What quantibjbs ca ;ct1btb279y,q9z5oa3 nt3s:b-th kxty is constant for all planets orbiting the Sun?

  A planet is discovered to orbitcs q9u.058 j-hhbx enk around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of ourjbu5n98h.exk 0hq - cs 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 "astr(t,td5rh/6f b f-md lg gp re(i.zp63zonomical unit" (AU). An asteroid orbi,5- 6(frb 6m3gt rd.gze/(fp hpzi ltdts the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.oe;aq;fy9;eu

  List the four fundamental forces dtke:qvnifuaw3 5fb, 6z*bd/4. (w zv in nature.

  An object moves with a constant speed of 30 m/s on a circular track of 6w9nd7 8qhal4ydseq l ka/u.3radius 150 m. k9d /7qhl6 n l4ysudea83a.wq What is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maxn mbn6k.lv 8lnb7uyv:eyz0f (.0h)da0 mtrw- imum speed around a curve with twice the r.0:-ryf6nyz(7.tl8w0 blkn0 mem ndbvhuv a) adius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point ks4dt mc5 n2:con the perimeter of a bicycle wheel of diameter 70 cm when the bike is moving 8.0 nms2kc:t 45cd m/s?

  A point on a wheel rotating at 5.00 rev/s is lo8co .5 y8olfwtcated 0.200 m from the axis. What is the centripetatf5y 8owo8. lcl acceleration?

  How many revolutions pe)r )6,: zu/ozodcb)l e, vkynwr minute must a circular, rotating space station of radius 1000 m rotate to produce an artificial gravity ore),) 6ucl): zzkn wdby,/ov of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes arous-hd 7pg6g2g:(qwyrrx4 c un :nd a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the mogp h 67uw::dr4(r qxcg-2 sgnytorcycle?

  A 0.50-kg mass is attached to theveoc0ik u +gh/mo4o)v c7-gdvxi 3 l50 end of a 1.0-m string. The system is whirled in a horizontal circular path. 3g-ulgo7 d+oimc4 /ov 0 h0vci x)ev5k 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 vl wvkgx56f y,07(9 ilqz1 stcaertical circle of radius r. At the exact top of the path the tension in the string is9y5l,7z fs(cvwtqlik 601xga 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 strxz3c g0 cg nipu3rt4( u1h)u4aing and whirled in a vertical circle of radius r. At the exact bottom of thecgt4a 3huruicpx3g1 )n4u( 0z 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 pulcb:l;a;0 :p0yyyzwyaling out of t0 yay;yal:b p;y0zc:w he dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (inf :tji q..pyx9r,e ;igb5o7gn 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 f.n q g,9.gpoi:r btx;7ei5yjof his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times his weigh4tdq b;33i)wso+yrcac a8k 3kt. What is the minimum radius of curvature that a jet plane's pilot, p;+b r3ack8 3dctk 3sq4i)owayulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rour (ge(hht39mands an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 mrm9te h(ha (3g? (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 with6(vbl .4-ww)wvk+kq we az(lo a speed of 20 m/s. The centripetal force provided by friction ik4alvkw -wqbz)e(w. (v6wo+l s $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of8i3g* u 5natez85wp7 vv9wyot radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the ro tp ayw5 uow8gnv8* 95e7zivt3ad for the car to make the turn?

  A car is moving with a constant speed v around a level cur 6oz:fv1acmxy7(; k ayve. The coefficient of friction betweeak:7 zy ( mva;x6yfo1cn 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 to negotiate a 100 mc )kv8c-tg-/g r(bmi-m radius turn at 35 m/s without skidding? (Ignore frictikb r cg-it/m-c)mg (v8on.)

  A horizontal curve on a bobsled run is banked at a uile8 8bs.a5w,g ;mbk ul/ cu.$45^{\circ}$ 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 r-igxg3czzw+ ;-n 2ew fadius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b 3mwo(qbd 9ji.0;uhx+:at no banked 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 unifo9zd9 .h,i 4v 1dy1n/l ltlihabrmly in a horizontal circle of radius 0.5dnv.9/ld14t ia,liy bhhlz9100
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 ca3 yh83 7suzf(yyip qk/r accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circulaihyus ( ypzk7 qy/f383r 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 consist3xde;fl ,6 7 cc.xfkur(nl3rf um99bps 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 odxo swj6l1 q7* jsk19dn the Earth, due to the Moon? The mas9ws x d s11ljkjqo*7d6s 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 forceoqm gxyr cj0yo);22g4 between two masses is F. If the masses are moved to half of their initial distance, what is the gravitational attractive forro j4og 2qmy y0x;c2)gce?

  For a spacecraft going from the Earth toward t)tpbc5() gcmyhe Sun, at what distance from the Earth c)m b(gp5)cy twill 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 i+cd-y prne6 6fs $7.4 \times 10^{22} \; kg$ 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 uxn*9dw:2/h0 fu66 v sx wbpnv"space-walk" at a distance above the Earth equal to the radius of the Earth. What is her accelerativ n us6n* 60 vuxd/px:9fwhwb2on due to gravity?

  The radius of the Earth is R. At what distance above the Earth's lpb 1u* njs0gk* b81pjsurface will the acceleration o80s1p** njlbpu1kbjg f gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfghl(m, 4l+eme8c;x4 lba28a : batkwkace equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to teak +m, ace;k la484b lhg: b2x(8twmlhe acceleration of gravity on the surface of Mars, is

  At a distance of 14000 nc.7 fx)uq/4w2gh p*dks0ug f all d-fs/x9g6km from some planet's center, the acceleration of gravity is dlxff nhf2xg/ )s7ksg lg9a *-w u.q4pc6ud/0$32 \; m/s^2$. 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 radiu*1bf3 sbyfo5v, agj3js r. If the object is raised to a height of 3r above f3,g vb5bojy fsja *13the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes from qg97y en0u ykw kp)-/ca7d/c.wczc9v sea level to an altitude of 5000 m? .caq nwkcce9 9v- kd/7p/gc )7yyz0 wu(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 above theg+8 cdo*w js/g Earth's surface. What is the sateog+*cw 8d j/sgllite's weight?

  A spherically symmetric planet has four times the Earth's mazy s)lez-nc * b7xvmm9aas/ 3*uxd-w1ss 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 thmln- 13dy 7m/)e sz xaxu*9-svzwbc*ais planet?

  During a lunar eclipse, the Mop;8 yl( f+ptxk)wn b bfm5+gz3on, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. Thz yp+n fb(8pk3f)mx g5l ;+twbe 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 trafiy1i/ fl0gs/ nsported 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 thea y g(*ktf/7mr Earth (i.e., it just skims the surface of the Earth). What is the speed of th*gmayr f7k/ (te satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Eae x+5n: *zrhsxb y3p7;jkonq9 rth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around qxxyzo;p+57*:nbsnerk h9 3jthe 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 is 8t0tk 7bnj4n*ujifwl+kt/ .0fw bj4a observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the +/u0 ttk8jjnkl wnwj4 i47.b ab0f *ftEarth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamejm+7 /y,k0,2t k mdpb*is oblbter 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 r)6dh ujlpp4 ;wuee0kbt8x+:cadius 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 orbits. Moon A has orbital radius rlup ja u96ir);, and moonrli) a9ujp ;6u B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 8v;( .lnmlir f3vgc8s$7.78 \times 10^{11} \; m$ 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 Sux;v:mkm g3d5zn once. What is the average distance from Jupiter to the Sun? (The distanc x: vz5kmmg3d;e from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)