Is it possible for an object moving with a constant5oonf(;/l1xjt1ui e)q ok1o b speed to accelerate? Explainbou1jq1n5fl/iok)o ( t;o e1 x.

  Consider a particle moving with constant speed such that its -bxlyck :2)fh acceleration of constant magnitude is always perpendicul h) yb2fclkx-:ar to its velocity.

  An object moves in a circular path at a constant speed. Compare the directi7 loa +uf6ypf9on of the object's vel6uya97+lp o ffocity and acceleration vectors.

  When an object experiences uniform circular motion, the dir;rkm hs e4a (twzz+3p9qdz( -dection of the acceleration iazem-(;9sdw+ p 4tz3(rzk h qds

  Consider a particle moving i,53bkc7b5g gijk0 xw with constant speed such that its acceleration of constant ma0cgijik 5 wk3bxg7b 5,gnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with congftm/m7* -cen r p85ysz nmav od40f39stant speed in a circular path experi0/yn 5 m3 seg nz p*aft89vodm-4mrcf7ence?

  What force is needed to make an objecwk1x+9 q f m;3gp;jywrt move in a circle?

  When an object experiencm;te eln ba::9es uniform circular motion, the direction of the net force is9eb:am ;nt: el

  A roller coaster car is;d)s:; 2* t: iiejyrw -gxhlpl on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the to xyrw:lhtei*lspdi j ;:-2 g;)p of the loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = rjwdbk7 ftf39. ex89oM) 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 track at the top of the loop, what is the minimum xt d93ew jf .kbr8fo79value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular ae h+j1z-yre0jrc until it is going straight up. Just as the plane is at its lowest point, thezehjey1 0r-j + 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 o7y0qzs- h5esq.rbi1 flx w- 9cf 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 al agcoifj/,(mz* 7t,mg l6rv 7iujh.yw8s**ot a constant speed v. Then it goes around the same curve at half of*tv7s u rgao6oyg.mh,li7 ,8jm* *izlw /f(cj the original 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 ;sr+wmh.3:fovyno,5 jxqg4i at a constant speed v. Then it goes around a curve 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?iyj45o ;h,fgsmo.wr :3v+n xq

  A car of mass m goes around a banked curve of radius r with speed v. Ifkmu7o2*.uj ;lxn :a aadc)k6q 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 r 7aqn) ukoam djlac.2u:*6 xk;oad is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, buaev1 ga m 4vg )fke:.g+75zudvt one has tweg .vf gadkv1au ez v457gm:+)ice 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 safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant, butdb*ia0llrcb;x6 h f-u:k9t +w increases upward from the h09 twk - lf*ac :dibbxhr6u;+lorizontal. Coming around a turn, 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 p5uoxcr w2 vik*vp5j(. ath to have both centripetal and tangential acceleration .r2jop xw5k5c*u vv(i?

  The gravitational force between two objects is proportional t0.hdo 7r7dhp7da3 lweo

  The gravitational force between two objects is i kccy ftjs9xtek9 (3(b, )/hm.m2nvk cnversely proportional to

  Two objects attract each oth;/9s3j/yf +zmqxx xhq 4xd3eo er gravitationally. If the distance between their centers izfm9x+qxxqo4d 3x// ;3jsh eys cut in half, the gravitational force

  Two objects, with map8 ekh*s0ar 7nsses $m_{1}$ 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 massg2d12deeo tsx j;v0a7es $m_{1}$ 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 univew;)9zr thm a8d54lvfirsal gravitation.

  Compared to its mass u -itk 32y9wimon the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is6x5o,xsf9+x)s z yp. uu6sdfj one-sixth what it is on Earth. An obu6jx ,6 5xdso.+f)pfx sy zsu9ject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, thhz(/azr)/y demhe rnk*1b :2-e cp8a 7ircnh+e rocket's weight

  A spaceship is traveling tq v a 6 8lm6mirryf.j(q9)sc.co the Moon. At what point is it beyond the pull of Eafr.rjvsliqy8. 6mam(q)9 c6c rth's gravity?

  Suppose a satellite were orbitinwkyw g,m;rv q(1ar61 fg the Earth just above the surface. What is its centripet1g ;1q v (mwwkfrr,6ayal acceleration?

  A hypothetical planet has a m w2,nx upfb)q*ass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the plaxq *wub)fp2 ,nnet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth wha/ l)c6gtqst5 mt it is on Earth. The radius of the t m5q/6tgs)lc 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 tw tbs*nsi(de agbd2n cwo7 kjt 7(dv .w2.-j,*sice the radius of planet A. If planet A has mass m, what is the mass of plane2tnss(gb2,jnk* *id 77 twds.evw( bd j-c .oat B?

  Two planets have the same surface gravity, but planet B has twice the mass of t49p n/, jufe9. jgppkku800yo rtdl/ planet A. If planet A has radius r, what is the radius of p,kpgj u9yu0/d4tfjonp.e098 plr t/ k lanet B?

  Consider a small sateymqaf- *-yb28 q+vx nlllite moving in a circular orbit (radius r) about a spherical planet (masb m*8af+y -vlqqxy2-ns M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rot1oym g,3fmzi .yd1j0: h hrjj.ates in the same orbit. Compare the two satelliyjm1.1hzjjmhg0 rd ,o3.:iyfte's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compare tf(okx, hig6 2b w, v*gxck.wid-v4(dwhe reading on the ic., bxo*6w d,(kxfk2ivwdhgv4w g(- scale to the person's true weight.

  Who was the first person to realize that the planetsulqi1n(eh6) tg8ym;y move in elliptical paths around th;6lt)h n(mygeq81 uyie Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around the hso05c 0lb+2ohvq:fc Su +0vlhch q0 :sfcboo25n,

  Let the average orbital radius of a planet be R. Let the orbital peri)wjj8 2di:dgiouax --ov0c5 nod be T. What quantity is constant for all planets orbitiwi)8vogu 5 i 0add2jjco--xn:ng the Sun?

  A planet is discovered to orbit around a star in th8- s+ajzrq7y ge galaxy Andromeda, with the same orbital q7gjr+zsa 8y-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 1yu2 5pb5s s :ws.tnicis defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third ofsy u:.5ns1ic5bps 2tw a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.va8ntw:z(s4 i

  List the four fundamental)wdcyo1 m )m,l forces in nature.

  An object moves with a constant speed of 30)i q*,wn vm+ih m/s on a circular track of radius 150 m. q *ihmw,n)iv+ What is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. Whaus bh-ypl m:.1ew9vj(qi dl-5t is the maximum speed ibewqu ds(h m-:pj 5l.-1vyl 9around a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perc4cy( : 4sgju,hal a:dimeter of a bicycle wheel of diameter 70 cm when the4ay g:,d auh4:lc(jsc bike is moving 8.0 m/s?

  A point on a wheel rot:0aek 05zbv*pe:kw yg9+yvmo ating at 5.00 rev/s is located 0.200 m from the axis. What is the centripetal ak+9 epmz5*gwb 0o v:k: e0yvyacceleration?

  How many revolutions per minute must a ckk+i qx /04lqs1o: lbl/fac 5fircular, rotating space station of radius 1000 m rotate to ob/xq 05f: qaf+llkslc/k i14produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goesjrvqyj :z(r/6ypv 99t around a 13.7 m radius turn at 96.5 km/h. What is the rtj: /6 rypyvjq9 zv9(centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end o45v4nppozc. rqb7c )3frmg 1 lf a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that t7g.oc) mflrpzc 3 rpv4 q145nbhe 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 vertica0 w* 8ebq/xaf0y a8sgtl circle of radgaq00wbaye/*8x8 stf ius 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 point is given by

  A stone, of mass m, is attached to a stmu4blb)q * u3a( ylnop/ph+:zr 7oga*rong string and whirled in a vertical circle of radius r. At the exact bottoqa(prboypb z *u*gnl+ h4:alu37om)/ m 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 experiencebzn,(:-sz heps an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flyi-zzh: , s(benpng?

  A pilot makes an outside vertical loop (in which the center of the loop is be 2ec;sx3. m(plvi+trh/drl t) neath 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 we s+etl;m)cl./r v3hr2d(xtipight. How fast is he going?

  The maximum force a pilot can stani- 378mqyhrse.qqjv0w+9mb vd is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can t7imq9-qb0vj emy.q3 svr 8+hw olerate at a speed of 250 m/s?

  A car traveling 20 m/s r b5 3d gk6 ,mfvhvm)p,hxc+d,tounds 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 m? (Assume the same coefficient of friction between the car's tirefkdv h g,m,tx dh6+m5,v3pb)c s and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 2iixlqad79 mt: 0b:u,u0 m/s. The centripetal force provided by friction is mia90l ,:dxqb:ut i u7$1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curtdo7klzyg1 g18p mk/,eu :h/l c+;rvrve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction betwk l: rt/o c1gehzdlv+m;1 8,rp/g7kyueen the tires and the road for the car to make the turn?

  A car is moving with a constan/)+fyic* x od;-b8i bosqbq a)h63m dlt speed v around a level curve. The coefficient 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 o8) i/h6 mxyf lbsoq*;ad)ib-3 +odbq cn the road?

  What minimum banking angle is required for an Olympic bobsnq1hlt v i5+i8led to negotiate a 100-m radius turn at 35 m/s withhvt 81nlii+ 5qout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked souzki )0gle)6bw +o +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 q7hgo 61pcckfkz/2d ;of radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at0 etnmmtj/r+) $45^{\circ}$. 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 horizontz,7ec56rfrvkm4;n+rip4 5 cgyk394ijyb qpcal circle of radimq7c+zb6g r,4jk 5kvi5; iny9rr34fy4ep cp c us 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 ct mowz- prg8 mb06hj4b5;s(rthe pit area, a race car accelerates 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 nb;(5gz ts-mjw60 p8ohcmrrb 4umerical 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 o,dj) zy/1g42d+iplt wcz e, odf 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 on the Earth, due tod2ihv. moko,/c8p8 r r th, 828vmc/.dorrp ki hoe 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 the masses are ,wpm zij; ip**p91 sejmoved* m1i*;z pwp,p jjsi9e to half of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from thqu)8j4ajz(b drwtem qa2ww5 14z51zbe Earth will the gravitational forces due to the Sun and bwtze 842)waq 4jbr z(wj51 q1dmu5azthe 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 Moonoa kui+tsj;udmy -fj56v, 66v 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 "sqh ay0p)hzj hrnae+w2g y99)-8knj1 cpace-walk" at a distance above the Earth equal to the radius of the Earth. What is her acceleration y8j hr-h2je)z 0 na+ qk 9wc)yh91nagpdue to gravity?

  The radius of the Earth is R. At what distance above thu-8p9vsxfiuh1 6s rsp691aq fe Earth's surface will the acceleration of grav axs18rvssfp9q1h u69u6-f p iity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its5j ggr9p8ydg* surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleratio9ggj y5rd8*gpn of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acce:2wkg ; ljvmlb4w 4uj(nd:; ajleration of gravity isalkjd4; nwu:( 4 2bvgjw;lm :j $32 \; m/s^2$. 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 Ear+ty qq/ ir,o cx,iv s;-d9iv)pth has radius r. If the objeccsq-9vovdy +;), xtpq ir/ii,t is raised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person 6qvc b mqae(na+0y:oy);ha7c eu 6ze) change when he goes from se6mebna6q0 y)7ca; hq):a+c z( vyoee ua level to an altitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. zzmzw4o2s,f85n.4 k rz9k v rjA satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the saw 8s,o29 r5v. jzz4knzzk4mrftellite's weight?

  A spherically symmetric planet has four times the Earth's mass and zn- 3efxa ,pj5twice its radiu-35zaxefp, nj s. If a 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, aa v (i,wt26w:tonh c7end Sun all lie on the same line, with the Earth b2:c oiew,7ha(6nvt wtetween 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 ioa des 0vm gx*))e4yh9xir80w(tx 1cms 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 swmrc)1 (l87zv ph-z3ogfi1 babout the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The)z s z-p318 fmwi(7gvb lhco1r mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbi.ukh.: nwn -a7.g9abym nwo-kt about the Earth (i.e., it just skims the surface of the Earth).k-7gb:auy9. mn.k n w ho.naw- 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 surfa.l,(;/atdx z7cxgz*, efpgqx ce of the Earth. It is observed togf,, gde/x* 7 pcaxqz.zlxt; ( have a period of 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 Jupi;-w /d pfhsi3yf q,;a6qmp (iqter, 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 Jupiter orbits the plan* bp*pya1 mm)l y0k)ayet 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 planao2:ba e7uz2 qet in nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20a:a27 2qzobue days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter ishlth fzv( ) f7 riek-i5.t b;7zln6h1z $7.78 \times 10^{11} \; m$ 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 average5n xy4h2tt+ me distance from Jupiter to the Sun? (The distance from the Earxthet +mn 452yth to the Sun is $1.5 \times 10^{11} \; m$.)