Is it possible for an object moving with a constant speed to accksp+ j cjv9xru2mw*e+1ug)g,6q qj l5elerate? Explaiqjg5mc1j pv +u*g q)rju+,2l6k9 swexn.

  Consider a particle moving with ck1 8+ ba s4rwst+ w(9b*dgfumeoaiv3 *onstant speed such that its acceleration of constant magnitude is always perpendicular*w3 gr1v ase kfi+b (da*8sm4 btwuo+9 to its velocity.

  An object moves in a circular path at a constant speeej72ph :2upxs (vrw /td. Compare the direction of the object's velv7:xhu( s 2 /ptjrpe2wocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction p*pgjn v.:(m z/ea.gtxsu+a3of the acceleratig+3zue:tnx* g .ap / vmps(a.jon is

  Consider a particle moving with constant speed such that its acceler bq;pet*bc+ u3x+om (/k*f*awv(l i nnation of constant magnitude is always perpendicular to its velocity.;ab q*n b/+w(icvu3nt*elopk *x (m+f

  What type of acceleration does an objeeg) .+ynxass76;ecqi ct moving with constant speed in a circular path experience x c7 g.qnisa;)y6e+es?

  What force is needed to make mi wo ku+tlf23 4/2m ,wz)weaoan object move in a circle?

  When an object experiences uniform circular u..g-xqx 1mfkmotion, the direction of the net forcg .fqxxum-k1.e is

  A roller coaster car is on 4:m aqbx zk .xo:5kt,qh-mxb.a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with trackxbm:k5q,:b .o.zx x4khatmq- at the top 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 forms adqflqbuwg 5euo gp200 9,,wb7 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 value for dug5qw0p 9qw b,ug07fbe o l,2its speed at that point?

  A pilot executes a vertical dive then followsmm:,0-cbr/0 pq sd;gafqdh x7 a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force o-/gbh, dmr p0sqfq0;d xm:7acn 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 radi 3 ihe2tqpeu+ fam/z8-us $r$ 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 it gtc 1 *6pj-0x uw2vsxtboes around the same curve at half of the original speed. What is the centripetal force on thptx c20utsxvbj* w-1 6e 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 speed v. Then it goes aro j 7pjs;f(n59w3atzg1z :gode und a curve of radius 2r 51(f nst 7z w9g:odz;ajgep3j 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 curve of radius r with speed v. 7d3v(h(a;d; qxk ohio) hff6uk *at/ a If the road is frictionless due to ice, the car can still negq( 6xhufi o *;/vdo k;a)ahf3(kdt7ahotiate 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 abo5f; haxm;of wt1v : e+-b1 urg+on+are banked at the same angle, but one has xwfm1 o;fr+++ohu-: n;gbe avb5oa1t 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 safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled trac)**0 y esxu u0-ldm anh4. fut6rw3xsuk is not constant, but increases upward from the horizontal. Coming around s lwx usfxdmt y00r*uuh34e*n.a6)u -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 mo/6 86zmdofh i i0elppi kby5:*ving around a circular path to have both centripetal and tangential accelerationh:/z0lim6ifpoyk*di6ebp 5 8?

  The gravitational force between two objects isn. pxvutpd62 3y s4(whluo:0 k proportional to

  The gravitational force between two objeq6vxg-n-mlwluwoi 9:1-8f u yas 9)ugcts is inversely proportional to

  Two objects attract each other gravitationally. If the distance between their/beyn91q389dd xrk mvrf )q85rwzg1k centers is cut in half, the gravitatiov5mqyr 389br1 /9)8 rdfxqkzgw nedk1nal force

  Two objects, with ma kafge0 m)x+j)sses $m_{1}$ 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 massesz9+3j vflc6pz $m_{1}$ 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 gravi3j3 *7.d qq7t/f yunth2nehkae; kd(itation.

  Compared to its mass on the Earth, th9s (/ bxevv u8cw7/qnhe mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it;q s0 dsq,,u p1ux hsq78ohlf7 is on Earth. An object of 0u7,xhsu;s, sqq7o8q 1flhd pmass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rock;zy-h3hz7ug l et's weight

  A spaceship is traveling to the Moon. At what point is fknh82mp,lf mpj k cba9vw,jn: 45b;fw82 l5iit beyond the pull of Earth's bcf92lbw ,pvlfj;2nhnwka4f 85,i5mjm :k8 p gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What isee;i, z7:kzit its centripetal accezi :t;7kze,eileration?

  A hypothetical planet has a mass of half that of the Earth and a radius of jf xq-ce2t h()st6c +mt:u2u otwice that of the Earth. What is t)t+c:m2qf s2 chot(tx uje-u6he acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gs; 64sqe5 bqnvravity on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared tos ;5bevq4 nsq6 the Earth's?

  Two planets have the same surface grabt-s4d( e 5ocyvity, but planet B has twice the radius of planet A.4ebctyd( o5-s If planet A has mass m, what is the mass of planet B?

  Two planets have the saj wuur 0sthp8xdb2 q3 ,9oq9d;me surface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the raux j qs39r,bpd29hwtdq0 uo;8dius of planet B?

  Consider a small satellite moving in a circrxk i8/ 67yqlpular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital velocityqi/7pykr 8xl6 ?

  Satellite A has twice the mass of satellite B, and rotates in the samwbqju n.r+ 3)nu8er+j e orbit. Compare ther. u r)u+en+3wjqjn8 b two satellite's speeds.

  A person is standing on a scale in an elevator acceleratinoph8) i-tlo 8lg downward. Compare the reading on the scale to the person's true 8lti)- pol o8hweight.

  Who was the first person to realize that the planets move igim)og ,tc8e(j v 2zs:vyu5g(n elliptical paths around tvc :2gjio t(u)ygzm5(ves ,8ghe Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit arou)rv8 o-(ep5fp* z05bezd ctn ynd the Sune) fz( 5be *dtvz8p-oy5nr0p c,

  Let the average orbital radius of a planet be R. Let the orbdta 2 y g-pwxt1j *dhy)ay/(/yital period be T. What quantity is constant for all planets orbitingtaxdy ht yyj*d/g/(1w-a2y )p the Sun?

  A planet is discovered to orbit around a star in the galax80alwa pk2;tfrroixa4 vj k rs15,54ty Andromeda, with the samej;paaw1k8xa rorts f,5045v 2it4krl 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 period?

  The average distance from the Earthet(tpt 83x:ap to the Sun is defined as one "astronomical unit" a: te8t( pxtp3(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.lzou m8alyp))g biz 8p:,-.4bj dv* vh

  List the four fundameril b5aw8r2zmkvhfl )x4 6-o4g6m a9 sntal forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radiusdbceck .1-ejyvae8 ,/p lc0u0 150 m. What is the acceleration of the obcdeb 1lea0 -8jckpvc0, e./yuject?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum speyx 6tnrs ka) /o8 ebe6dm)6or,ed around a curve with twice the radius? (Assume all other factors remat )66xo se)adem k,6/or8nybrin unchanged.)

  What is the centripetal acceleration of a point on q6y m7y,b7is9ul kt:xthe perimeter of a bicycle wheel l: kmuiy7tq6x y, 7s9bof diameter 70 cm 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 from the a b(9 k4e2/+vaespxsmdgf5 r 1lxis. What is the centripetmvb s ldrf4e9g21+/xkae(s p5al acceleration?

  How many revolutions per minute must a circular, rotating space statibi;v r lg*y5f)on of radius 1000 m rotvbg)r; ly5if *ate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radstf5mvsg 8. 0wius turn at 96.5 km/h. What is the cenvswt.0sf 58mgtripetal force on the motorcycle?

  A 0.50-kg mass is attach:oc)pg*i ki4 sz2tix5ed to the end 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 max): c*ipz 5x kt2giois4imum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whdgo3 uei fqe ,5u0s*g5irled in a vertical circle of oe 3g5 5ud*iqfeugs0,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 point is given by

  A stone, of mass m, is attached to a strong string and wy,xm,k lb 1hl 7e*g fwunn +h4tkx-1p/hirled 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 weik x7 ,n x1 +huphbwm1 gly-nle*4k/ft,ght. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when ( bf;0y *+uluf omu,)cld(8m 9ujbqcz pulling out of fjc bqu zl(0+9 o;uymbcmu *)u(,l8f dthe dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside verap .m2sw7 e,batical loop (in 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 of his normal weight. How fast is he gobw2p7m,eaa. sing?

  The maximum force a pilot can stand is about sy/ / pty51itedeven times his weight. What is the minimum radiuset//iy 1 d5ypt of curvature that 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 rou b1*bk56yfo 9wo yuyj3nds 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 tires and each 9 yb5jy1 obufyw6* ko3road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. The c/u-v:xvh 1 l /;qrdnhqab4 3iyenn3-/4;h/rq :1aiyqh luvvd xb tripetal 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 speed of 14 m/s. o o toyx6t;l1fd*of9mlpo4.6 What must be the minimum coefficient 4 od ;x9 *mootplto.f661lyfoof 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 hyg gf:y:;bag0.p,uz ;de:zc level curve. The coefficient of friction betw.bhz;pz e;yyafu:g:d,gg:0 ceen 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 nego gn,im*t3 d9(bej-gs vtiate a 100-m radius turn at 35 m/s withoutmg bve-3n*jig9s,t( d skidding? (Ignore friction.)

  A horizontal curve on a bobsled run iszit 7 a)d 7av2kf:2xlb 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, 3)mra 8sqqj;1ij/oz z banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i0b)s k,0ub xezs 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 strinsm+ah8cv2st3 )a d +yyg is revolving uniformly in a horizontal circle of r+32sydtcm8av)h yas+ adius 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 unifodz/ iq/ fa qbygt.q949rm rate to a speed of 45 m/s in/ .btqd4ga9zi y q9qf/ 15 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 of a proton oflsb:x5ww3rhwmp;v (7i qmy22 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 ve)-bvlt//ygj lk,*nforce on a 70-kg person standing on the Earth, due to ll)n,k/yvg j/e tv*b-the 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 dce 5bmeiui., u glm;.dc93d; m cu. ;d,edlm.;gm 3biudi c5e9oved to half of their initial distance, what is the gravitational attractive force?

  For a spacecraft goingvr8b3my jalr.;5-gh06 prou 3 wo-j af from the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth j3h5 ;u-wopa6 .marr ob-08rfy3gvljcancel?
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 (4b h ust-qojfoi595c $7.4 \times 10^{22} \; kg$ 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 ahjz6onyr*n: wkuo 2q0 e*)u7r "space-walk" at a distance above the Earth equal to the radius of the Earth.un6* wr )7ozojy:hr0 un2*qke What is her acceleration due to gravity?

  The radius of the Earth is R. At w8wijzt sg3nh ys5 k;2,hat distance above the Earth's surface will the acceleration of gravi3s,5nty 8 ;2igwhzs kjty be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times tlno;)ocnx: 1)g umv8v he radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Marsvvn:g)uc8 1 ol);mn ox, is

  At a distance of 14000 km from some planet's center, the accelerationwof5hd* u6 c .2z.zhhf of gravityw2o*hchu f.f zdh5z6. is $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 f,ocq)9( aji jN on 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 qij ,9c afo)(jweight?

  By how many newtons does the weighth( z/r g(h,e5klky d8v f)pe2q of a 100-kg person change when he goes from sea level to an altitude of 50rfk5 g pe( y)z 2h/eh8k,lqdv(00 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. Av+,idb:1md hf )p yf,o satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satell hyd,ofvip,1d:mf+b) ite's weight?

  A spherically symmetric planet has four times the Earth's mass and 3f5obl8ael(/1 gvxlavo4 .wb 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 this planetvoa5a 8lw4v(llxbe f g3o/b1.?

  During a lunar eclipse, the Moon, Ex dw;;g-qwv8e (tf jby*gc/p 6arth, and Sun all lie on the same line, with the Earth betw-yj; bwggv8q /pe; c6x(*dtfween 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 transported to the Moo 4xf.shpjvqk :i-(uy2 n.
(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 loig7vn x/hd,l.p5xi6bc 6i h/ tw circular orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? 67h gxp dini.ith,v65c /b/lx (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 just ski,(nx j0k wi;j pc9,jwims the surface ,c0 9npjxi;,iww j kj(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 Earth.u, uw;5iwk 8no(.-qxsp* qyen It is observed to have a period of 89 min. What is the mass of the Enu(q8w -py ;is5unqe *x,wk.oarth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamel0*0)mco h26qmwxrx+ b( f flc)gip*ater 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 : 5yum6k6lvmuq-c3 bhplanet 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 ih0esqx5nayw/9b+n w8 n nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days qhw+ bnxw ns9/e 80ya5to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter i3t9 w3y;7owkvxh/ua db t:cp: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 Jupiter 12 years to orbit the Sun once. What is the lmwbikq2n5uf() /u.4wgc lo9 average distance from Jupiter to the Sun? (The distance from the Earth to the Suq)2uk w( i5bwo9glcmlf .4un/n is $1.5 \times 10^{11} \; m$.)