Is it possible for an objo 3pt o*-*cvd rvk9seg(bf3:vect moving with a constant speed to accelerate? Explainf 9vv*tpbc(rv*-kdg: e 3 oo3s.

  Consider a particle moving with c bty+o.5o8d 4:m 2aa/j ixj66gynoa svonstant speed such that its acceleration of constant magnitude is always perpendicular to itno 4b.yv g8/:x 6y5am+ 2aaisojt ojd6s velocity.

  An object moves in a circular path at a constant * ixg:uh6aa0z l. i5ohspeed. Compare the direction of the object's velocity andhia*hi6l au:x.50 ogz acceleration vectors.

  When an object experiences uniform circular motion, the direction of ymzs 9)d( 1ge6vri 6 zu,7yh:lsa2svzthe acceleration 7dg(u21 rm9ya: )s6zzls6ihv,sy z v eis

  Consider a particle moving with constant speed such that its acceler-b9. q5 x+p,euwdibrqm7 8ffwr0w, tlation of constant magnitude is always perpendicuwtr8,q wwbfu -l i.dmrp5be9+7x qf,0lar to its velocity.

  What type of acceleration does an object mos nk at5)2tf hh64nbb8ving with constant speed in a circular path experienn htbhb65t 24kfas) 8nce?

  What force is needed to make an object move in a cik flm.9hznwb1nu-e+, rcle?

  When an object experiences uniform circular min* esw6k b n)qc+:4bnoa2q/r otion, the direction of the net force iw2 +cko6n/a )q4rnbesn :bq i*s

  A roller coaster car is on a track that forms a circular loop in u.cz /4 avcr - gahy-cc0*e,bfthe 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 accel/ vcacebyahgc c0 ,-*ruf4 -z.eration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loom( rdya s ;wb*t:dxecr4r /lg+/ohyava:, 93tp (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of the loop, what aemr: (ys a 9,gd+ /vc;tral3/:dtr 4yx*hobwis the minimum value for its speed at that point?

  A pilot executes a verticjolnb : tftz g mf203q5jf6m:9al dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the ffb to63fz ftj2: m:lg5 jqmn90orce 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 of ra 6y*ivrjhw6s8 dius $r$ 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 ivm uthu/xdg 4+- 4k;(bsnd l(constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on tg4 ((btkv h d-;lx udm4u/nsi+he 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 cons1 rhy8m --knjytant 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 arnryj 8h --ky1mound the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with speed v. If+;r;qwc st6g n 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 road is equal in magnitude;r cqgs ;n+tw6 to

  Two horizontal curves on a bobsled run are bankrr jvcfn7a;)*: s j,rsed at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius curve r )an: ;s rjfvj*rc,s7is v. What is the safe speed on the larger radius curve?

  The banking angle in p 6wzg5q-x)4)k zlfvia turn on the 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 turn. Why-w)fqxg5 z pk i4z6v)l do they do this?

  Is it possible for an object movim2:u9s vdsdrhfr g .2ejk/ 58ing around a circular path to have both centripetal andm skrv9g/: 2su ddf.er5 2hi8j tangential acceleration?

  The gravitational force between two objects is proporti+mdsa2hmhrbh4s -4 hgvt:g 4,onal to

  The gravitational force between two ,5eml :ncrx l7objects is inversely proportional to

  Two objects attract each other gravitationally. If i pzi- (; wvf1ny0br:welx;4dthe distance between their centers is cut in half, the gr;pv bixzwr0f 4(l de;-n :wy1iavitational force

  Two objects, with massik+ o ikjaog285g *m (8jwj.uses $m_{1}$ 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 mau 5; twwrf3-:sbdt2k fsses $m_{1}$ 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 gravitation. 7mzcq be7,o vp-6/efb 2ayzk.

  Compared to its mass on the Earth, tdwz vye7h:5/a:s- qo rhe mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is tl xdwj5u8 e+th3 +k9 3qdqel6on Earth. An object ofedhux +9+q t 33kj8l5qwtlde 6 mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the hhp9 t. oe*7 ;9ahyhherocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond t uhv0 ywm:e,blr4gf-8ya6 ,mthe pull of Earth's gravvamf:r et,ym6bhlg,-80u y w4ity?

  Suppose a satellite were orbiting the Earth just above the surface. What is ky q1)p-4s, jz1x6h bqcg ,gmjits centripkg q 61 pcj,1-hbmg )yjxq,z4setal acceleration?

  A hypothetical planet has a mass of h6)og,q3qc-i k m(lxt palf that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planeik (lmp,gq3qt co6x )-t in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what+li2s( u80sx) )f yqxx kitaj3 it is on Earth. The radius xiax0+yftil23xsukq8 sj )( )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 m8- :awzddwf ;sist 7,B has twice the radius of planet A. If planet A has mass m, what is the mass otf7,s w -iw; z8:asddmf planet B?

  Two planets have the same surface gravit1id.; -ax+jh;gnt *4 xadpocty, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius n; x*;tdcpo t a.hj+4-daixg1of planet B?

  Consider a small satellite moving in a circular orbit (radius r) at .soshpjn/mbog 3 v t7;f.59mbout a spherical planet (ma bsfsnp;j.o5v gtht/3om.m 79 ss M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. 4h4wsov)g5:pdfa x( 1 1 xqfkt Compare the two satellite's sqd x54 )fftah1k:v1(spgw4 xo peeds.

  A person is standing on a scale in an elevator accelerating downward. pp4o 8*gv khas z(dq8.Compare the reading on the scale to the person's true wei8a (p qdhv*so8.kzg4 pght.

  Who was the first person to realize that the planets move c u6c ew1w68cjin elliptical paths around the Sun? 8ccuwcwej661

  The speed of Halley's Comet, while traveling in its elliptical orbit around the i; b38psuyws4b12 v gl:q6 zf5f7lxhiSu b52 vqislix:1386b; y s4 flhwzf7gupn,

  Let the average orbital radius of a planet be R. Let the orbit8b:v4t0 sr2 spc s(f2of(kiib w+p/wval period be T. What quantity is cvf 2w:spoib/ 8sfc( 2swt+(v4 0k pirbonstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a s.nq -vw 2o qxpxdj0/g7tar in the galaxy Andromeda, 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, c/.7o-qp jg dn20vqxxwompared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as one "astronom*k. sbtf7q*t dical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the astqdsfk* *t .7bteroid's average distance from the Sun?

State Kepler's laws.n t2poek+66o o1p1wmeid xk5k(zz) *t

  List the four fundam,qi3l w(k0cs/ jd .octental forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of ra*qv ku m id*;.ek-olk6dius 150 m. What is the aco6eq ik. *k mu-dv*kl;celeration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum speb o38zuvxxf,( 9g vgr-ed afrxgx(8ob zg,-v9v 3uround a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the peri e+r.*jewvsww,b*b,:x 1xdtqmeter of a bicycle wheel of diameter 70 ceq vetwdxr*s.*:b+w,xwj1 , bm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 r m51v1xzf9wz r;iorp7gj+;n xev/s is located 0.200 m from the axis. What is the centripetal accele+j5zrgixo7 z1 ;vnr9xmf p1 ;wration?

  How many revolutions per minute must azj4:.d ud an868ipbqp circular, rotating space station of radius 1000 m rotate to produce an artificial gravity ofzpi 8p46n8ddj :abq.u $9.80 \; m/s^2$?

  A motorcycle has a mass of 250) 2/:qkubb8n m7r sfgt kg. It goes around a 13.7 m radius turn at 96.5 km/hbn kbsu/mt fgq ):278r. 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 isgqjv;p a/ d5 ,gldtgamc+,kf9 i-f.2y whirled in a horizontal circular path. mpg gc,f 5lia.,gkjd2aq+; tyvf9-d/ 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 vert1r wgd0:r f*mkical 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 this poi dg1fmrr*:k w0nt is given by

  A stone, of mass m, is j,jnw cjhr 8 /z2xrs9dy ; p2ld2g,4huattached to a strong string 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. The stone's spe n,2lzg p2,j2s/8dxdjyr49rc uh jhw;ed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when pultu 9kx32 i/ +d,vmiql:vw5ulpling out of the dive. W ,k5iv2uvlx:uqlwp 9 +mt /di3hat is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which thsss+8kj6ct 7.nn svk6e center of the loop is beneath him) of ranssjs ks6v6+. 7knct8dius 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 going?

  The maximum force a pilot can stand is about seven times his w1g1cd13 8/ jdyqb goaxeight. What is the mjcdogq/ adbx 118g31yinimum radius 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 rounds an 80-m radius horizontal w8+zx eo ://cf)wh(d5cwev ndcurve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Asdefn/x(c+o8 wv 5c zh)dwe w:/sume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a p f e(.gf*j+,m4jjbdrflat curve of radius 50 m with a speed of 20 m/s. The centriped.j+p,b4(e jrf f g*mjtal 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. What mus0xis kxf34v0z 4v+ls9grula0t be the minimum coefficient of friction between the tires and the road for thei4g0s0s+ru93kl4al z 0 xvfvx car to make the turn?

  A car is moving with a constant speed v aroun+m /7hvq+0haqnb) uspd a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum ra0q+amn +phq hb)v/s 7udius of the curve if the car is to stay on the road?

  What minimum banking angle is req(jf3k+ dr:tuf uired for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frick3frd:j(t +fution.)

  A horizontal curve on a bobsled run is bam h fd *ru*swf9;lt9z*nked 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 an har-m4adfq /v rga84.angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 mj8 0zu+n*s3hu9 s fnag is 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 /pw-.qnz k.f3eaxq. b a string is revolving uniformly in a horizontal circle.f/qnz .bq3we-.a xp k 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 accelerate0m7 wrci(dip (s 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 blarmpid0( i 7w(cnks)
(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 z: olmp zee(i2nda(+46tmucvt76k7j 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 onwct2a 91khxw2 a 70-kg person standing on the Earth, due to the Moon? The mass of th9w 2wc txhak12e 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 lmwkbif)x., )moved to hi)lf ,wx b.mk)alf of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at h /w /*tx+updhwhat distance from the Earth will the gravitatid /u/ph+*hx twonal 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 vaqm(rw l 2p8bp0 6hnd6m3 nq1is $7.4 \times 10^{22} \; kg$ 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-walk" at a distance abovew7hxgv 2a/j)3 kc i3rd the Earth equal to the radius of the Earth. What is her acceleration due tocj d72x3hav)wr3i g/k gravity?

  The radius of the Earth is R. whi (u 2d2p-fd At what distance above the Earth's surface will the acdf2 (p-wihu2dceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars d ulm2xx1o1dk-r7gw qe. h5+nat a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity +n 1xd2dg.lwr1xke7 mo5-u qhon the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleraa:+u 9zo9 9ngqtnqjy ,(p fyua8ri(v0tion of gravity isv+n8y9qapor9(u qa,j(i:fn zy g9 tu0 $32 \; m/s^2$. 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.483or6n(s v t5xoba/fq7t wql The Earth has radius r. If the object is raised to a height of 3r above the Earth's surfacsb(w7toxlq 63f t/4 av5ron8qe, what is its weight?

  By how many newtons does the weight of a 100-kg person cha fvhb/z8on,wyyx35 o 5nge when he goes from sea level to an altitude of 5000 m? (The mean radius of the Eaxvb/585wzyyoh nof3,rth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg i6h-li;oba.f cg s6nn *s at a point 3r above the Earth's surface. What is the b sh -n*g;ln6f.co6i asatellite's weight?

  A spherically symmetric planet has four times the *pis4.ff qi2s+v(ksqp kbu:1Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weipk .+*q 2ifqs4kb i1suv:f(psgh on the surface of this planet?

  During a lunar eclipse, the Mooe 2zjl cg5 2v:+)mzxqsn, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. Theqj2+cz2mv) esxzg : 5l 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 Mol./y ousx56t bon.
(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 (i.e., it just s4a3z;2 jih1c gjih j*rkims the surface of the Earth). What is the speed of the satellite? (The mean radius of the Earth isriihz*2ca;3 g1jj 4j h $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about (x o ni)tp; arr3db/pk 2xw--vthe Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean radius of the Earth -ab2- xnxt ;vdoprpr/ 3wki)(is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above th b3 /mo25be )eyzoy8vwe surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean/ome 3ob )y5 bwzy28ve radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter,j:u.ua;lkt x p.,yt,xhyx-(h 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 planet with a radim h lha4f 2c*syjmg63.huz9d6us 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 Amint: uc+3855v pgv5 s0khtvh has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete onc:8 g+ tt5iv kmu3h55vv0s nphe orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 6byq1b; bwqxr- s ,qfi1)9hi f$7.78 \times 10^{11} \; m$ 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 tbn 8d s+:ltlm ud3/gy+he average distance from Jupiter to the Sun? (The distance from the Earth t ynb8+/ u+:gdtsdmll3o the Sun is $1.5 \times 10^{11} \; m$.)