Is it possible for an object moving with a constant speed to accelerate? Expla/g 1qrf (t n9e9wvvrbru8.iz/i/g .9(e8vru bwn9rt/ fqvzri1n.

  Consider a particle moving with constant speed such that its accelehjqck*hhlk (f t -2rc)b*/ t-lration of constahll hjkc *tt/ f*-r(qhcb)2k-nt magnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Com p mw- z e:pl pk.-0clt/teyh4hw5p7a7pare the direction of the object's velocity and accelerationphl5m 0ap74:- z h /cw.t7elpewyt-pk vectors.

  When an object experiences uniform circular motion, the directc a5d .wz5lg5 *q5nevsion of the acceleratioqd*55 w5avzec.s nl5g n is

  Consider a particle moving with constant speed sucwtoj: 9yu3k 9eh that its acceleration of constant magnitude is alwa e ouj9wt3k:9yys perpendicular to its velocity.

  What type of acceleration does an object. tqnkmve i25 w1fk)h7 fsq1 hw57l3vk moving with constant speed in a circular pkwvw k) q7n5 h1vf 25ilm7q sth3fk1.eath experience?

  What force is needed to make an object move in a circ og;rsn8akjq.1wr ke60e (:rale?

  When an object experiencesrlfmd+je 9f9r zlq(+ 2 uniform circular motion, the direction of the net force isd+(9lmqefr 9+ zjr2lf

  A roller coaster car is on a track that formserw9/r q r+viyk.qtda2hw3 bm8-q 6.t 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 minimum value for its centrqk8ym.-e vqrb +2a t r9iqh .ww/3drt6ipetal acceleration at this point?

  A roller coaster car ( tz) ex p jn2kuseilk2m01h27og;-i +umass = M) is on a track that forms a circular loop (radius = r) in the vertical plane. If the car is to just2pi 2entk)1 u jxsg2zm0i7u-e+;kh lo maintain 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 vrzokd86 i3ntcmy 5u(snc*4ne(dhr(: ertical dive then follows a semi-circular arc until it is goiy d tz i3mhnn8uorn(e:c d* s(c6(5k4rng straight up. Just as the 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 cg/bp91n vbe-.v1nwmrurve 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 constant speed v. Thenen1qjjy90q q + 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 ti y91e jq+jnq0qme, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it r;n osg wnfct:q1hm-ip *.-fp9z0v5 w9:vtrugoes around a curve of radius 2r at speed 2v. What is the centripetal forww :q0riutfvsmgt * :c;v nn.9 5z-19pp of-hrce 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.gg7ira 2bqd 90 If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component i7b2ar g0q9gdof the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angl, 0l;spz )lpx0*jr3 3ugygk wke, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius ppw*usygg j0; xkl)l ,kr33 z0curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a 94qgaa:vx. e mturn 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 la 4e xq9.:mgvaower coming out of the turn. Why do they do this?

  Is it possible for an object moving around a circjnhm*,9xu qppq9w3 u5ular path to have both centripetal and tanh*pu3 wj9qnq59mx, pu gential acceleration?

  The gravitational force between two objects is proporl*mg0d 0 wwf9htional to

  The gravitational force between two objects is inversely propga9 ggc1hhj3/ortional to

  Two objects attract each other gravitationally. If the distance betw/74s itolwq- zeen their centers is cut in swo/i -z7q4 tlhalf, the gravitational force

  Two objects, with mass1ak.mjn9,rl ku) sm4ces $m_{1}$ 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 massele pa9788odry7. pff-j ie sld3d ba7:s $m_{1}$ 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 gravitatioqxvz6k8r 72al/f4- bwqzdkq+5 l 6yk mm;uk1m n.

  Compared to its mass on the Earth, the mass o/ck8 9kv+- auakm9mybf an object on the Moon is

  The acceleration of gravity ongbblt k*c2z( 2 the Moon is one-sixth what it is on Earth. An objebc*bk zlg22( tct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away sj0d;4(xuk4n. qw2x8gq4sn4 u a4dypvr. zijfrom the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moo( m)*mu :+4s)73ovgyluiflg3r 1wv m atxqj2xn. At what point is it beyond the pull of Earth's g g* mlxt+ug3 ysqa)3:xomv(4mr)ulfwv 1j2i7ravity?

  Suppose a satellite wq haw0fmo1f-7*iw *ghere orbiting the Earth just above the surface. What is its centripetal acceleratiwif h*07*f- wgqmo1haon?

  A hypothetical planet has a mass of half that of the Earth and a radius oub0 )butlf-h+t loz l6vg0cuap. *dzy8 9 .fy/f twice that of the Earth. What is the acceleratt/f80a +l6zu..0)gv -*yylu 9dczuh otlp bbfion due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravitydoe;g0vu *ov3 ase+ ai ik,/y6 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 to th/iue +sod,k v*06v3o;gye iaae Earth's?

  Two planets have the same surface gravity, but planet B has twic8;zkliw(h y2f/ re708 gssxaoe the radius of planet A. If 0 eik lw(27s;szy h8/8xof garplanet A has mass m, what is the mass of planet B?

  Two planets have the same surface.qku ptz*mm ae 5v,(t6 gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of plu5tm.(ma6zk*v, etpq anet B?

  Consider a small satellqc g:s11 sno((h0whji)ps( m yite moving in a circular orbit (radius r) about a spherical planet (mass M). Whichsc s01o(pq nw)hj(g(:syhi 1m expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotay8o/ti;-z0+wyiq e zn tes in the same orbit. Compt+oi-zyqe 08i/; zyw nare the two satellite's speeds.

  A person is standing on a scale in an e p39r* jc e0yw:xyut3*tnxgo/ levator accelerating downward. Compare the reading on wug cyn*/exo tx3j rt 9yp*0:3the scale to the person's true weight.

  Who was the first persid(p(nj5 qv/s/rp/ jlon to realize that the planets move in elliptical paths around the Sun?p(p /jd/r (nqlj v/5is

  The speed of Halley's Comet, while travelq5 a f)ckoz5z.ing in its elliptical orbit around the Sko 5zaf).c q5zun,

  Let the average orbital radius of a planet be R. Lvv9pwyrexi: o/(ge/ 1et the orbital period be T. What quantity is const vir /gyp/oe9:(v1xweant for all planets orbiting the Sun?

  A planet is discovered to : 8i6rzjl/ baf nlj)k;orbit 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 our Sun, what will the period of revolution of that new planet be, compared8l6)kjb/na f;lj ri: z to the Earth's orbital period?

  The average distance from the Earth to the Sun is definedm9/z( 6e eu.qz *inaeekz):a e as one "astronomical unit" (AU). An asteroi/qu 6.mz k 9zeieene)z(a:e*a d orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.6kj9bydyhg vfi6c0:0

  List the four fundamental foojie/ie9g mn7k6w/d 0rces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radius 4if*fobpv9nr1nwb , 8150 m. Wh noi4bbfp,1*v wnf8r9at is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is t,yogh9) rgfw2l1nii)he maximum speed around a curve with twice the radiushif n2wyg g)r19 l,o)i? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point o:daumy7s: -b bn the perimeter of a bicycle wheel of diameteruymb-a: sd7:b 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 axigu4w 2jvw y(-y/.dbib/d+ nva s. What is the centripetal accelea+d-n b(.uv 4y/iw/ 2vby jwgdration?

  How many revolutions per minute must a cir+p 2j*zubiogy wd/l 8-(ogi u6m)n8e-r. zkxbcular, rotating space station of radius 1000 m roz glb*bo(8+i8y/.-pd o j)umi g-xw2 nrue6zktate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 25gam5 oi ofb s75rf (g6t7)o u:aej)i.l0 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcyclof )(5el577)i6b:a fjugo. so im trgae?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The 9r9r78sv5/jckl zrk+w(sx k usystem is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed of the mass if the strir7rks lv/cks+kx8rz 59( wju9 ng is not to break?

  A stone, of mass m, is attached to a strong string .)jein:xjh(2 vv v x208smazkand whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The s sxjhe8.:m0 (ka ni 2jvx)vz2vtone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whyri*; t7 ja3xwirled in a vertical circle of radius r. At the exaciawr*;y j73 xtt 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 acce 4vql5kpl 74r7siaq dm0 gsh9(leration of 4g when pulling out of the dive. What is the radius of curvature of the loop in wqq 4 agi(m4vlpdl5077 s9skhrhich the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop is b zbf3. +bl .v:jmpr 8,i20wxhrejivz: eneath him) of radius 3200 m. At the top of his loop fp ,:xz 2+.ze3jvrjb0 8h:.blvwrii mhe 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 stbx j(2 5djqf2oand is about seven times his weight. What is the miniq jfb 2jd2(xo5mum 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 curve with the tires on u 2j ob4xjx0ney,k sym*252nn the verge of slipping. How fast can this car round a second 22n mn2jyo5buj0 kysx*4e,xn curve of radius 320 m? (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 p:h :y*r3duetwith a speed of 20 m/s. The centripetal:h3 *yrputd e: 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 *skk7s nx6( to7ia 5uvm at a speed of 14 m/s. What must be the mik n(ixoutv7*76 5s kasnimum coefficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed ci8mbi2njl o:x9c0g)1qi ab:v around a level curve. The coefficient of friction between the tires andg i:0l bc9bx onmqj)1 2iaci8: 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 forvkue;bxb758)j 8qfhy) nv tv) an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fricttyeqv7hu x)j;)8f ) 5 vknv8bbion.)

  A horizontal curve on h;gpd. r-gp e9a bobsled 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, b;54/h r1dave,ed xnjqanked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i+*z8l2gn va7vtuj nb 4s 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 uniformly i2 ,cz(w)ix wvqjok n/0dms8zo rzk at5;y 5.+in a horizontal circle of ra s5, ko2ai mkjv zoztc(w)zqr0n .w/dxyi;58 +dius 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 ratenwuju3i71 2 ao qqs7z0 to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fil7q1ua uq znio 70j3ws2l 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 sg agsa *vh43 l91lb60lows pf2mn45eof 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 fx . y)nr5+pm2e(ohs vporce on a 70-kg person standing on the Earth, due to the ps+y2 5oexnpmrh)( v. 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. Ifhzg;6885*h c xs qutu:amq9fy ,1lri-e wv.mp the masses are moved to half of their initial distance, what is the gravhcmyz ,;q.t x*5mlu pe:qviurfs-wa 68 8hg91itational attractive force?

  For a spacecraft going v)jkjpi3+t(;n ok ul* from the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth cakt j3;kil)vo+jnu* ( pncel?
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 isa4rznjg6fmq w7)w kahw;-/o 9 $7.4 \times 10^{22} \; kg$ 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 distan27tgzl7zs* e09y 7wfn mi xr-gf3 (ruoce above the Earth equal to the radius of the Earth. What is her acceleration due t 7xw 7 2ng(* e9zlizsrmgf7ru3t-y 0foo gravity?

  The radius of the Earth is R. At what distance aboveyl werjpa,x-x8t4w91 the Earth's surface will the acceleration 8 xjawx ,yr-p9e1 lw4tof gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at od4. 6k5 hvd5sv7jnjoa distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, oj564d djv.h 7nksv5oas compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 140v/z qf;6omay w 02xsg900 km from some planet's center, the acceleration of gravity is z so qfway;xvm/2 9g06$32 \; m/s^2$. 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 E fgsw2gq5g(f; arth has radius r. If the object is raised to a( gg2wfg;fq s5 height of 3r above the Earth's surface, what is its weight?

  By how many newtons doq m,: (tlwt89ua :kpqqes the weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius 9q: ,utmlpkq (:t8 qwaof 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 t5tgklcl( g ;a1 +i/qgshe Earth's surface. What is the satellitlg +c ta;kgql51isg(/ e's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its rad2 tg9/4r wkniaius/9 kwain4gr2t . 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, and Sun all lie on the same 4m hmk dad1ad+u3 vq63line, with the Earth u 43adm+mdqda6 3k 1hvbetween 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 transportedbo w)8b5x*mpqw5f+ g4vz*j;zbm;s*e h .obwj 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 orbi- k*eh;n;hu 8rr f/cfi2n 5qcst about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of ti;*uf;-csnren2/frk5qhc h 8he Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (9bcsm/u;*+hdwgc p n h:b7 xne a6q:0ei.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 hmed0bgaqecbxn/ 6h+*unw :p97sc :; Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in cirfm* .h)n j9 jl- rfzzk*gi3o)ycular orbit 230 km above the surface of the Earth. It is observed to have a periodm lgfo)j.z r*khz9fyi3)nj -* 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 Jupiter, has an orbital diameter of qg4e90qq;hvy $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orbits the planet wq /)fkwbw3 1sdith 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 nearly circular et3/jtz8+ cayma .b.(r2-t)b vqqm ztorbits. Moon A has orbital radius r, and moon B has orbital radius 4r. b/ya83at- te(r+zjm.mv. tb tc2zq) q Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is s/uy vwn ;s,mlrl;, 5sngf) e2$7.78 \times 10^{11} \; m$ 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 yl( fjb :sv 8tic7+:qexears to orbit the Sun once. What is the average distance from Jupiter to the Sc f:7s qbvel8(tx:ji+ un? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)