Is it possible for an object md istfhp8s++kq -jy+x)i/ wg8oving with a constant speed to accelerate? Explainpkiq hxitj+ +fg- ys8+ 8)swd/.

  Consider a particle moving with constant speed such that its accel s) p8)ixzq2za wk8hi,eration of constant magnitude8zqh i kia )wxs8z),2p is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Com ige0t7pp9 nzeg 33h-upare the direction of the object's velocity and accelerah- gtp03 3euzgpeni9 7tion vectors.

  When an object experiences 8n t-c:2rk3ei myj a7e5plo5zuniform circular motion, the direction of the acceleryk3:tzo 8rl7e5je-5pamc n2iation is

  Consider a particle moving with constant speed such that its accs 4 jj3vc/u77tjli2 gveleration of constant magnitude is always perpendicular tcgi2 u7vj3vj7tslj / 4o its velocity.

  What type of acceleration does an object movi i.6.-,clorylw0v6 ccex eh5ing with constant speed in a circular path experihryl w.ev 6clx 0i,ie o5c.-6cence?

  What force is needed to make an object /i9lclor ;yq4w rd1/dmove in a circle?

  When an object experiences uny4+;k ed pt)8bx0o scciform circular motion, the direction of the net forced4+ bycp ) s0x8otk;ec is

  A roller coaster car is on a track that forms aln 6my;jsi vup (1+. cnkg9/rh circular loop in the vertical plane. If the car is tr/p. 9sj nui6hm;+vly(gnc1k o just maintain contact with track 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 y wvtn0bj27v:track that forms a circular loop (radius = r) in the vert7vbjn20:wv ty ical plane. If the car is to just 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 vertical dive then follows a seszq1b23 6mipus ul ..pmi-circular arc until it is going straight up. Just as the plane is at its loulqp 36i pu1.m 2.szsbwest 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 curve of radius .mq9 )dto j9(xzdc9hf7+1 /mkpk ohod$r$ 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 kspwz+t:7e5b p cbwu)7bk13h 1rsar+at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the +zcr31eb rhwaspk+p:71b 5wst7)buk 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, b0myg x*dztph+8rb1 goes around a curve of radius 2r at ,zrb8m0b*t1ghp d+yxspeed 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. If the gfx83 n va*8eg1sexu):u( vev road is frictionless due to ice, the car can still negotiate the curve if the horizo *v1 nvgee (f8xaev)x 8usgu:3ntal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled ruupd,a)p pk, ol:*,q zen are banked at the same angle, but one has twice the radius of the other. T, opd:zk)q,p ,e*ap luhe 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 / plmcts5f4x1m c3f5wthe Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "clim1lf t4mx/f5p5mscw c3b the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object moving around a cqf0hmz9poai c0zaw + ,-8w od;ircular path to have both centripetal and tangew +dwcoop;m-z0ah 9zq8 i ,0fantial acceleration?

  The gravitational force between two objects is propo*q4goyx)49 ydc93qq .p/ o(iy biejd mrtional to

  The gravitational force between two objects is inversely proportiong,x5xts5l*d sn jw495(gc mtlal to

  Two objects attract each other gravitationally. If the dis-e fucxgxkngf +. vcy5tkk9e,;df5/(tance between their centers is cue g5ky(+/enkv5ccf 9-tg,ffdkx;.x ut in half, the gravitational force

  Two objects, with masses f z:g)g/wa1 gz$m_{1}$ 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 masses.g(xon5b b .dt $m_{1}$ 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 gravijj3ti /)vy*k ttation.

  Compared to its mass on the Earth, t- 5jhjb 6ie my adslr-;6i5;vthe mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it i6zfxa8j8l)kt , x1e bns on Earth. An ob6a,nebf xj81)xk 8lztject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sh /s/ha5j -)ffy-y rlpurface, the rocket's weight

  A spaceship is traveling to.4uj6dc xfq+j9fi)d x0j-sfg the Moon. At what point is it beyond the pull of Earth's gravfdqsjf ) jx 6fcd u+i-gj409.xity?

  Suppose a satellite were orbiting the Earth just above the surfa8( mzd jfi16cgce. What is its centripetal acceleratjdif6( g1c8zmion?

  A hypothetical planet has a maskf /cg/t gs d8cs-9()eb1uzx n do9mi g4-:ynvs of half that of the Earth and a radius of twice that of the Earth. What is the acc/4x)i ngzsc1m 8fuy9(dkg-v/gsce-bn otd9: eleration 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 what it is on Earth. Theme w4v(vjv 07b radius of the Movw bvm7e04 v(jon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravitc o s*ra:ka 3:tfx3z,ty, but planet B has twice the radius of pla:aotsck 3*rta 3 fzx,:net A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gm:lk( 3pf,or2 m spz+rravity, but planet B has twice the mass of planet A. If planp s32mfmr,rk(+:pzo l et A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circp0*: po)zyfcgc m3rw *26q0ewe/ afh tular orbit (radius r) about a spherical planet (mass Ma qf3r0ye gc0o /w*:tcpfpw 2z)*6ehm). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbityhvj p89jbuu(rt5 ho3),kt g5 *jsvm 8jg 6e5c. Compj5jbp*g u 6e8 ujto8h3tvgv,k h59(smy) r5jcare the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Comparyn wy:nr -ju- xs/g.m;e th-gjn unmsyw ./x:y;-re reading on the scale to the person's true weight.

  Who was the first person to realize u j; mfus6chkjinq4.v t yq9o/9m; .p,that the planets move in elliptical paths around the Suuvhop/4j ;c.m9 ; tjuy,qs.ik69 nfqmn?

  The speed of Halley's Cqv/,zsh a4ot1 j jom: vur0+s0omet, while traveling in its elliptical orbit around the Su+ ja z,rsh4svq1 ou0mjtv:o/ 0n,

  Let the average orbital59p mx:9 pjn:v,v vs2bfj4 oyw radius of a planet be R. Let the orbital period be T. What quantity is convpvjoywv94b9 :f,js:5 m 2pnxstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, witt;3j0ger zek *6ek(sth the same orbital diameter as the Earth around our Sun. Ieett k63je*k s;(z g0rf 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 from3m 5z-;,rkljfa y(hxd the Earth to the Sun is defined as one "astronomical unit" (AU). An a-x 3h,fldarm5;yjz ( ksteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws. *u)0knnmmxwmu u ;8v:.aly9e

  List the four fundamental fodgej.my n45,n-l* yup08fny r rces in nature.

  An object moves with a constant speed of 30 m/s on a cir g8t6rr:o(e epcular track of radius 150 m. What is the accelg68(e:p ot rereration of the object?

  The maximum speed around 56fm qtk*g 5fxa level curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assuxq5fgm5 *kt6 fme all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimete b sv /4d(y0.+nnxfggrr of a bicycle wheel of diameter 70 cm wy d ns0gf.+brx/nv(4ghen the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.jkypv 7+h); :t )sqoye00 rev/s is located 0.200 m from the axis. What is the cen+ );ehy7) spo :tqkvjytripetal acceleration?

  How many revolutions perw,mteo 16ko5v minute must a circular, rotating space station of radius 1000 m rotate to produce an arv1tewm 6o,5ko tificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 2;al 7 u.egmh0q 2dql9v50 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centri2l m0q;uhaglqv9e 7d.petal force on the motorcycle?

  A 0.50-kg mass is attached to6.rxlo)g h 4fv the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the)rlx o6vhg.f 4 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 attan p.*zvqx;uqed hr h58e3z ;/fched to a strong string and 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 stv;rh;z*zfqe.xqn3 hp8/ u d 5eone's speed at this point is given by

  A stone, of mass m, is attached to a strong string baa-l/ xx bu8(-e+ih+ayb(e nand whirled in a vertical circle of radius rbnax8-bal he(iuy/ex+b - +(a. At the exact 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 experis:s/9kpf5 tenzjbs 9g*sl6 :f ences an acceleration of 4g when pulling out of the dive. We 5f9sl :sfns6 zj9b/:*tskpghat is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the l2,pt a ilj t7vl.,j xh,ozt9p9oop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on hitiotv, 2, 9jhl.pt, p9jl7zaxs seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven tizj0w 4f zb f/74np,ujxmes his weight. What is the minimum radius of curvature that ajuf70fn b w,p4 z/zj4x 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 horizont 67ci;twynz0 ual 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 road surfacecw 7t;n i6uyz0.)

  A car is negotiating a flat curve bk694o()v4o pvl hlnsof radius 50 m with a speed of 20 m/s. The centripebp lo 4l9(k4vos)6vnhtal 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 ol6olqh: m+3 vgg p)szn :of:2yf 14 m/s. What must be the minimum coefficient of friction between the tires and tvm fq::+)p 3o26yzgl: lnhs oghe road for the car to make the turn?

  A car is moving with a consth4 u aq,rres 5u8f,.cmf/ gks2vt /a7oant speed v around a level curve. The coefficient of friction between the tiru8quh,/e c sr af /,vo72artsmgk. 5f4es 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 Olympi gsa;ui 7iarwf) df;0d6v2u5y c bobsled to negotiate a 100-m radius turnw 7u igd;d6;i)aay f2u5vfr0s at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is(dc n divbw zx((2ky35v.i v;p 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, banked at an pf vd5s5+df1(9hn .lefcrd8uangle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked740w*l . a2gosq sivxw keg5y7 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 in asrs7x+mlhcaeu 5f .o viif,,ji 112 (n horizontal circle of radius e(1+5 1mv.s,sj i hrani2c ,xlfi7of u0.500
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 carf ftkg+,q6fn 1 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 n,gkt+6 f1qfffill 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 f /d/8ip8bpsi 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 p;+4z ctmez r-verson standing on the Earth, due to the Moon? The mass of the 4vr zemt-c; +zMoon 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 ox/)8; (dvuxy hqvn -htwo masses is F. If the masses are moved to half of their initial dix/d8u-n v;vh h)(qxoystance, what is the gravitational attractive force?

  For a spacecraft going from the Earth towas: p.0pr :)8lxvyo +l qdh:mf8 khyzjj4eyd27rd the Sun, at what distance from the Earth will the gravitational forces due to the Suny vmhd hd80js+l)o xj2 zqy7k:ye8r:4:fpl p. 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 j1)*elss s.6bed:eu 2bx+/a 4g ganwlis $7.4 \times 10^{22} \; kg$ 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 outw*ghihi() 8il for a "space-walk" at a distance above the Earth equal to the rwh*(i ilh8gi )adius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is daa-qh8by4hgyo,8 c *ou m9 9gR. At what distance above the Earth's surface will the acceleration of gravity be 9hayb *- q4mooyh ,aug dg9c88$4.9 \; m/s^2$?

  A satellite encircles Mars at a y+ w hau7nt,dq n9/,ymdistance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration +a/qyty97 d,nu,nhwm of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the accelera x q1e*k onr9..t8dglwtion of gravity isgt1 rk.o.wn qd*x9l8e $32 \; m/s^2$. 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 Earthng+ tn 2ifh:fqg,u--j. The Earth has radius r. If the otqgguhf2,ni+n: j -- fbject 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-k.3c.n )(zk ;aro)ad/ ocobupxg person change when he goes from sea level to an ./ ucn ocpdobr3k;z))o(xa.a altitude of 5000 m? (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 poi5jsuggt-2+d--on w voa4 6oo lnt 3r above the Earth's uogd 6 - j-s4w2olt+on-g5 vaosurface. What is the satellite's weight?

  A spherically symmetric planet h+ f otf f;8aux*:4rom5+fhmetas four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of ff4r5f8tu;*f+axmohm o:+e tthe Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Mz-6zg 1s;sqp q0xbpkixu k97) oon, Earth, and Sun all lie on the same line, with tguskxzpi- x6ks9)z1;b0 qqp 7he Earth between 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 ( );lgrds/a wcis 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 lohirpa 9x)20s iw circular orbit about the Earth (i.e., it just skims the surface of the Earth). What is thi0axp)s2i 9rh e speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a 3,lffb: ) - ijap)5lxi0mqx1umv+jq olow circular orbit about the 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 -m,fxqp1v)5lu 0ox f:)j+aj 3imqlib radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km abfvx8fhz )i5yoef c-/)08 xeol ove the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius 5o80c)f -zxlo vi)e/fyhx fe8 of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an wt((nkuz l9 ,oyhuct *5lhq -512ywvsorbital 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 planetrk z( zv6a-d)3x,)lnws l2wgy 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 in nearly circular orbivv;cssop 1 iug ycb;t.u,:- e+rsv:8wts. Moon A has orbital radius r, and moon se-s:ro8b wvy1,.utv +;pv ; sgc:ciuB 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 i ot zv9bxb5+u(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(5( nxr;rte6,sz wyn u once. What is the average distance fromrt(; (n wnz5yr,uexs 6 Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)