Is it possible for an object moving with a constant speed to accelerm8 g+rcb2gvc( ate? Explain+ v2 cgcgrm(8b.

  Consider a particle moving with constant spmi,6fl )as3yleed such that its acceleration of constant magnitude is always perpendicular to its6a mfyi,3 sll) velocity.

  An object moves in a circular path at a constan1 1 swu uez78.s7z+:oon5pdlw t2jvhkt speed. Compare the direction of the objen powo+zw8zlhjs vu .d5ut2:711 s 7ekct's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direcu9no/q/lf x 9.9t/l n5 mrkqxction of the accelerat9mq./ lto/9unf qc9nk/lx r5 xion is

  Consider a particle moving with constant speed such that its acceleradys)ec+0 .du qtion of constant magnitud 0ud. )qd+cesye is always perpendicular to its velocity.

  What type of acceleration does an object moving with cog+h :vz+d,tzru )t5tg wxn:;cnstant speed in a circularzzv 5t;: wdu ch+r,x+ ):ttggn path experience?

  What force is needed to make an object move in a j2 s-tgc , 0wmqh1u(n (wwir5xcircle?

  When an object experiences uniform circular motion, the direction of the nez(pffb*(/r vds/k n 1bt forcef r*s(b kpvbndzf/ 1/( is

  A roller coaster car is on a track th:: 1dujr:geg hat forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the 1:rhedu :g:jg 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 t mza yqxle1tx- i64 3bld3lwn9n ;4gk*hat forms a circular loop (radius = r) in the verti*4wlk q9l3xa by ;1zn- egm 3tlxdi64ncal 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 fol16n ihm9+ov-s+lsqi6a ep g-ulows a semi-circular arc until it is going straight up. Just mse-1 +a li 669vgho+inqusp-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 curve of radius gvc0.h37eoi f$r$ 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 constantn4w9,osua*)po x1vid9rxe y ; speed v. Then 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 thp ixx)149nr,y 9s;dewuv *ooae second time, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. h v63qv dtv 5kak0t9,fThen it goes around a5 3kf96a,qvvdtkvt h0 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?

  A car of mass m goes around a banked curvedx6/8 w7gyl99v 4b: aya-rzy twye *uw of radius r with speed v. If 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 fro *wya6gd8zwlyrbea7:-v 4 xy/w 9u9ytm the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, butybzasi q1k pgce)rfyla4;ar t67*+;0 one has 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 curs*0 rltz )f7br qp+6ag;ei; ycay14ka ve?

  The banking angle in a turn on the Olympic bobsled track is not3zt;uh 5bi dexyio7,6o*2iyi;fs i w /hctw 02 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. Wh 6o si22hthy; *i ibiiz;uoxf wetcy5/dw,70 3y do they do this?

  Is it possible for an object moving elb7ie 35o*u1pm9w vyl hl: e;around a circular path to have both centripetal and t 3e1levhu*po9el ;lbi5: m7wy angential acceleration?

  The gravitational force between two objects xs te/c;f i9-nis proportional to

  The gravitational force between two objects is inverse;bfeh rq.o5(z;iobs 2ly proportional to

  Two objects attract each other gravitationally.)j7(orutnb (utb 2g a 4nj3fr5ku 9fi. If the distance between their centers is cut in half, the gravitational forceu5)(u iu fbb rrt42(o 3ftnaj.n7gkj9

  Two objects, with masses rv2b. 4d sdwq9$m_{1}$ 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 masvyx7n fm0)z s9ses $m_{1}$ 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 grav sf(/ 2rg(k1 u5yqw.yqbrg.sn itation.

  Compared to its mass on the Earth, tz21;,pzkn tsthe mass of an object on the Moon is

  The acceleration of gravity on the q* m eqzsz-*sj8l1; :efl 5,7 snwvnruMoon is one-sixth what it is on Earth. An obj e5,l1*sjs 78snuvrm*znqwz :efq-;lect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, tf kf2q7d ,ur)en:hjx *he rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull o5zifi/m 5 stw /lzym71f Ea zmys1f55t wi7z i/ml/rth's gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What is it.eozojo (.o h o7)ox3hso(7.zo 3j.o ohoh)e ox centripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a rd;a1bng8a.cpzxmo ..h -m ftx )s(6c yadius of twice that of the Emcan pxhd ).6fx m-o.y(ctbz;as. g18arth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity ont/pa7m8nrfs 0v0 wdt) the Moon is one-sixth what it is on Earth. The radius of the Mo/arvm0w)sdt8pt7 fn0on 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 has5 *hj-smn txi0 twice the radius of planet A. 5sxt*0-ihjn mIf planet A has mass m, what is the mass of planet B?

  Two planets have the same surf/ xc7qy ,lepv1ace gravity, but planet B has twice the mass of planet A. If planet A has radius r, whatcvpe/l 1yx ,7q is the radius of planet B?

  Consider a small satellitm.nwvuk2fg87o8w -twe9 ja . ne moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives 8gtfkwaonw-.7j8u v.nwme 29this satellite's orbital velocity?

  Satellite A has twic9y5iop 0( ,olpynd ui9e the mass of satellite B, and rotates in the same orbit. Compare the two satellite5iyp yd(p0 u9on,o il9's speeds.

  A person is standing on a scale in an elevator accelw+ .rv *uvwsh.,izeb1erating downward. Compare the reading on the w*vi1,z eush.r b.v+wscale to the person's true weight.

  Who was the first person to realize that the pla*uqp3 *hz dd8f tz98dynets move in elliptical paths around the Su h 38pdduq9zd fy8*z*tn?

  The speed of Halley's Comet, while traveling in its elliptical 5l(ns7u 9roexorbit around the Snl(5xs ur7 9oeun,

  Let the average orbital radius/vn-atf8w 59 + jbplov of a planet be R. Let the orbital period be T. Whao+n5vvj w p-fl9 ab/t8t quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galxq(gyzw+ s f4p2h* g.yaxy Andromeda, with the same orbital diameter as the Earth around our wgx.hp sq( 2y4f*gz+y 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 tobl6b65h wgdo *gro97 f the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's avw9656frb dgol *7 bhgoerage distance from the Sun?

State Kepler's laws.k8 l0*wdf+y3*lu wzz e

  List the four fundamental forces in nat t;( qprzhyj9zytm 0(9ure.

  An object moves with l kbbnoeqc*3-)4 bi/ ya constant speed of 30 m/s on a circular track of radius 150 m. Whatlq n-eib)o3 cb/4*ybk is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/ qhjy jeeum:4ds1)uh - 9h8t;ph. What is the maximum speed around a curve witdh: upq m9-tehu);e8j4h ys1j h twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal accellcbg,50c +f.ex5 hies7, krkleration of a point on the perimeter of a bicycle wheel of diamete7 c hc,ex 5e+gfrb kk.ils50l,r 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 revd. er.b uxs9y474 rofs/s is located 0.200 m from the axis. What is the7ru 4syrfb4xoe. 9 d.s centripetal acceleration?

  How many revolutions per minute must a circular, roe3h .9- g+rv(ptmfke otating space station of radius 1000 m rotate to produce an artifice eofm( p9k.g3-+tv hrial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes ar/ek j zef4deg0dh1vf;6 j4kx:ound a 13.7 m radius turn at 96.5 km/h. What is the centripetal fo0j fxgjd1kdzv e4k h:6e4f;e /rce on the motorcycle?

  A 0.50-kg mass is attache0**fwhdzn2.) zzr f/xwjnpn5 eqd6 .j d to the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that theh f ) w2*rdezwj jq56nz.z/n dn0*pxf. 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 st az- -0mmu)dwirong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in0 )-izuwmad-m 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 whirled in a vertical ci 6yfo.n.xld y)u o1z4brcle of radius r. At the exact bottom of the path the tension in.4y)nyol zxo6f d1u .b 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 ex*4c xd 6zww) 1nfbx;mtperiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the platx6 )md1w xnb;wfz*4 cne is flying?

  A pilot makes an outside vertical loop (in which the center of the liugidc z7h, 46oop is beneath him) of radius 3200 m. At thu6i7gzi,4 d hce 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 weight.dz k12mn-2db g What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive,-2dbmzgnd2 1 k can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with *tgqo kk/lf8v 5k.sc0 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 ak.kk 0q5 gfots 8/*clvnd each road surface.)

  A car is negotiating a flat8 s+e1/uvo9zmy0v lfkbexun g-d/ a(+ curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by friction ( 1 vn/ +beyfvo e +lgx8-09dszkmuau/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 must (5vv+c4ysa syp g:,bwbe tas svy,pv:c54(+ywg bhe minimum coefficient of 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 levep t9f wgkg9*im-w(/ gsrh 7ru/l 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 topw gr*hfig/k7t9g u/r-(9wms stay on the road?

  What minimum banking angle is required for an Olympic bobsled to7 yp0z1nke0 mo negotiate a 100-m radius turn atnp7mk01 z oey0 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banke6khmhv582mc f x5lm.)jibo yz.79bgxd 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,l l0puz-t(jgg9bhk: f+ace4-v929pm-ab zd i banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is ba88 i4hw wsh j86+a2qzmht2ydx nked 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 s .fswfo sgf-cm ;-5ens41m3juniformly in a horizontal circle of radius 0.scs;efwm s f.gj13- mn-5f4o s500
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 rate tos6a3 y z/p xuw7h3uqd0: p wv+i9kz0)gn8lqvu a speed of 45 m/s in 1s )709z /u lakq63+u zvgvyu q0ihdwpn:w3p x85 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 o5wnn m0i. qs4vf 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 y ygx5tfl1yq4u z)x0 9on the Earth, due to thy0yzxx 54y uf9q tg1l)e 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 massecd:+f onje m,0s are moved to half of their initial distmc o,j+0 :edfnance, what is the gravitational attractive force?

  For a spacecraft going froco7lv738l v 2;cpzk gfm the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and7flv op 837lkgczv ;2c 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 io.o-8j1lc,notvrzhyiz 0h 0 4 s $7.4 \times 10^{22} \; kg$ 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 disa. jl ,i3sndm 1xvo1-stance above the Earth equal to the radius of the Earth. What is her acceleration.anl3d osi-v msj,x1 1 due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface wg) 48* bx ixphvndt/7pn-rqp+om6x x 9ill the acceleration rpbdx7-nh+ )q48npxm6x9* o/pvxitgof gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal psdu)of f*v4*to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the accelesdv *p)4ff ou*ration of gravity on the surface of Mars, is

  At a distance of 1400-ms ,,5lgt(rb9h4s x zft v;ij0 km from some planet's center, the acceleration of gravity; x,-t5 z h(vbg4ssfit9j,lmr 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 N on the surfnct r)87fgzd /eo./uface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what cz dnfg)o/f/7.ur e8tis its weight?

  By how many newtons does the weight of a 100-kg person change when he goes fs- ib*w.ny ov*q1ojcl z3, 0wzrom sea level to an altitude of 5000 m? (The mean radius of the Earth ibz.*slwo o-,0q3vny1c*zj i ws $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100zvg3 3n36sukr kg is at a point 3r above the Earth's surface.s v3k6n3r3g zu What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its rad3bvq132ok eg3p 7dcg4 gta;aqius. If a jar of peanut but qdv 4q33g2acg1te;akb o p73gter 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 line, withhz) hat 4at+a- the Earth between the Moon and the Sun. The Moon has a masthza4)t -aa+hs 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 Moonep1 :b g z.efhkv-lf3(.
(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)c+zw*orh / bbyol--v x 5gjp3 about the Earth (i.e., it just skims the surface of the Earth). What is the s)b j vhobozpr 5x- cg*y-3/l+wpeed of the satellite? (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 sk p2hv09 fk3yjq,;zo(zm / mwjx8b v/flims the surface of the Earth vpf3(myjm ox2vl jfh80q/9w ;z,/kbz ). 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.)t9 t mkmt86 o(spdx.6 sipt.v It is observed to have a period of 89 min. What is the masspt xmt9.m(tsd )6t8. io6pksv of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbitaw1 qs3 3hxq aen-k37(5kc /jyenrp1til 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 l q4:b(is-xn u qwzg(1ow40cqJupiter orbits the planet 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 orbits.datfgh 6./to--2 qrwz Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?. /d-ftqr26hotgaz- w

  The planet Jupiter i 65jz: gc1, zvvadonm:- uvf(zs $7.78 \times 10^{11} \; m$ 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 1r.jus g u7s .+0rwdxb(2 years to orbit the Sun once. What is the average distud+xg7sj.r.w( 0 rsu bance from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)