Is it possible for an object moving with a constant speed to accelizjfyj d0ym: gw6v,k; z683ea6i*yzlerate? Explainiyykiw6gdm lfz8,3*zz 0je: a6vy6 ;j.

  Consider a particle moving with constant speed such that icf3i ; s75qpsyj6/cris;fe:its acceleration of constant magnitude is always perpendic ;:js ey5i3/fsciqsp6fr ;7icular to its velocity.

  An object moves in a circul1:mxj .z3agq gjcmw29ar path at a constant speed. Compare the direction of the object's velocity and acceleration vec1 c9j2xm3w.:qgma jzg tors.

  When an object experiences uniform circular motion, the direction of xul/bp .x33 b nrmg-p1mxibb:fj7 2 i3the acceleratiob-xp2bf ixiur :p.mmnb/ 37b lg3xj13n is

  Consider a particle moving with constant speed such that its abpt ,d+gtjtifp-qw 9 ti6.l-6 cceleration of constant magnitude is always perpeg-. pbdp+tlt6i 6w9tqtji-f , ndicular to its velocity.

  What type of acceleration does an object moving with constant speed in al..fooxbuu/ c w7 +*1fyow/ 71ucoc cf circular path experience?o/w*obcw7uyc1uu fc7/.x1 of+co.l f

  What force is needed to make an objec-s vt,68y0 hx8kwc uwkt move in a circle?

  When an object experiences uniform circular motion, the direction of the net1uyrupb u-g.* force .1y pu -rugub*is

  A roller coaster car is on a track that forms a circular loop in the vertical 23sd n qq cr17dnkw*g;plane. If the car is to just maintain contact with track at the to 2r ck*nq;ngdq3sd1w7p 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 thnw0)vbk)c 3 xtat forms a circular loop (radius = r) in the vertical c3bvwn xkt0))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 follo8-3n4vzyss p4t 6u grzgt-z 4jtfo6 ) c:rpl/kws a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force ) 4z n4z:rutj6ogy4spz-r tg /l6-kf cp3 vts8on 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 o)yv+) zb lsnfmz0;m(b8*ap u pqxv*h-f 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 spee rjinv1mmo9 dh10a 3zvx ,f8g3d v. Then it goes around the same curve at half of39h3njgmv1 zd1orfaxm8i ,0 v the original speed. What is the centripetal force on the 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 spe w-3 htgebspl gx,,68eed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes ar36 wgp8-s,ee thxbg ,lound the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with sp:.2 .+c 6-hs d) blez fgtwo+xrlnimr6eed v. If the road is:-m ho) tz+d.e2+crx66 blgsrlf wi.n 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 to

  Two horizontal curves on a bobsled run are banked at i)c5v*iv k rr(jj ( z *8xggulvc1kl n2ecq.,)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 radic51ec) (*zvl,kxj gqg *iujr(k) n8l ic.vvr2us curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled jdvw5h(fm 6v 0xo (b3vtrack is not constant, but increases upward from thxvjv( 3d(hw5vfb0 6moe horizontal. Coming around 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 moving a cm- 0hyftkkq*qk,o0+bzx.v; 7ef -lvround a circular path to have both centripetal and tangentialk-0qk b0o *vzq-x;v hmet.k,ycl+f7f acceleration?

  The gravitational force between two obje z xqk*,me;8kq-7ncpfcts is proportional to

  The gravitational force between two objec.8f6or8jaj 6f jf+llcts is inversely proportional to

  Two objects attract each other gravd* *y/j,00pqkji o/o ss:gqdritationally. If the distance between their centers is cut in half, the gs/0 d/qsd : o* ,iroqj0jg*kypravitational force

  Two objects, with masses -5s0xi pr4 ipynr+ch4$m_{1}$ 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 mass eo+nq-ab,6 jpeqs( 8ies $m_{1}$ 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 oaw 7pp;u -0hxwf universal gravitation.

  Compared to its mass on the82 j50vqcbvdqp is/,r Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is onek 0kf7 hp )fzfzxt13r yamc.-5-sixth what it is on Earth. An object f0h7f y1m5 xctzpfkz3 )a.kr- of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth6g )wd c9-nkmxrtck(je.(u)bj88edh's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull of Eq 5 s dszhv*+lnj5ccshx*)o- n984nhiarj z4dhnh-c 5q*xnov)9ssi5n+s*8 c lh th's gravity?

  Suppose a satellite were orbiting t qrg 0zgvfb0z;ym2b(5he Earth just above the surface. What is its centripetaq rmv yfg00(g b52;zzbl acceleration?

  A hypothetical planet has a mass of half ta:q 6.k lsmw8yhat of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity okq8y s la.6w:mn the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth xo7x+jvq -nr8 what it is on Earth. The radius of the Moon is one-fourth that of the Earth. 87q v-jxn+orxWhat is the Moon's mass compared to the Earth's?

  Two planets have the same surfacd( 0r) )aamzkz(2 nadbe gravity, but planet B has twice the radius of planet A. If planet0 (z a)bdr z)k(andam2 A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet 4aeypzt 8/ p;cf 62q74nodnq tB has twice the mass of planet A. If plan ;/p 4atnzct8q47 n ypeo62fqdet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) abo u 15d4v- o6nljw*lq5z m9pqqout a spherical planet (qj*lq5q9m6nvd4lu -o5po 1zw mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the 68s8sd5 mfyi q9-o6dgqrx4h bsame orbit. Compafsdhrm4i6 9g5y88bx s- q6odqre the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Co ) e8orccczv f5vojk;)s/dy6.mpare thevrsoec. yk;5/8oj)f)d c zc6v reading on the scale to the person's true weight.

  Who was the first person to reali1cprds kv:ng.(0a4t aze that the planets move in elliptical paths around the: drsktpv 4.g (a01nca Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around th:c81svb.onsw ngxxtlh6i 6ttqyx) e/-m .8e 0e Sun,8..sbx6om 0q xnxt 1)8/c -vtwhetl:6ngiesy

  Let the average orbitaoo5pp3. )+p5zw/ vnyqx el v)zl radius of a planet be R. Let the orbital period be T. What quantity is constant for all planets orbiting the Sun 3zzveo+5y5n/) xpwl popq)v.?

  A planet is discovered to orbit around a star in the galaxy Andromeda, with the+lu604y4d3x h a2 sh7 kyng3y;ajy;fkw fx/sj sameljsf axy whyxy jy k/;s h0d4nf3k;2+7 gau364 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 tn34jw-) 4hsf wxf9r xvhe Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. Wha f4 39f wrxh4)-jsvwnxt is the asteroid's average distance from the Sun?

State Kepler's laws..( yche,kphb/

  List the four fundamental forces in y c1xotyr9n8ow)(ec 3nature.

  An object moves with a constant speed of 30 m/swbhzsqjdlm lt :-q k,5;9d6,k on a circular track of radius 150 m. What is the,-,skl ;q9 :bjqtd6 zdm hk5lw acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h gr4na0 kp8tp*2wjit7 . What is the maximum speed around a curve with twice the radius? (Assume all other factors jgpt8 704pnw*i art k2remain unchanged.)

  What is the centripetal acceleration of a point on the pertd;oc5 sffz2 +imeter of a bicycle wheel of diameter 70 cm when the bike is moving 8.0 m/sf dt;z+focs52?

  A point on a wheel rotating at 5.00 rekli a(:hg(7 2c ymx6lj/.:nckmsr z b.v/s is located 0.200 m from the axis. What is the cemng lbxh.al2/j6:(7izmky kr:c.c s(ntripetal acceleration?

  How many revolutions per minute must a c.r ab*gmmkbn 71- a4hyircular, rotating space station of radius 1000 m rotate to produce an artificial gravig-n7yrmm4*a1 bakb. hty of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes aroig+k1ihm 8u4hd q-,dh und a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcyh,+h 4 kui1d8i-qhgdmcle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is0at zj+ gie.)d whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum seja+.zig)d t0peed 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 vertica61r9oi)nh sullk:;l2o/l t;k ltlk)d )6bz fxl circle of radius r. At the ext6t b6 oos1dlf2lzu)hlr)l: )/n9lkk ;ilkx ;act 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 lz*vpc cej97 u*gte 7(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 9cuzcpjge(*7v * el7t 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 acceleration of 4g whrw,6;o cqs 7 9:xjh 0ar0;ulvg,irp mden pulling out of the dive. What is the radius of curvature of the loop ini: m0 wvr pu; l,j6qh7;ogracx09,sr d which the plane is flying?

  A pilot makes an outside6n: )tpim.s ,+- ifqggovy(8sn/z ikb vertical 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-hanti)nvs bgy+o kpi f/8.smi 6,(-qg :zlf of his normal weight. How fast is he going?

  The maximum force a pilot can stanoj,1-w dd5fc bm 4v4gnd is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out,fjn-1 dd4c5 mgwvbo4 of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizonar5n4vbgec . o2-if 2ytal curve with the tires on the verge of slipping. How fast can this caro5. 2i-grn4vbf2ya c e round a second 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 with ap t+zh3x9r x3m speed of 20 m/s. The centx3h3m9x+pt z rripetal 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 must btg, 9ifxxd: f4lc a09se the minimum coefficient of friction betxi9fd,s lf9c tgax4 0:ween the tires and the road for the car to make the turn?

  A car is moving with a constant speericf4d+ /ke 2bd v around a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum ekfd24i+b/c rradius of the curve if the car is to stay on the road?

  What minimum banking angle is required for piw+3d*zl-itan Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ign*t+ip3 -dwzli ore friction.)

  A horizontal curve on a bobsled run i6w l vqfz.s4ykjuf1hd66m / k-s 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, banked3bzc.cu 1 *flx at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m ishr9qj y7lfi9. 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 s..gn /rbi ngs+qqlk rhlt5)3; tring is revolving uniformly in a horizontal circle of raht;g/ q)5n r.blqgn3 r+isl.kdius 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 a6 h+wb+d /p5 )xynj,+bnmjtr nccelerates at a uniform rate to a sp+p+6j+tn bn)wd yrj5 /mnb x,heed of 45 m/s in 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 consist0:7vilarfr8 (g p ,lruk*.i yjs 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 on a 70-kg person tblw+z)e(xd753 4h3 hbwjcr v standing on the Earth, due to the Moon? The mass of 3h7lbechv 4+r(5w)d t3xjz wbthe 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 vm7 ; +ijm cylz.7nhb4g )i7fdnjk.0k masses are moved to half of their initial distance, what is the gravitational attractive forc ml 7 k.f4nj 7+iz0g;)k mvdy7nbhi.cje?

  For a spacecraft going from th 0g oa6sclik7z8(wj1l e Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the E 8ag(wc 7i01slkljzo6 arth 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 isg ut)o /tdt-p,wk fz,zu8h(n9 $7.4 \times 10^{22} \; kg$ 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 "spaj.tmcwi 93 a3 f6ivt,gak0nj5ce-walk" at a distance above the Earth equal to the radius of the Earth. What is , 3ia cifgjv6.nmtt5w9jk3a0her acceleration due to gravity?

  The radius of the Earth is R. Agd:v mxmj o4+fnao)89qq gok 9u6yf:.t what distance above the Earth's surface will the acceleration of graq: o9mu9oo mj ff6.:xqyv4k8)gnag d+vity be $4.9 \; m/s^2$?

  A satellite encircles Marly:g doj.n0 a8s at 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 gravityndo08j :gl.a y on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of ge d -ngj(g:em bdb0dl /8*t*mbravity is nm j* - d(egdgbl08bbmed /:t*$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surface o3cp 1se)o z(dh-q2brzf the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, whats rp 2hb coq-13()dezz is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes fk22 pnjbr0w s6 rx04cbrom sea level to an altitude of 5000 m? (The mean radius of xw 0sk02cjb n2rpb64 rthe 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 the 3eslskx ufapg lkd*/+4 5c0g1 Earth's surface. What isf x0g5us d*p kalec1+/ls4k3g the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice itq fa- m/sc9-4pm vi7kxs radius. If a jar of peanut butter weighs 1m9i/kxq7 pv-afs4cm-2 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 asexo fyo2zd2y27b -4hll lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mas7oy4sdhe yz2o 22-xbfs 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 l-lx4+hh mkj;is 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 low circular ,) + qlq .naashie 9; bh)w-tdafsx+8oorbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (Tha), )i +.qtsxd -ao+ na8swlb9h hqe;fe mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit a4vr7*vi ,txdobout the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution aroun4d7r , v*vtoxid 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 s- vt,9o.wa*bks5eresf+ 5f.g+ yx lwmurface of the Earth. It is observed to have a period of -l.+9+*e5 xmarg ,.b ekf osw5fwytsv89 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,v mqo6llq u8 /b).hj6z 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 radius z4a7jxya i +af/h*gn7ihh4 3kof $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a planet in nearly circular orbits. Moo 2k o/o3 t9bgo vv*qhqy1ped30n 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 tov3evto1y /3 ob*h 2pqqdgk9 0ake moon B to complete an orbit?

  The planet Jupiter is**yhfj :+ish p $7.78 \times 10^{11} \; m$ 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 yearrd0c)8 cz3scys to orbit the Sun once. What is the average distanc 38 d0czrcycs)e from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)