Is it possible for an object moving with a : ojoje fbux:(o5d 9-bconstant speed to accelerate? Explai e:bo 9(b:5fu-jxo odjn.

  Consider a particle moving with c-:d8wd0 xy 6kcmc)mzuonstant speed such that its acceleration of constant magnitude is always perpendicular to -cx uyz)d6c0m8:mw dk its velocity.

  An object moves in a circular path at a constant speed. Compare the direbumhu37ye ppd+q109grrt v5* ction of the object's velocity and accele d5mbp 31t*+vr9huuqr07pe gy ration vectors.

  When an object experiences uniform circular motion, the direction of the acce*b22 a+b n xxjbrre;b,ler rba2n2;xxrbe, *+jbb ation is

  Consider a particle moving with constant speed sulwg 296 kveib:ch that its acceleration of constan bk9vi26:wgelt magnitude is always perpendicular to its velocity.

  What type of acceleration dogqcp ynqb/t .ip9r/-u 5,;iqses an object moving with constant speed in a circular icyn ;5 .uibq,/sq/qpr -t9pg path experience?

  What force is needed to make an objest 0x co:vvta.ow7(t/dxq ho2s .6 9axct move in a circle?

  When an object experienctvp ev ,b6(,rqjt0;fies uniform circular motion, the direction of the net force i 0i,btvq;t, (ejrfpv 6s

  A roller coaster car is on a track that forms a circular loop in the ver;f:n,z vzrgojpf571 t tical 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 acceleration at this poin15vz, gpjrz;:7toff nt?

  A roller coaster car (mass = M) is on a track that forms a circu)gkh1 l4z hi2nlar loop (radius = r) in the vertical 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 pohg2lk4) nzh1 iint?

  A pilot executes a vertical dive then follows a semi-circular arc until ujew3 w -1x kw4 gox0qhb:1u7.xkmk a:(hzp n*it is going sth*4knx3wj7u (b wox 1ua:k1p-h:ekqm x.zw0 graight 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 curv /ccys /4ml ob9qc2. n7,kztmae 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 constan -qefn9e yo*o;t speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on enq;yf 9*-ooe 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 cok) a3twiwk ld eyh,7t* y,qr.3nstant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the cenyk.wwy* 3dhatqe3it lkr)7,, tripetal 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 wi:djp 8hjixa3+2uj-u 5wx bmiovrrf1t91 -za. th 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 from the road is equal in magd-uru-1jx fa vj:a8ixhwj51.tr iop3m9z2b+ nitude to

  Two horizontal curves on a bobsled r7ch79k9l fok ;;grw yrt;)dhuun are banked at the same angle, but one has twicew)7rt ;;rl99yugh kokh ; f7cd 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 curve?

  The banking angle in a turn on the Olympic bobsled track is no7g2 f5yce**2ehjcg hk9 frj i((w/wah4 0axtzt constant, but increases upward from the horizontal. Coming arounct /2jh ckf 4ww(f57e jax(rga92*hz*h e0gyid 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 around a circular path to have both centripe rm+x u9x 88:4niy9(rtk a* ,baypliaxtal and tan9xy8 ranra lyx9k+i,a xmb(*i8p t:u4gential acceleration?

  The gravitational force between two objectsx32cdwi s- n9g is proportional to

  The gravitational force between two objects is inc-aytsy5q :0 gg b1ckd 3+d)dfversely proportional to

  Two objects attract each other gravitationally. Ip:-9f6uq:v( b 3velklxyi y +zf the distance between their centers is cut i(p9:zl v veuy+:yb xflk-6q3in half, the gravitational force

  Two objects, with massesq h )fu(e2fwye2u /zoh:t(m3v $m_{1}$ 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 massespj58ri rpn4k0s(w omsz q 1y3- $m_{1}$ 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 unive*bj1;piv-fi:xf w s5) o*vsqgrsal gravitation.

  Compared to its mass on the Earth, t 7v pil/-vfhmq7z+t.che mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it ib 6dzo6ucf(pmm ; g(2as on Earth. An objectbap f mmc((gou26z 6d; of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's weig9v5xp zle-2bu m9qtq aa)zh-; ht

  A spaceship is traveli p-1en2jrwqgh6uc )a c46si8 ang to the Moon. At what point is it beyond the pull of Earth's graj-n 8 gcr 241a6hewsaq6pu )icvity?

  Suppose a satellite were orbiting the Earth just above the surface. What is it9jb+ y:/oyyo g by(jw2s centripetal acc/oy j(bgw jy9 b2yy+:oeleration?

  A hypothetical planet has a mass of hl.5jk6 e2wpr,62ekgc7 re m kpalf that of the Earth and a radius of twice that of the Eag2 krkrp,.c6l me 26w7kpj5e erth. 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 on the Moon is oa7s9vo-e+:fni ra xg)ne-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mxag 7fiesro-n va:9 +)ass compared to the Earth's?

  Two planets have the same su) rkh.d:(er s truy;czhko52-(k k6qwf:wui1rface gravity, but planet B has twice the radius of planet A. If planet A y5rrtf.ko;rqw 2u 1 k(w:h(cuk -6z:) kisdhehas mass m, what is the mass of planet B?

  Two planets have the s a -h 5o(7e/kcypg7+/hmyeeu iame surface gravity, but planet B has twice the mass of planet A. If planet A has radim/ e7 ghi kc+y5ee/uoh7(ay-pus r, what is the radius of planet B?

  Consider a small satellite moving in a circular orn +,,pt)zbpt c8l nsr.bit (radius r) about a spherical pl ppl8rt),b.,ctnnz +s anet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B,;xr+ d4u9sp;xn1x4ta .ngtmy and rotates in the same orbit. Compare the two satellittxdyxn+mpa ;94 rnus. gt;x41e's speeds.

  A person is standing on a scale in an elevator accew,19xqe7l j1tm qh9jvlerating downward. Compare the reading on the scale to x 71the1l,jqvw9m qj9the person's true weight.

  Who was the first person to r;e us1(ldm-w iealize that the planets move in elliptical paths around the Sulu-se m( ;dwi1n?

  The speed of Halley's f8j: 3z3u, ngelss5g,8rt7fd v ydw;z Comet, while traveling in its elliptical orbit around the Syn: 7835egws ;,3vsdfugljd fzt,z r8un,

  Let the average orbital radius of a planet be R. Let the orbita1kzn8qc1ym 49y)z qf bxi**sl l period be T. What quantity is cony9z1m i *)qn c8sfbl 4y1qz*kxstant for all planets orbiting the Sun?

  A planet is discovered to orbitt 1cu8boi9q dh:)x2 fe 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, compared to the Earth's orbital periodu qot8fhc1 e)2bx i:9d?

  The average distance from the Earth to :. qf+hhrilyw/m q6u8the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroi.hq 8umqh+ wl/yif r:6d's average distance from the Sun?

State Kepler's laws.xpa,kkw iq9) ;

  List the four fundamental forcesl0 gu9*g,a*muvr p jkdnre+ 47 in nature.

  An object moves with a constant speed of 30 m/s on a hnki)m5 wz 2xwz .-c+ t+ur;umcircular track of radius 150 m. What is the acceleration of;+r mn2t uhkz5mzw)c.iwu+ - x the object?

  The maximum speed around a level a zy9x/d9g)qc fh mw7(nr/+ jhcurve is 30.0 km/h. What is the maximum speed around a curve with twice xmary9+)d7 cw9qhfz//(gjn h the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle qw1p s9l. 6o-yzoizc..z8 m 7g6it ihfwheel of diameter 70 cm when the bike is movs goz iw.f7o6hi ..mzq6 91l8tzicy-ping 8.0 m/s?

  A point on a wheel rotatingl0ti6 / xtt(zg at 5.00 rev/s is located 0.200 m from the axis. What is the centripetal accgit/ ttzl 06(xeleration?

  How many revolutions per minute must a circular, rotating space station of ry 3 x+8a zzex5qd:4ftjadius 1000 m rotate to produce an arjzef45xq3xt +yzd:a8tificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It ws5mx uo *f)0 rfa/ 6xjd(j2bzgoes around a 13.7 m radius turn at 96.5 km/h. What x)5*xfdsf(mj02zo/ ru6a w jb is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the cbkh3n+ 5:7.cx3 ojc vf qfjkbc8 ,4rbend of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the stc,xkfckqb+8c4 v 7fbnj3.oj :r5c hb3ring 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, iadlcab)2 y/8)pbhi,ns attached 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 thy8,bnaacl b ))dh2/ip e stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is .7t *l)s3 xb+tpns kiuattached to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the l p*.b+isktn7s t3ux)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 acceleration of 4g when pulling out of6(;zs a buy, y/3trwqh the dive. What is the radius of curvature of therzw,h/tyq(u6 s3 ;bay loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop is beneam bk esy,r8n,,th him) 8bryk,,senm ,of radius 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 s 9h ifhe,sz/2itand is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out 9i, ez/h2fihsof a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radiuspw-g 2u,x;ee; my+*o+e htf ad horizontal 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 surgtf;w+ epx,eu*o; h- m yd+ae2face.)

  A car is negotiating a flat curve of radius 50 m wit r*qbr 3 r0p44ek/xpv*ptw6hth a speed of 20 m/s. The centripetal force provided by frip k 4r* v3he40/rq x*tpbrwp6tction 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/s3 nwl5/f -5jdxe8w+;jof avg j. What must be the minimum coefficient of f538jgo5lwf-jnjw ad+ v/ fex;riction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. The coeffici vm la/ijg8z/sz l*1go9g/ny8ent of friction between the tires and the road is 0.40. What is the minimum radiuoz9//ilgnl8sy8/ggm* z 1aj vs of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negof. mi:9 w6 i7;xth00t1qjgqgn ylkw 8*v,w uectiate a 100-m radius turn at 35 m/s without skidding? ;9xtnuv:wg 71fq6h8cw ew0kqmjyit,i0* l .g (Ignore friction.)

  A horizontal curve on a bobsled runs3our4uaf y6duy+f7b :f ye +1 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, banked ea x*bmtl8*3ko/ w8kg g9 4aglat an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banke q+;o+ntw1 h ;yvdi.vuhw )4lkd 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 revolvinn:wmy zduj2c /rv3q0 u di p5m2*(yj8zg uniformly in a horizontal circle:zm d y08j2dmcv3 jur(/z ipnu2w y*q5 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, a5egq,.ewx8;r(e nd h c race car 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 fill in numericalehewdr8gn c;.(, xe5q 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 n 9 mq0s ml,1ctu4hd 7jkrc-+ia 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 on/rv i0,a jvjw*r8)9w c vwel;b the Earth, due to the Moon? The mass of the;re 80a ) r9w*lwjvc/ivbw,jv 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 ;y9r mk/ujf+y ht,7qu* jhlf1two masses is F. If the masses are moved to half of their initial distance, what is the rymh u+1/jf tjf* uq 9,7hy;klgravitational attractive force?

  For a spacecraft going from the Earth toward thu/7r9vud /rk m 7i.ihhe Sun, at what distance from the Earth will the gravitational forces due to the Sun and tuk 7dm./u vhh i/rir97he 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 isuqv z7,zebd0 o/af 7i(z,x8jb $7.4 \times 10^{22} \; kg$ 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 ab qjuxllkx5pk7)f : 58move the Earth equal to the radius of the j f57u) plk 8:lxqkm5xEarth. What is her acceleration due to gravity?

  The radius of the Earth is R. 3b*y vp)qp)it At what distance above the Earth's surface will the acppib q*)3 t)vyceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equt. j hm.r;f+b 2mglhw(al to 3 times the radibf (rg.;jwlm h htm+.2us of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, th4q/o1ksv b5 hde acceleration of gravity is /4s1ov5hdb qk$32 \; m/s^2$. 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 tl*sy zf6t,td0kxo5hvc)q5 u 7he Earth. The Earth has radius r. If the object is raised to a height of 3r above t5fk)xs5c6dhq* ,yul 0vot 7zthe Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person chans(w ul 2hl-t+cge when he goes from sea level to an altitude of 5000 s+-ll2( w hutcm? (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 poigavcr9l2 x6-7 zyxvwu. z(t*p nt 3r above the Earth's surface. What is th 2cv9zxa7urlx*pw6gy (vtz- .e satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twicezj0u5, a km1wn its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would i 1w05mz kau,jnt weigh on the surface of this planet?

  During a lunar eclipsin.-:cs n( lht;nh,mh ev03yue, the Moon, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mass ofle(u:;m -ny s3tcnhi,n0h.hv $7.36 \times 10^{22} \; kg$; 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 e 19i.,docq64uhy g jhthe 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 orbit abohnwof*e8g0- uzk g-.dut the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The --gd. fuwk*hzn8ge o0mean 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 ilcegv35w) wwd)a , 1pskims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean radius o)3l ,wci pgewva5w1)df the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Ea iuy7fc 2hc*v hb;59njrth. It is observed to have a period of 89 min. What is the mass of 5cf hb 7nicu 2j;hy9*vthe Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an k6uh 8/d:4 yt:qwszodorbital 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 plane9 sush07mbtf5 t 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. Moon A has orbitaly30h0 y zqjm.n radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon j0yy.q0z3 n mhB to complete an orbit?

  The planet Jupiter is yr ciel ue7g;gq:*;b-+(i hun$7.78 \times 10^{11} \; m$ 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. Wwlb7ii7e r5(hhat is the average distance from Jupiter to the Sun? (The drbl5 7(7 wiheiistance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)