Is it possible for an object moving with a constant. rot2an0: u;u8tc erz speed to accelerate? Explaiu082.on a:ztr tcr;eun.

  Consider a particle moving with constant speed such that its acceleration2 ysnz/n p8jk9 of constant magnitude is always perpendic2n9/j8skp n yzular to its velocity.

  An object moves in a circular path at a constant speed. Compare the direction92alov lti u0ban6j+ckwnx7 d40+n*t of the object'tw 7an nnx+abj v9 ilo 6ukt4c*00+d2ls velocity and acceleration vectors.

  When an object experiences unf*.v5yo ahd va w:1kn-c.h+uj iform circular motion, the direction of the acceleration .kuf.h15ch awvovdy- + n*a:jis

  Consider a particle moving with constant speed such tha f1q rkdzd0w r5.s.*v*f3hu hbt its acceleration of constant magnitude is always perpendicular zruh.dh1.5w*b30dfsk vfq*rto its velocity.

  What type of acceleration does an object moving with cons rsotg/z053c rtant speed in a circular patr3 cszrt/ 05goh experience?

  What force is needed to mak) l,5mh) gazq hhh9iz+e an object move in a circle?

  When an object experiences uniform circular motion, the dir* nwq pj/7uxd/a8:k4uje,m9px 9t rcwection of the net force idutnmx9 u,epqk/c498j pa: 7*jxr ww/ s

  A roller coaster car is on a track that forms a circular q8iao)i- 7skmloop in the vertical plane. If the car is to just maintain con k)-ao7iqi 8smtact 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 track that forms a5bv uv8+6:x3cw cam /oi;tnjh circular 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 uic5navt 6 8mjh: vb;w+x o3c/its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc until i koi0 q-6+rfh+fwe* cpt is going straight up. Just as the plane is at 0hrc-k+i+*w f eofp6q 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 curvl4j +lb(/fqm ue 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 constanp4 pj+2lirzzb +*4 sg)b4l b z1.zkqwst speed v. Then it goes arounkqzi s z2bpj* l+ bs4 rzz4l4p).gw1b+d 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 time, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it xo6tm;uq29im /1t 1ia7noh;l6 ynt segoes around a curve of radius 2r at speed 2v. What is the centripetal force on the c29;l7t neoo a1ytq6;n mi6hm/1txs uiar as it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r )s-g)zec br+: b i1opmwith speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizon))b rcm1g ozsbp+ e-:ital 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 the same angle, but ond* yl*- jpko 38fq569bmrjg2wf4 tnoje has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius 4o9mrj*j3k* 28t p6 ol5 jbwdfygnqf-curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bob 3n3wg)fqayb9 yzy1j6sled track is not 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. Why do they do this?aw yyy1b93nq) z3 gj6f

  Is it possible for an object moving around a circula*uc.oh bo.:u aa91xnw m-2cunr path to have both centripetal aua:xn9bwau co1.2nmhc - o *u.nd tangential acceleration?

  The gravitational force between two objectp 2ck/a9vhm3 f xdqwnop656c7s is proportional to

  The gravitational force b(vm.dhcxf v 9:etween two objects is inversely proportional to

  Two objects attract each other gravitationally. If the j+ 6hwwv/6h8 6wzfuszdistance between their centers is cut in half, the gravitational fo+zzwh jw6s68v6/h fwurce

  Two objects, with mas *sll /5x)xpfyses $m_{1}$ 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 massesjunta*sr (3* nb pyb175qfmn1 $m_{1}$ 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 gravitaaib htx)kfbd x.rwxzgx 5*0bj4;47 d7tion.

  Compared to its mass on the Earthwymf 5.)j-e x7zuyow o83;vtl , the mass of an object on the Moon is

  The acceleration of gb2 sf5c g3.hqkmlezal1 i z5)6ravity on the Moon is one-sixth what it is on Earth. An objects khml 1iczfgb5) 36le5a2.qz of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's)c/xfe mk8vg m/l18 ls surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the 0 l5d0cgyti5j pull of Ea5c0 tijd lyg50rth's gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What isti j0z792rkct its centripetaz j92ctir0tk7l acceleration?

  A hypothetical planet has a mass of half(d (b msq;aypn2e8nl/ that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due ;pb(q /ysna d(8nm2elto gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is.t2x5tag/wt8+v/ *w fjznwo xlu+wppf9 iu )6 on Earth. The radius of the Moon ixx*vuw5wt/wfupanil) j./ ofg62+9 tt+z8wps 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 has th2y8h,d(ts*/y qf ojc3) btmswice the radius of planet A. Ishf) d/ th (,* soc3q8my2ybjtf planet A has mass m, what is the mass of planet B?

  Two planets have the same surcazwbda.; l4 .face gravity, but planet B has twice the mass of plaw az;b.l.ca d4net A. If planet A has radius r, what is the radius of planet B?

  Consider a small satellite movingpu:1 0cdp9oid in a circular orbit (radius r) about a spherical planet (mass M). Whip d1c0uoi9pd:ch expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. C-9 kavr,2ibdbompare the two sat d9-ak2,ibrvbellite's speeds.

  A person is standing on a scale in an e x y1k*q( b*yii,bs*trlevator accelerating downward. Compare the reading on the scale to the person's true weight.(ybybi i*kr1 *xt, *sq

  Who was the first person to realize that the plzyxdvog +/v0(f.r )zqanets move in elliptical paths around the Su)0o dv/x(fzv+ .qyrzgn?

  The speed of Halley's Comet, while traveling in its elliptical orbit around et46rs, 0v4 rl9vieyq 7:3kvcra- l kithe Sunkeer ca6-k,0iql: i37 y 9rvv4 v4ltsr,

  Let the average orbital radius of a planet be R. Lt0w nzk s;;spn,;2v mget the orbital period be T. What quantity is constant for all planet0;k mgvn ntp2;; ,zwsss orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, -exy 0g, vrt/0g 1dwbywith the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass oy-v y,rxg1 geb 0/0wtdf 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 s;kwvjc qfi/a2+pr9. Earth to 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 average distance fro w 2+;fp.skcaviqrj/9 m the Sun?

State Kepler's laws.i -4xy1 s 4zxmpvbs7 j8z,fmh.

  List the four fundamental forcv ppkx 7u/d1w;es in nature.

  An object moves with a constant speed of 30 m/s on v,f3lc 8ybks1.1q n (wq)pwsba circular track of radius 150 m. What is the acceleration of the vpfq ck1s3y. qlw1b)(sb 8w,nobject?

  The maximum speed around a level curve is 30.0 km/h. Wha- j n /mg;i;8k/dz.6x hjzqhhsxd: kt1t is the maximum speed around a curve with twice the radius? ; /x hhngd1 skj8:mz/qt;.kjxz-d6hi(Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimete3 0ehga r34mqbr of a bicycle wheel of diameter 70 cm when t30qrm4h3ag behe bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 6q8fp( wzt6 pbxyea ::8b2 8w/fbph hcm from the axis. What is the centripetal accelerati8wfp 2tca/yfh8e6bp:x6b p:qzh wb 8(on?

  How many revolutions per minute must a circular, rotating space stat juwjs7,;du ;lji0*, g-ppiuwubg*;sion of radius 1000 m rotate to produce an artifici u 7u j ; *udpljwp-g;bw,;uij,0igs*sal gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn a1fa:zc l; /nov yr-,;b0sfa ngt 96.5 km/h. What is the centripetal force on the motorcycle? 01;or:v anb/lnsf g a;,z-cfy

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whir-t;e0pkexgk c()-iph led 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 string cpe )x;0ep gk(tki --his not to break?

  A stone, of mass m, is attached to a smwn -nas+ f :( l14*eljsus3dqtrong string and whirled in a vertical circlea(ls wlnm1j *f4esdu3- s :+qn of radius r. At the exact 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 to a.s (w)tsgqh1 0u xhiq4 strong string and whirled in a vertical circle of radius r. 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 byx 4ihqhtwg0su 1.qs()

  A jet plane flying 600 mhw6lclv vsu/j:s ,*./; ga any/s experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of t/ *n;yw/lj,saavlv s: c.h ug6he loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of lyahz0z)1hfp w 1--dlthe loop is beneath him) 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)hl1d1-y lh pfw-0zaz is he going?

  The maximum force a pilotw29 /bamo w+btpan x,7 can stand is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can to9mwxw/,+na bb 7po2t alerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with the tire -s ad*jirb66o(kjsm-s on the verge of slipping. How fast can this car round a second curve of radiusbs m6o-d j -ijk6ar*(s 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 a speed of 20 m/ r-4owzzo hi::tq4l:vs. The centripetal force provided by fri4i:to- wvo rzq h4l:z:ction 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 qkxl5tcd f6t3nt+a c-p4p 2o./s. What must be the-on. ak p2d ltf3+5qxtct64cp 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 leve3lakou(./sr9v5 dsd fl curve. The coefficient of friction between the tires and the road is 0.40. What is the minrso5s(f3 d/uldv.a9 k imum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled tyakrp h1;2ne z.t wun 201(gvwo negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fricw2e 2a ugt1r1z wh.vn(n;p ky0tion.)

  A horizontal curve on a bobsled run iz d4+ed4 2z98y5 bxsfdb-pe ess 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 atqgc1*zv0wyk bl8pj- 7 an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 5ugjka 9-( l+vgzch0wm is 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 isyhg26sd:hh qkpcea4 -.brb;0 revolving uniformly in a horizontal circlcs:;bgkhq-0 rah4.d e2 p yhb6e 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, a race car accelerates at a uniform rate t nr 7-gcdv(y(mb35no)w h.k yjo a speed of 45 m/s in 15 s, moving on a circular track of ry (bcnrk ygw5n j.o 3m(-7dvh)adius 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 consf(9lf z 00r yuuofwvt( j.(c9qists 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 s;0meg* .o9ryual7awvbp 5 yw5 tanding on the Earth, due to the Moon? The mass of m.;pgw0yauvo* ywe 7r9l 5a 5bthe Moon is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attr l v+:7(uzn/euxpv(i )a xvap)active force between two masses is F. If the masses are moved to half of their initial distance, whatviua/upzv)e 7p (x: +n(vl)ax is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance frorv qhlgsl *j ,nzz;.+8m the Earth will the gravitationzl ; qv.jh*,sz8l+rngal forces due to the Sun 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 is(7k p; n9nf9 yrx;,a)mpyty hh $7.4 \times 10^{22} \; kg$ 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 above the Earth eqm5 ujf5j4rnkr hr jl*4io2 wu2i*6n 5yual to the radius of the Earth. What iif u5 kmu rnn2wr4 jj24io5jl*6ryh*5s her acceleration due to gravity?

  The radius of the Earthaiv lp//buobku048rgx(an +rj;:hh5 is R. At what distance above the Earth's surface will the acceleration of graviturhbi0ak (l/p vr:j+h/na8g54 o;b ux y be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times o3g6aphupu : r+boq3/ the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of g:aupq6o+hop/b3ur 3gravity on the surface of Mars, is

  At a distance of 14000 km from some plahj38px0b j- uanet's center, the acceleration of gravity a80b jhjpux3-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 thsqt you) ,b7h(e surface of the Earth. The Earth has radius r. If the object is raised to a hei)u,hb( y s7otqght of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes fromb5dd2s:ljwssb51 jc bx/b q 2- sd5ldq2-j b sj5:b sb1b/s2xwcea level to an 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 5a+tf8l6m0wn -v ke deyuzr*o5cb h06z4)xcgmass 100 kg is at a point 3r above the Earth's surface. What is the satellite's we)6ek 5z6drv0egf t 8lycm 0 +hc*ozxu 4wa-nb5ight?

  A spherically symmetric planet has four times the Earh 4ke4v3ks0 v ab7 a.k/rno0qjth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the7sq ha3v.40kno/ke4ab jk rv0 surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, jy18 kbqcv2 5tni,5 3 fjmdwk/and Sun all lie on the same line, with the Earth between the Moon and the Sun. The M2,j8q 1y dc/ b5fvmnktw jk35ioon 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 ballamb 6zupb 6 t4apytt1-m.aqafi0x 52- 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 orbit about the Earth (i.e., it juskss/hehpynk.9it (8jo 10w;bt skims the surface of the Earth). Wh1/wh(kb 80kpone yjhit9 .ss;at is the speed 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 skims t ozjzg1;n7;*vqd 9vl xhe surface of the ;;vo vzd1g 9 jqn7xlz*Earth). 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 ofi5 i4d7*/vooz;y d2qxne e+ fj the Earth. It is observed to have a period of 89 m/d4; ji5ve* o7dqyexz n+2oi fin. 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 a ,; g5ctpg(dazn 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 Jupitek1(()balb h/s2y 9s5 z olmevd2tjbn- r 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 u+n c4j*jk5ir wf..qe circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takejnr*f i.wcq.5 +kju 4es 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter iszy)t60 a gz r3n;bu1rt $7.78 \times 10^{11} \; m$ 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 c2uc ec5t+y3vonce. What is the average distance from Jupitt23cycu5cve +er to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)