Is it possible for an object movl6jezuu2m2 n :ing with a constant speed to accelerate? Explain.2:nmj2uue6 zl

  Consider a particle moving with constant speed such that its ai s00xsauzj3q .6 o6ixcceleration of constant magnitude is always perpendicular to its vu 6qs0ijo a .xzi03s6xelocity.

  An object moves in a circular path ahbb-91i mak3w.ldke8t a constant speed. Compare the direction of the object's velocity and acceleration vectk b l-mw1d.h8baek9i3ors.

  When an object experiences uniform circular motion, the direction oly;tmt,z aa-3 f the accelera ;a-l mtza3y,ttion is

  Consider a particle moving with consos(8ec* ;--ks x9dcn .nive;cs5deh r tant speed such that its acceleration of constant magnitude is always perpendicular to en9x;shec d (8 .ek crs;n5*ocd--ivsits velocity.

  What type of acceleration does an object moving with constajx6g9u7 e 0k ;+bf ar*c3ayhyynt speed in a circular path experieny;cu6yx fkr 307+*h by aej9agce?

  What force is needed to makjfmgcoyp :4knhyn :7kr633p 6 e an object move in a circle?

  When an object experiences uniform circular m ivc,8* zatvv ytmz(w8 3c:0tlotion, the direction of the net force i,8tvv8z0tt(ic*:a lczm3vwys

  A roller coaster car is on a track that forms a circular loop in tgrfcqob5g2iku2. c(1 he vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value for5c. 12c ur(gbgqkf 2oi its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a u66z7/fm(2t(kboz0:5cdwle xb n,6tea qosytrack that forms a 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 val:xuemo670l ( 5wtb ,cysbn a(2kz6od6zq /fetue for its speed at that point?

  A pilot executes a vertic z;kui4k /e-vfal dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the fore kz;k4-f/u ivce 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 radifp65d/onp rsh4m+hy2 kuhl: 0us $r$ 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 constt+qq vmc us073ant speed v. Then it goes around the same curve at halfq3uvc+ 70tm qs 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 weezhe3-o9 e mco , qymt8n7g7-pfd+- v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as gq-7wem dtzp e yme fo,+en--c798ho3it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of rar py7a1 g g271lmx/rncdius r with speed v. If the road is frictionless due to ice, the car can still negotiate t1cgrxpl2mrnya /g7 71he 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 the same angle, 46:)vujvc rf rbut 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. W4u6 vj:)rfcvr hat is the safe speed on the larger radius curve?

  The banking angle in a turn 3hgmzjx2y/sf sx6;8ci 47 zraon the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a t4shcx7; j i83f2z/mgzx a6rsyurn, 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 c :3df z)-4 ot*wrjwenventripetal and tangential accef:4t*v d3 n eowrzj)w-leration?

  The gravitational force between two objecw c)alk ml+w*qs2 84y :n ga5*zh;grrtts is proportional to

  The gravitational force 1p;71qaziaq lbetween two objects is inversely proportional to

  Two objects attract each other gravitatlomezb2w)83r2 z +vr w/v-1tdgda ,dwionally. If the distance between their centers is cut in half, the gravz3ww +bm dwva )el-d ,1/8vrzgt o2dr2itational force

  Two objects, with mas2 th1rc k*jaq8ses $m_{1}$ 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 zc77 n).gs wh/+ e6j1-x,qtzocaus ha$m_{1}$ 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 universnk,590l3*m tbl 1uhe wepury1al gravitation.

  Compared to its mass on the Earcsnozbh81js;0 qgqxr:6: 4u gth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one- ;9tq0o v,zmf45a qnzasixth what it is on Earth. An object of maqtf zoz59 0a,qam4vn ;ss
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away frog7yzatt ci7j8:a5it 0m the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At wha lj;+jm)ve nim*/co/ bt point is it beyond the pull of Earth's gravi * b)ojcnvm+/lej/;mity?

  Suppose a satellite were o ij *jckmvf*r)(m9gm1rbiting the Earth just above the surface. What is its centripetal acceleratiogi*) m1 9rjc*mmk (vfjn?

  A hypothetical planet has a mass of half that of th a6tf,.je trd4 :mn6uxe Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms xtdtm: 46f.6nea ru,jof g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth (n* clvpg-z+7kzeb dyakr3 87what it is on Earth. The radius of the Moon is one-fourth that of the Earth. Whzg8dn-vak*3p 7 z7yckbl+e(r at is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but plafiol6r)n+a1 g *s zs2gnet B has twice the radius of planet A. If planet A has mass m, what igg2alsnifz1)6r +* oss the mass of planet B?

  Two planets have the same surface gravity, but planet B haszn07/y idhwr bo gp /r710gb/w twice the mass of planet A. If ngowd/zp7w/ br /0r gyb071hi planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit kro kt4.cl:fx*-*u ea(radius r) about a spherical planet (mass M). Which expression gives this satellite's oo c-urk *:*ke.aftx 4lrbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the i,, 2u bmb)kvpd,-k7a khur .msame orbit. Compare the two satellite )mbkh2im,,k7u kav-.rb p,du's speeds.

  A person is standing on a scale in an elevator accelerating downward.oo.n;-t+ype) l lvau 2 Compare the reading on the scale to th +ou2t-ep) lynlo;av.e person's true weight.

  Who was the first person to realize that the planets move ind v0st-/y- pv7moke;m elliptical paths around thp7 / ovmkme- 0ys-;vdte Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbitr k,)1 aydblml10m7ly around the Sun, )mbk1ml 17yr0dlay, l

  Let the average orbital radius of a planet be6u ickv5; 2bcwor 58rq R. Let the orbital period be T. What quantity is constant for all planets orbiting the Sunb65vwrqciouk r85;2 c ?

  A planet is discovered to orbitoen3q3rz241 -o uw a/f7bow vm around a star in the galaxy Andromeda, with the same orbital z 1ar/wo-n4oo732 vmqfwb3u ediameter 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 the Eare d68:wozit98dvi.jzth to the Sun is defined as one "astronomical unit" (AU). An 6o di 8z.tei8j9d:zvwasteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.3:nl 21hcs,wnj a ; q(scwqi;yw88ktj

  List the four fundamentaqbg lb;2;i0zp tp58cmke1nn9l forces in nature.

  An object moves with a constant speed of 30 m/s on a cimy,v djyfp8)g-e. 4 /lzbefz+ rcular track of radius 150 mzg)8bdp-vmf e , jy/.e fzl+y4. What is the acceleration of the object?

  The maximum speed around a level curvd*c gbwp 3.)eve is 30.0 km/h. What is the maximum speed around a curve wbw3gvc. )de *pith twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal accelerat uh9lxbr;fp g,*yd o5jdk7q/ ,ion of a point on the perimeter of a bicycle whekg ; pb9xyuf ,dj*,5lrd h7/oqel of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis. W( (fmd0 bib*fleyn* (bhat is the centripetalb(bfmb( y(**di nfe 0l acceleration?

  How many revolutions per minute must a circular, rotati* : gdvmmi)y 4pms,za6ng space station of radius 1000 m rotate im6:,4)p*avmmy szgd to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m0toj ax.o h*/e radius turn at 96.5 km/h. What is the centripetal force on the motorcycle?0o oe /j.x*ath

  A 0.50-kg mass is attached to the end of a 1.0-m string. The6qs7i00 jv cor system is whirled in a horizontal circular path. If the maximum tension that the string7vc0si6j qo 0r 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 j7e- ytcewenf(w2r z9v(23a ja 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 stone's speed at this wj3ejrt97 v2ec(w(za yn -fe2 point is given by

  A stone, of mass m, is attached to a strong string and whirled in b 8vs7pr7q: bpa 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 sto 8qb7 vrpp7:sbne's speed at this point is given by

  A jet plane flying 600 m/s experiences arif3w *qqhm/ )qk9z* mn acceleration of 4g when pulling out of the dive. Wh9m*/*wqr)f qkzq im3hat is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outsiuee5vx kjhs/- ,1-ip8*r ocdtde vertical loop (in which the center of the loop is beneath hio /tjc d *x85ese1hu rkp-v-,im) 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 stand is about seven times ,yica g2(4 zkmr -c0kcr7i;gk his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can2yzmrcki7i( 4 ,;ck rakgcg-0 tolerate at a speed of 250 m/s?

  A car traveling 20 m/s roundsb+539l; v)e6zwl tx.oonlal e an 80-m radius horizontal curve with the tires on the verge of slia n)l; lexo +l3w 569.evbolztpping. 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 surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. k1c q(z)jchn ;The centripetal force provided by fr z;n)cj1 cqh(kiction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve bi08z t vs77lcof radius 50 m at a speed of 14 m/s. What must be the minimum coefficient 8zb0sl tv7ic7of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant 1 n6n5 lhwvl;h t*b7gvs/)vqt ;)mkwy speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum rad)lghk/1l 7wbw5s)t;nt yvhv6;v qmn * ius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negotiate a2m9,22o ,hkvu(d5 qppv 1 m hiegra(bs 100-m radius turn at 35 m/s without skidding? (Ignore frictiok rghepi95122p(oq dm b2av,s, (mu vhn.)

  A horizontal curve on a bobsled run is banked atvof k k:1+*;k,thp aqx 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 100q p9czim18 5ru jlr)2o egb1v/ m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i-7s bjjh+hts* s 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 endbt(x+ym9q 6ue of a string is revolving uniformly in a horizontal circle of radius 0.500 (eyx6u btq m9+
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 carnwmji5 5:f4,cz) i2:5vc x mdvrge+ga accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track vf,mvmn4x cajg) ie+z 55wr gic2d5:: 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 of a protob q4n1dnz 4 9r7/k7aebokac1sn 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 the Earth, due9m2 vm;*jweu:dko8cf to tkewjv:o2f*um9 8mc d;he 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;.loqckjiy1k;/8kmc h: 6o dd. If the masses are moved to half of their initial distance, whdk/o mio;c8kk61lhyj d:;c.qat is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distxruw yst65bl1 z0-)2xzw:lo sljp p9ol2.:tc ance from the Earth will the gravitational forces due to the Sun and the lru1 p2cjwl-o9)st zp.l sby:6: lx20ox5t wz 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 r0tgsh 9 o*rg(is $7.4 \times 10^{22} \; kg$ 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 distad3 nstlp oz*/pswr ).0nce above the Earth equal to the radius of the Earth. What is her accelerat * os3w.r)0/npdpz sltion due to gravity?

  The radius of the Earth is 3f*ti-xau vvf3 3rfo- R. At what distance above the Earth's surface will the acceleration 33vxft 3f avurf-oi-*of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfvy ;/gmln s92n; qbo7bace equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is y;m 2vn;s/9q7lgb nob

  At a distance of 14000 km from some planet's center, the acceleration na+2e 03q s4cit m6zlnof gravity is 4am2 tcil0ezn+n 36sq $32 \; m/s^2$. 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 Earth. The Earth has 8q9lab0 5 extbradius r. If the object is raised to a heib50 tq9 lxeab8ght of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person ch qb +dsh 5rf:.182az4paco wiaange when he goes from sea level to an alt5dz4pr2 a 8aacf1+.hw:ob qisitude 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 point 3r above twp4lt /ruxp /*w2 h+er)x3sswhe Earth's surface. What is the satellite's weigh/xrxpp3 ssut+e wl/h4*r w2w) t?

  A spherically symmetric planet has four times the Earth's mass and twicptqi(sva7rwi *lnl;:-n3 ;r be its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this pt(*;irl sn;iarwq l7 nb3v-p :lanet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the sawer)*wzi h6cu7feqhy k7t)2.me line, with the Earth between the Moon and the Sun. The Moon has a7 w kz6e *7ci.hhwrteyf2u))q 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 is transported to t r; 503warapc;sip qn1he 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* gy9utef; jh2., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of thy*t;f jhu2e9ge Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit sk7 q*;4w;* tqk .:sweanjjgwabout the Earth (i.e., it just skims the surface of the Earth). How l j4gsknjq:w7w kws*q ae.*;;tong 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.5,fh4 33 suugq0uwyd(b e s(ni It is obse4d n5e3(, bqfss 0i hy(uu3wgurved to have a period of 89 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, has an orbg uznrcdqg(4ws)n9p+j w, j9 w jm4t;1ital 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 with5 bvap9+dpi.m 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 c.vx;u 1qfw0porbital 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 ac uq;fwvxp.10n orbit?

  The planet Jupiter is 7 t5k4q.bxcaf $7.78 \times 10^{11} \; m$ 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. What is the o4 b;xnqnu7kw*ko*om 9 egy9* average distance from Jupiter to the Sun? (The distance from the Earth to th9q*k myxek**n ;gbono4u9w o 7e Sun is $1.5 \times 10^{11} \; m$.)