Is it possible for an object moving with a const;m3fj7gc2 9fmfoc niwb( p47ewf6e)y ant speed to accelerate? Explai w63 f(mebf4w 9f7ye7m nc;f ic)gp2jon.

  Consider a particle moving with constant speed ct/cz ,)2 h59ffwv orfatdv:+such that its acceleration of constan)t+ :h ffvfcarz2wv t5 oc/d,9t magnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant spetc,6zzbmr0 zj sdj;)1 ed. Compare the direction of the object's velocity and acceleraticrzj,s z 10mt6; dzb)jon vectors.

  When an object experiences uniy p/57bai4by6e)qsq nform circular motion, the direction of the accelera qa4 ip)q6bs/5bn 7eyytion is

  Consider a particle moving with constant spee8m*kmr (d pmplm-7uj( d such that its acceleration of constant magnitude is always perpekpm(mmm( p -*jr l78udndicular to its velocity.

  What type of acceleration does an object moving wig-ort-qwz +a/th constant speed in a circular par /wo qg+-tz-ath experience?

  What force is needed to make 4m 5 k5ujoizl*an object move in a circle?

  When an object experiep 4n x itequ;2ic,bhiq ((8o3 nflet*6nces uniform circular motion, the direction of the net forc3nc u 84ipqn2x( tlq,(botfiei;6e h *e is

  A roller coaster car is on a track that forms a circular loop in the e9eto6e9c+ e vvertical 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 evete+c6 9oe 9point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (rad guk4g+6ljl )cqy rdz-g mv4*2 w,afn+ius = 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 poin-4 4+qu+wvzjg l6mrn*yakdfg2,)l cg t?

  A pilot executes a vertical dive then follows a semi-circular arc until it issv ,1bd-zuva5 going straight up. Just as the plane is at its lowest poid su v5zavb,-1nt, 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 radius8v ,yj2wb ( hs:qogej2 $r$ 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;adprp9q q.p/uv + a8w6a4wadt speed v. Then it goes around the same c+w9 avdp;u /8pdpqq a4 .waa6rurve 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. k-ma,o5vep5yq7rw6d 3h oxg03b c)og Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the cah v 73mebrd cxwqygo0ga o -po5k3,)65r as it goes around the second curve, compared to the first?

  A car of mass m goes ar4seprm uf ja6g.w g5--ound a banked curve of radius r with speed v. If the road is friction mpaer4-f65g sguwj-.less 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 *4jxvk)b y,xz c77i* ile3 adkare banked at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for t c47,aiix 3jby*xzd7lkk )e*v he 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 not cons4/zoum,f7li+gt ;dlz tant, but incremgolz/,idf4zt7l ;u+ ases 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?

  Is it possible for an object moving around a circular path to ha ..0 gta2 vf0fbin9tvgve both centripetal and tangential accele9 fg.n.tig a00t fbv2vration?

  The gravitational force between two objects is propo2mg ounc+ s* ))huc7wjrtional to

  The gravitational force between two objects is inversely proportional wpae z y7k*9g2 w0en5nto

  Two objects attract each other gravitationally. If the distanceg *5stt4 xc0epgea7hb8w3+ s1* laekw between their centers is cut in half, the gravitational forc hxl0e*1t4ecg p tse+kg75awb3a8 sw*e

  Two objects, with massesnkb6 imw:l rt.(sfr qk -qc.99 $m_{1}$ 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 massio+on3kcy; 8s+ 8pzvxes $m_{1}$ 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 gravitat-z/maqk9( k9 v/qiugo ion.

  Compared to its mass on the Earth, the mass of an object . n, wupo;g6ohvv/fmpz k-3d(on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. 5 0bkj1l4vfac An object of m0cv5k1 abjlf4 ass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rockx(xu c;kg ;)pyet's weight

  A spaceship is traveling to the Moon. dgphw0evgjh385j qkm 500x7q At what point is it beyond the pull of Earth's grak5j3 eq0xhwm5j7 d qpggh00 v8vity?

  Suppose a satellite were orbiting the Earth just aowau0 z :8jp8xbove the surface. What is its centripetaljozu8 xp08a:w acceleration?

  A hypothetical planet has a mass of half that of th3dd2evk.nqh q,ch h1(*d prj) e Earth and a radius of twice that of the Earth. What is the acceleration dqpk) jq3 *hd.2h,v ed(ch1rndue 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 one-sixth what it kat4 z3 x,dg7jis on Earth. The radius of the Moon is one-fourth that of the Ea7,ztk3g4 d xajrth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surfa50j7jpb9m 09ltlps rmr+1dnk ce gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass opm9r j7d51 9rnkb0+ mjp0tls lf planet B?

  Two planets have the same barni*cy,/k- surface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of,kr* c/i-ay bn planet B?

  Consider a small satellite moving i8, qmdg;w*n4+nre whwyf jo(( n a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's oo *r+m,4we; hwnngy w dj8qf((rbital velocity?

  Satellite A has twice th ;yy(jc bbjbw 2w .7fvuz,- cfg/9fke2e mass of satellite B, and rotates in the same orbit. Compare the two satellite's spee9wybwbuvy,; cf(j k.e7-2bj fc/fg z2ds.

  A person is standing on a scale in ,1x( 2x5mjezzg *fgzg an elevator accelerating downward. Compare the z(zmf,eg ggj25z1 *xxreading on the scale to the person's true weight.

  Who was the first person to realize that the planets move in elliop0*azq lu th*,gf; ka20 6wusptical paths around the *ukhgw0,qlu a6f0p;o*asz2t Sun?

  The speed of Halley's Comet, while travd0fro )uvak, qb-+orm8y/cqus6l m +;eling in its elliptical orbit around the Sqcm+o-yuod) 6 0m8vrfs, + ual/bq k;run,

  Let the average orbital radius of a planet be up).ljpa;9 ccR. Let the orbital period be T. What quantity is conlju ap 9.;pcc)stant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, with themw+ 4;u-0 n zpu(t :q6ngzltxbwc3fb) same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of our Sun, whp+zm t4036u;uwn)(lb n-gxtq bzw: fc at will the period of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as oneear+j*+ 6 qm)2pzcnmc "astronomical unz+jen+ m6qp cr m)2ca*it" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.jn0h g260rjticdw 8j7v2)axb

  List the four fundamentagd (l7 7eh(w9vcg ;gzml forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radius 15ic*z9.h 5 g 5ggltm;ld0 m. What is t.lglgz g;im9th*5d 5 che acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum sba6 tpnqi 3b y3k24o5ipeed around a curve with twice the radius? (Assume all othitn33qobpka b y62 i45er factors remain unchanged.)

  What is the centripetal acceleration of a poi7evp 7h/omm3qqb se78 nt on the perimeter of a bicycle wheel of dia7eo q38v77 mh/mqbspemeter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating 5+pzsk-f3 5q oyes;fwat 5.00 rev/s is located 0.200 m from the axis. What is the centripetal acceleration5fs+wf ;e5ok3pq sy-z?

  How many revolutions per minute must a cjp j3/el)g.aaatn kx ti4p5: m0p7 to/ircular, rotating space station of radius 1000 m rotate to prod/i tap7p)m .x lk3jt:4gt5jo p0ea/n auce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m r, owzu55 h:dliadius turn at 96.5 km/h. Wowiu ,z5l5 d:hhat is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end gpz1o12 jq:m d*1pii l-6cqavof a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 35-p dgc1m1* jipzqaoi 1:l6vq20 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 strong string and whirled in a vertical citope0h(3 e8 bhu5 l bk3cp/*tyrcle 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 8k(t3 pu hb3e* th5yl/p0 eocbby

  A stone, of mass m, is attached to a strong string and whirled in a vertd btz ta3l5q. 5dm;ik.ical circle of radius r. At the exact boi5m ..zdqt tl3ba5 ;dkttom 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 jet plane flying 600 m/s experiences an acceleration of 4g when pr66 f hl)eg,oaulling out of the dive. What is the radius of curvature of the loop in whic6,g l 6o)rhafeh the plane is flying?

  A pilot makes an outside vertical loop (in which the c:h 2ins cp6u)*saaq6center of the loop is beneath him) of radius 3200 m. At the top of his loop he isnushq6:i6ac2 p* )ac s pushing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilo/+.wyxdz4gf rv9rqy 0 t can stand is about seven times his weight. What is the minimum radius of curvature that q .yrz /wxrgyv094f+da jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius h4 p b,xug-8qh;z;ll, 2m1ikd us: ihwtorizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 34 xh:8g;wml1pluu- 2kidz,; tis,b hq20 m? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radiu5ajua7y+4 xp gs 50 m with a speed of 20 m/s. The centripetal force provided by frict jay+ua7p 4gx5ion is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 50 ouhb92x cq+ i,uzj /k8m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to makeh/+ik8 ozjcb xq9,2 uu the turn?

  A car is moving with a constant speed v around a level curve. The v(02 2ju2blfxbma r.ohabqq4,o2c z 8 coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if thbq . o (22r qa2xlvjzu0hbb8oa2mfc,4e car is to stay on the road?

  What minimum banking angle is required for an O osn0d5nhy:,i 3zg+ vxi3,hfjg-u t-nlympic bobsled to negotiate a 100-m radius turn at 35 m/s withi3i5 shngn- g j+y:, t,3x0dnufvzho-out skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 9pl)cajgl8 vc0ml p0) 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, bac6,gp63mxphva8 wd+w 6p2 hzznked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b no)p4b(/)2w;db vj l9qx f-ypsxztb:anked 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 uniforkx;)q4e hnem mfmm a::,l-hg *mly in a horizontal circle of radius 0.500 4gmm; *xqmnk-ehea ) fh,:lm:
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 ar8+sv -it. z/yzjgp.*jwlkrf5ea, a 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 numerical value in the blanks) 5igzyj*8 zsrwkl.vp j . f+-/t
(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 proton of mass n)c9s tbh ,r(m$1.67 \times 10^{-27} \; kg$ 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 sd+7h aiw3i;i 9fvyv,qtanding on the Earth, due to the Moon? The mass of the Moon qi ia,y3w7v9f h+dv;iis $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masses l356q qwm2bqoxwm/ 8g is F. If the masses are moved to half olomxqwgb/386m2 w5qq f their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Eaf; d p r b9)o8rwj7p4cyab:.mprth toward the Sun, at what distance from the Earth will the grav 9 y4a fbpmd pobcw8rrp7;.)j:itational 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 *;qyy,z k2r vc a0m3ygis $7.4 \times 10^{22} \; kg$ 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 :n4mar cormr9u zb h+/9b-o/dthe Earth equal to the radius of t9br+4:h cn dom-zura/m9obr /he Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth'sj hcqhyng)8f+2oaq59w vm+4g surface will the acceler5nw2 +)hmy 8qvc+9oagj g fhq4ation of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distanc 9kp//oi mj(jna a1kf+e above its surface equal to 3 times the radius of Mars. The acceleration/p fmk(/okja9 j1 ia+n 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, the accelera )up tir2so sv:ak75b/tion of gravity is ipuaok s:s/ )v2b7rt5$32 \; m/s^2$. 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 Eopw us(h3ll:a 78 -smqarth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its weighp7lwas-sm:( 3huo8 qlt?

  By how many newtons does the weight of a 10n/- /+hgzhmqzrozz:rw 4 f6vw3 2m3am 0-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius ohm-zh3wq6 av /z:mmog4r3 rn2z f+zw/ f the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass8q z94gqq nqdm4(yy 3k 100 kg is at a point 3r above the Earth's surface. What is the sateqq44kdy zyn qm9g83(q llite's weight?

  A spherically symmetric planet has four times the Earth's m)kkz9r zdrc ntvjb 7k0;)c(p5ass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surf(nzk0rr ) vc pczt59 kb7;d)jkace of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all:;bv -mshf8sl lie on the same line, with the Earth between the Moon and the Sun. The Moon has a ma;bs- lm: fs8hvss 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 transp+ y5 n21icmj)tea2abnorted 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 circulakm;k gvn9 9/q)sx; avyr orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean;v9ak9g ym;sn)qx/vk radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a 7ilf/x-c(ir8gxg3 vj low circular orbit about the Earth (i.e., it just skims the surface of the vfc 8jxlgi(/x7 i-rg3Earth). 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 cis8 fvwy o1kp99rcular orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius opfsy9 w9o1k 8vf the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbitr3-s/7 t xzovjq25jy tal 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 plavs*.n va6g)1z44zernly hn5rg v)3 ie net 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 plabg70z x57jj;z4hso cn9wv5 +)u rauipnet in nearly circular orbits. 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 moonghxjc0io p9u+ n4zz7jrvu)a7;s5 wb 5 B to complete an orbit?

  The planet Jupiter is +fs/g/l7cc cg $7.78 \times 10^{11} \; m$ 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 tofg*njaojz7l/ 3 -qhb1 orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth t- *hzjjbnqlao71f3/go the Sun is $1.5 \times 10^{11} \; m$.)