Is it possible for an object moving with a constant spelr7tr2, t8 vqkk egy67ed to accelerate? Explaint68vk7ek trqr,l2 y7 g.

  Consider a particle moving with constant speed such t ,gr th)mkmu3vjmmn2+ iwnf a*+r 4s93hat its acceleration of constant magnitude it,)2+ r3+imnm amuwf4n k m9s gj*3rvhs always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Com/pqmz34v o 5ogpare the direction of the object's velocity and acceleration vecgozp5 v4m 3o/qtors.

  When an object experiences uniform circular motion, the direction ofalrh*qa2- wn 0 the accelea h*r0l 2nqwa-ration is

  Consider a particle moving with constant speed such that its accelevhk4fz99z 83 uf pb;p jav-f8uqqhj3; ration of consk-hp zhjuv48 893 f9pfqqj fbua;vz; 3tant magnitude is always perpendicular to its velocity.

  What type of acceleration doeyp o2bkfkf+63igelx 49f 18vk (vd-wps an object moving with constant speed in a circular path experienw1f4kplxyvf b38kod-kg2e 6+ fiv9p (ce?

  What force is needed to make an object movxbilzx2*e x dk3 *ch e-x;jp-;e in a circle?

  When an object experiences uniform circular motion,k l,p/fn7d 1myjxd*i/ the direction of the net force n*dx y7pif,md1jl/ k/is

  A roller coaster car is on a track that forms a circular loop in the vertimzd rrto7brqo7r)-* d 8sx9u/cal plane. If the car is to just maintairsod)7u/ qm r8zrob*t-97x drn contact 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 tlki6 e4k0cvn 5rack that forms a circular loop (radius = r) in the vertical plane. If the car i i5 vkkec460nls 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 follows a semi-circular arc until it is gye4rx 0 izt-fe0oh 1zq/+9v vooing straight up. Just as the /xo1fhvvt4z9o 0qez ie+y r0-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 curve 7/dyzq.gc5iks (gd boy l-, y4of 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-j/yjchz 5r :nd v. Then it goes around 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 sy: n cjr/-h5zjecond time, compared to the first time?

  A car goes around a curve of radius r at a consta o5*xiar5 oh*ynt speed v. Then it goes around a curve of radius 2r at speed rai xoo* *y55h2v. What is the centripetal 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 with speed v. w yo4 b--fxys..l-lxekc 7k0v If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component ovwyoxc7.. e--x l kyk-4l0bfsf the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked a0./3 j/osquo-pjiz+ aswt )a jt the same angle, but one has twice the radius of the other. The safe spee. qso i3t)jjazuopas /w 0/-+jd (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 not constant, but q3rxj-lm fx 2n)(+x seincreases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "+ xxe-f3mj(2rn) qlxsclimb 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 bo/jnf;j xgh )a:th centripetal and tangential a/:h j fxjagn;)cceleration?

  The gravitational force betwee, pib)mij2gt,t 8zak 2n two objects is proportional to

  The gravitational force between ti9zwp.:q ,oz4 k oaz7jwo objects is inversely proportional to

  Two objects attract each other gravitationally. If the distance 3ktp92vr pe etiu;c6pac ;69bbetween their centers is cut in half, the gravitatc k cpr;9t6ape2tei9b3 v;u6pional force

  Two objects, with masses x1q+2 dcquo3l$m_{1}$ 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 ma6m4ep9iy +-5*dg pwgrtoub r* sses $m_{1}$ 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 gravitatio;bo9qnv6-kzb wl 2+f, hjt2e fn.

  Compared to its mass on the Eart 1w5b hxkb++8d,/skydce-de m h, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An owiaky4fb 0cx -o, .al6bject l0 .a4-ycf koa6wbxi,of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth'jm t) dx (by.(e+eng+ps surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point i: m n2)b)q1qm6rxavhta; 1yqs s it beyond the pull of Earth's grav qv1x1thm ;qq2r6:) snyam )abity?

  Suppose a satellite were orbiting the Earth just above the surfa n.7 esqu7j9/ufm j(ty*6wibu ce. What is its centripetal acc7 /w7t9iby(jmjue un*f 6. quseleration?

  A hypothetical planefzrt((t 0:+ql2uekz) en rzj6t has a mass of half that of the Earth and a radius of twice t kl2ze60 rn: jzz(t( tq+u)efrhat of the Earth. 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 Moonkad 3ula1su t(so 5bhw a;9+o d:y2zo* is one-sixth what it is on Earth. The radius of the M2u1t 9uy(sslobkaad;ao z dwh *+35 o:oon is 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 twice the radius ofy-khrsxo 8bjv-: kl(. px8.l vor -h-s :yk(jbklanet A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B 0gg5p.gqqh u:has twice the mass of planet A. If planet A has radius r, what is the radh.g: u5qgg pq0ius of planet B?

  Consider a small sateltr/k hhgem3) 2lite moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this sh )g/hrtk32meatellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in thet2qdqv mo8,m.c 9h*cpnao7mg9c 2hk; same orbit. Compare the two sat2copc2m,qg7.v89 cmmhno*a qthd k ;9ellite's speeds.

  A person is standing on a scaleq2al2b,-/+mzjnesecbn8k 1s in an elevator accelerating downward. Compare thbaeb1n slen/c qj2k s-8+m,z2e reading on the scale to the person's true weight.

  Who was the first person to realize that the planyw;wqak 40p/d l 2/gjkets move in elliptical paths around the Suwk/0wdkp/;ajq 4 yl2 gn?

  The speed of Halley's Ciw bf3j*.l1 5cfncs faxcby784g+9 wwomet, while traveling in its elliptical orbit around the Sun, 5bjcs1x4 n9+cacwg.7b3ff fw*lw8iy

  Let the average orbital radius of a planet be R. Let the orw. o )c fldu,*wa/7nmgbital period be T. What qm .odw,n 7cua*l )gwf/uantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a s ;jfh26df+kxe1x;-nkdrqy h-tar 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 that6j; 1nx-k+x2eh ; y- kddrhqff new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as one "fmg a:)q g)2wxastronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the aster2)wg)m qx:gafoid's average distance from the Sun?

State Kepler's laws.d xtu4pbtv2.o5g. q5a

  List the four fundamenn+vyq l20we8edyvp.m :mq/ 6rtal forces in nature.

  An object moves with a constant spesjx-u.r n2;jthn,iu 9ed of 30 m/s on a circular track of radius 150 m. What is th-ut.rh nsj 2nuj,9;ixe acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. n 25f9yu3i c 7k9jyn3.egp oef What is the maximum speed around a curve with twice the radius? (Assume all other factors 9y59nff peku3 e gi2jyon3 .7cremain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle 0eyr,b, 2 kywgwheel of diameter 70 cm when the bike is moving 2,,kwyy0reg b8.0 m/s?

  A point on a wheel rotating am c8 nwx):g (ftcjdh)(1fx de5t 5.00 rev/s is located 0.200 m from the axis. What is the centripetal accelerat mdf()h x f58e ()1jcnxct:gdwion?

  How many revolutions per minute must a circup1 .8gbfaszt,wu;5j- /szthwlar, rotating space station of radius 1000 m rotate to prod s/bwup1 t- 8h5wzaj.;zst,g fuce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m rad2 m 5aciej n0nx+c7v:v l(q;reius turn at 96.5 km/h. What is the centrivl(xn jnmc7er: v;0q ciae 5+2petal force on the motorcycle?

  A 0.50-kg mass is att87xgn0yrvvsdq*mtzn(gk+vk5 5f7 * a ached to the end of a 1.0-m string. The system is whirled in a horizontal civv*+*tax5rgf k75 0ds 78kmnyzv (nqgrcular path. If the maximum tension that the string 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 a strong string and whirled in a vertbt2i lqb(r. 9 5ja0pldical circle of radius r. At the exact top of the path the tension in the string is 3 timb9plalbi 2( jtr0q5 d.es the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in a vertical cnobl k p2/.e)9zhh/ ovk4+ p5vntt:ydircle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The skvzv/.p pd kb/o o9n:)eh+nt5y2 hlt 4tone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when pulling ouov zej0ulr7mc,c:/- xt of the ccom:elr7/j ,-x zv0 udive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which thcw5 r9,xidnh4rc u-: mk:k jt4e 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-half of his normanh9k4cidt kr :uwr :x- 5c4,mjl weight. How fast is he going?

  The maximum force a pilot can stand i5ukl,)ifm r4- ,k jdvwra a4.es about seven times his weight. What is the minimum radius of curvature that a jet plane' .u) 4k,,vewd-jmlf 5ia4rraks 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 horizontal curdor les5w,7 00wucdo+ve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same c7,o0ew0oc l+ du5drswoefficient 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. z1;bwvq r6m;h The centripetalvqm b6;zhw r1; force provided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat -q(b cn* (d1 y /+ruyhzlzjco3curve of radius 50 m 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 make the 3r-/qd znj1z buch+ c(y*(oylturn?

  A car is moving with a . rmb mbenk;35constant speed v around a level curve. The coefficient of friction between the tires and the be n;.mk bm5r3road is 0.40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled krnybdu57v6xg 4bir 8 ,wxuap(.;g6b to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fri 8 ;ag ,vw6xrn(.75gridu64xybbb ukpction.)

  A horizontal curve on a bobsled run is banked athk :.0gl-wz (,ivnzj l(tpru4 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, i j2t6q2nl,x 4f4 sxxobanked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankb tupq+* h ,i/ab9c9 smen7bahug) j1 9k3h5gked 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 aw .6 xvzy;zm6end of a string is revolving uniformly in a horizontal circl vm;yazx6.6z we 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, uu/z:9z 1n *2msks2o nzo8h t-yxmf: pa 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 blau/2mzm :1s nn*hk 2-zspy: to zux9o8fnks)
(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 3 5cdtlvl slh9:kl+)qmass $1.67 \times 10^{-27} \; kg$ 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 standi*eqs07q/2p h tmkskh( c 1g2bhng on the Earth, due to t1khh qgq2me /b0h* s7(p2skcthe 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. If the masseq7hkgln ;7f 5ubc.w 6cfff uh/cbwu713ncy8 ,s are moved to half of their initial distance, what is the gravitational attrlc65h ,qf7y;3b w77wf1fnkcnuf u 8bh/cg c.uactive force?

  For a spacecraft going from the Earth towardm:--stb3f 7a mfk/ rxa the Sun, at what distance from the Earthfmk7xf--ara 3/tsb :m will the gravitational 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 y5yv /nv nu wj69wnisv:;j. o.fyi25q$7.4 \times 10^{22} \; kg$ 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 equal to 1b9nw nae o r p7x*gr25b1gb2x1qc6hqthe radius 1enx2bcq b9612a gwb nx5o* r7q1pgrh of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above theaqj(xb igr4 *k r19i3e Earth's surface will the acceleration of gravity 4xg r(ik ebia13r*j9qbe $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal bvjwf+x)z yj74ej*hp yhf u) hc0nk2w4y9) (dto 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the accelyf)uywwfn(j9)v ph zcybjxh+72k4*0 j)4ehderation of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's centlsbb*t/ k* qk.9i j-fyer, the acceleration of gravity is /tj l-b.b9*sykfk iq *$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N oa6t( jh;ooz o2n the surface of the Earth. The Earth has radius r. If the object is raia; h(6jtzoo 2osed to a height 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 goooi7y q5o15ms es from sea level to an a71 omyiqo5o s5ltitude 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 6g7n28 i w;qm dvxj(ufi*cnm5at a point 3r above the Ear6uci7d (wjx5f 8vmmn2g*n;iq th's surface. What is the satellite's weight?

  A spherically symmetrii0zkv).qs aa7sfho1 na5-r (qc planet has four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the suo fsa.va 5qh)n(1 asq-kr7z0 irface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Eaw hw1c a,hi2u8rth, and Sun all lie on the same line, with the Earth between the Moon,cai12hu w hw8 and the Sun. The Moon 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 ball efd6 *rqos1 k5is 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 just skims the t1n)/ hm8 zcouvgenful-(j3m02i8ik surface of the Earth). What is the speed of the satellite? (The mean rajl2z)nti c(kuv8 /-8g fnmeo01him u3dius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low chsy w;u4l;rqa(41gy/abt( r wircular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to4 /1blg(a ;srawu4 hryy; qwt( 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 surf429+7ro6kozv ajbb d race of the Earth. It is observed to have a period zvdo6b+9o ka4brjr 72of 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 orbital vaa146hku1um j5;j cddiameter 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 orbipdr y1:. mic3vts 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 lx/y ;awn) z2/c yctnsoas) 47circular 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 dz aal;c/sy s72tnow)4c/ ynx )oes it take moon B to complete an orbit?

  The planet Jupiter iscu ;df65.0dy lwadvg6 $7.78 \times 10^{11} \; m$ 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 Sunn+ci )3htvi7 q2hksg3 ux a/1y once. What is the average distance from Jupiter to the Sun? (The distance f+qh2gca 13i husnyt/vx3 )k7i rom the Earth to the Sun is $1.5 \times 10^{11} \; m$.)