Is it possible for an object moving with a constant speed to accelerate? /z4lhh x3:cedtc3 i1eExplai/3h4:ct e3cihdzx e1 ln.

  Consider a particle moving with constant speed such t*ujx+zm a,i:2,raoahhat its acceleration of constant magnitude is always perpendicular to ita*muo+hi2 ,rajzx ,: as velocity.

  An object moves in a circular path at a constant sy..7vykeziow8 9/m(*/ isp /gzrr zis peed. Compare the direction of the ob(ks*m.ogpr zi.y/v / 9ewr 8zz/i ys7iject's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction o oslobv gz1th5 )(y5gjil9a+0f the acceleration i l1zh 5)ot0yb(sagjg lio5+ 9vs

  Consider a particle moving with constant speed such that itfcv n 9/,+o9hwlac c,ts acceleration of constant magnitude is alwaysc /tc9 nvwalo,c+,9 hf perpendicular to its velocity.

  What type of acceleration k.*nwpo) 1 rbmdoes an object moving with constant speed in a circular pathm )ko1r. pnbw* experience?

  What force is needed to m. 3n(vpjwjeu ugc+c4 0xc2e f.ake an object move in a circle?

  When an object experiences uniform circular motion, the direc9:qk 1 p nlny;: dwoj/1ooe8vdtion of the net force iydoe/op l1dv owq:k:;j81 9nns

  A roller coaster car is on a track that forms a circular loop in thugn1y56w9+eb 6l mk;arz ug5g e vertical plane. If the car is to just maintain contact w nl9ug5ew6y5 zbg+1a;mk6gr uith 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 a circular loopdw t/bs b+60al (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of thtwsbb0 +dl/a6e 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 imy/). kzsz/4ixvy yc-s going straight up. Just as the plane is at its lowest poyz vi kc x-/4/yz).ysmint, 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 ck5wm u y :(ibupe3v1oig/2 kc0 j-st+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 speed v. Then i*qa0mclico /jqo79a2vp73b o ax.p t9t goes around the same curve at half of tob 2mx*3/ t9plpa0 qo.o7aq iccva9 7jhe 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 t7t d,xrb+-ik7ypz(v at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, t7d+pikx7,r v bty-(zcompared to the first?

  A car of mass m goes around a banked curve of radius r with sp8p2 dthf(m+32eoin tdeed v. If the road is frictionless due to ice, the car cand8mft+ i32doehp t(2 n 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 are banked at t33ooitu v 1ddq)d v4a,he same angle, but one has twice the radiusdo3 ,u) qovav4d1it3d 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 On59mzt a-de;s lympic bobsled track is not constant, but increases upwa;azs -n et9dm5rd 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 . -b ;n qgqfr. xyhbr.v2s42ipky8,lgmoving around a circular path to have both centripetal and tangential acceleration glx ;yrgi p2q2.k ..8,bsnv-hybr4qf?

  The gravitational force between two objects is prope.k 98)r1a+ wbn/uaeyi4myvjf+2o b r ortional to

  The gravitational force between two objects is ie0 +h(ea xxs;qnversely proportional to

  Two objects attract each other gravitationally. If the distance between tpqwer :(:ls, their cent:,(e p:wtlsqr ers is cut in half, the gravitational force

  Two objects, with mass esey+ 9(wf4h:.kjmfp+ w5t qxes $m_{1}$ 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 mass 1c+0z6ef*crvp5cu21lr xw hqes $m_{1}$ 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 ).pf9 o5in ;jznqu3ea universal gravitation.

  Compared to its mass on the Earth, the mass of an object onafqb nw3w . n;:r-m)qj jbwb,; the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. 2 fa9kmtbtmtci -r+9+ 87nfsnAn object of mt9t789ankmn f-tb+2cs+ imrf ass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surfg-2gvwyjyz(v7 s i0r :ace, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it boc/ggo (jj z uxgdc-9i7 v2.x8eyond the pull of Earth's grc c .-oxd g 9v/i2g87x(zogujjavity?

  Suppose a satellite were orbiting the Earth just above the surface. What is t;,)9y ea8bdh rsvvw 5its cent8vh ea,d9bvr5w;)ytsripetal acceleration?

  A hypothetical planet hasg2 m m/nluiffwap2* *3 a mass of half that of the Earth and a radius of twice that of the Earth. f2iw/ ug3f2*amnl *pmWhat 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 one-sixth what it is uz/ha:2a9m8i (cdccbon Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass co9/bu:cm 8h(dcz2 ac iampared to the Earth's?

  Two planets have the same surface gravity, but plan mqxc8h :l8a+,j/mtgo et B has twice the radius of plane 8l,a+8jht/m om:xcg qt A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same571ez hn8v bgw surface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of planet vb158wne7h g zB?

  Consider a small satellite moving in a cc3en4g p01 *t ev0noidircular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital pt1ce *v003gin 4eondvelocity?

  Satellite A has twice the mass of satellite B, and rotate1 9q12 ojw4uf+qj)up9dnv owes in the same orbit. Comp ) oenq puw9+1j4o92duqvfwj1 are the two satellite's speeds.

  A person is standinguef i4v-zj pc2xo/)h : on a scale in an elevator accelerating downward. Compare the reading on the sujzpcx4h2) ve if/ :-ocale to the person's true weight.

  Who was the first persamj7 ,l nvq7l w04ncn7on to realize that the planets move in elliptical paths around thn a77q,v7m lwjn0c l4ne Sun?

  The speed of Halley's Comet, while0egc stc--.sw,53 .nryeg bw q traveling in its elliptical orbit around the Sgwysnw.see., b-rqg- 3 ct c50un,

  Let the average orbital radius of a plane iw/x0,tx;uxgt be R. Let the orbital period be T. What quantity is constant for al0; xxuw xtg,/il planets orbiting the Sun?

  A planet is discovered to orbit around a star in the g5zt yc3,r*ajd* yve3e alaxy 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 tj*35veteyr z*ayc, 3 dhe period of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from thg.qt8lwz:j4gb19 s t ne Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun:jzgws 8q9 ltb. 1gn4t in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.sju b;u:-t( t0c)vf: cv,xflv

  List the four fundamental force6 61l wb1zojves in nature.

  An object moves with a constant speed of 30 m/s bx2a n(l j yhpycr(8nom; -k00on a circular track of radius 150 m. Whatph0xklj08(b-an ymn2oyr ;(c is the acceleration of the object?

  The maximum speed around a leve6enb8*.ssdu7rl 8.u al :jkt yl.as (gl curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Ass 86 t . ar7b:.la.lg8ssydkesu l(jnu*ume all other factors remain unchanged.)

  What is the centripetal acceleration of a point oc mcbicuu4 1h/342azmw -k7xen the perimeter of a bicycle wheel of diameter 70 c3h2i7ce1-c cz x/m 4bkwu ua4mm when the bike is moving 8.0 m/s?

  A point on a wheel rotat h;l3 annxpr-99hi ;bping at 5.00 rev/s is located 0.200 m from the axis. What is the cx9h-pnh9p3;bla n i r;entripetal acceleration?

  How many revolutions per minute must a circular, rozu 3wp 7eh7qxw02.xzxtating space station of radius 1000 m rotate to produce an artificial gravix0 e7xq3uxhw2p 7. zwzty of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at rrl)3t5mv oxss *ims 0my.r2:96.5 km/h. What is the cen ss o*0l s53:riv.2xrm) rmymttripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system ir6 ddm8 +x6zfrs whirled in a horizontal circular path. If the maximum tension that 6rx+86fdmr dzthe 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 vertical c w (*x- sckc3d-n6qsim:pwrd6 .p,fda ircle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weig6s*(-dq.,w: pcrf3cwn d6xdm- ka s piht. 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 circ b) zpfv8r29njf3iz:cle of radcfz23: bj i)zrn9p8f vius 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 by

  A jet plane flying 600 m/s experiences an bi.t/i -xcso9 o- 2dpt;kl p:i (yl2ogacceleration of 4g when pulling out of the dive. What is the radius of-. o 2k;gcx9-ioibpidl t2/yt o:l(ps curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loopqwsc4k - x0 1kqi;nur8 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 8wc s0kn;1 iqq -r4ukxfast is he going?

  The maximum force a pilot can stand is about sevej6qy :4 l8chssn times his weight. What is the minimum radius of curvature that a jet pl4:ysq6lj8c hs ane'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 horizontal curve with the t+m0muf2at 3kt ires on the verge of slipping. How fast can this car mm uf 203at+tkround 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 c/fokp )) f8a7mz9iegflat curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by fricki8m7 )a /ogp9fzf)ection 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 speejkhz4 .paddsqv + 17l )fy-k.ld of 14 m/s. What must be the minimum coefficient of friction between the tires and the road fps1k4lyd..qj-fd k lvz+)a h7or the car to make the turn?

  A car is moving with a constant speed v around a level tq858a/ sk uuiai q2g2wwy/-jcurve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if thaqw8u8/q2 t2i5-suagw jy/i ke car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsl1x tcviu8y*b 6ed to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore ft yc i8vx*61ubriction.)

  A horizontal curve on a bobsled run is banked a;e4nq fgcz5c31+b iu 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 at an angle olg-v8; vw)to /qi+z duf $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankedmfh eegoo147 w8xo2plnk*xf6d8 - mw . 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 revolvirf+ua6wu -c.wfi,r3zng uniformly in a horizontal circle of radius .r3f wuu-c6wz,ar f+i0.500
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 th t0(yk.):lawl 9re(rxk90l makccp5 ge pit area, a race car accelerates at a uniform rate to g9rkkx c:l(a09tekp.mr)w0lc (a 5lya 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)
(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 fx4jcq(m7n(-2nb1w i e b0hwk8wd:i k 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 ; 9dyloz1c sempywk(5 ct e5+8force on a 70-kg person standing on the Earth, due to t de(po5s + ct1lec5z;8k9wyymhe 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 attractiv .kx+ji6rjye3 u a;w,re force between two masses is F. If the masses are moved to half of u+.xyi ,3rkjwer;6 aj their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Ea6fvav:e hlu w,ii61p5rth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun e ,:fa1w65phviiv lu6and 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 i,hy sa5gvt)1x2*, y j )lxeoqds $7.4 \times 10^{22} \; kg$ 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" a 1 jrz.gkr2tt:jn4xa.t a distance above the Earth equal to the radius of the Earth. What is her accelerj:tn 1 r.tjz.r2ga4xkation due to gravity?

  The radius of the Earth is c5w1l: o:ja i3wetyyor68 7iwR. At what distance above the Earth's surface will the accelerattw o:7 1j5y rw:6yl38eicoaiwion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface eq; pdc,jt5 5qnd 5xvon8ual to 3 times the radius of Mars. The acceleration of gravity of thpnx5 5qtv ndc;,8jd5oe satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 t l+veule69;f3n3 mx eje90ejkm from some planet's center, the acceleration of gravity n vj+ee;jxee90m 3 63ule tfl9is $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the sa br84 vgqx c.*k z tnm28,fwjyfk) b1xm(ek;.urface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surfacw* .maxy)mfk1(cb.g; 8qt2j x,v8zebkr4knfe, what is its weight?

  By how many newtons does the weig7w k2 i :skqgjtnr0f.s0 bdeu9 (4b7sght of a 100-kg person change when he goes from sea level0g:bbgd s974k ws (erunki 7qt 02j.fs 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 mass 100 kg is at a pointds . qjh3h7rzn72j6pu 3r above the Earth's surface. Whats3rqp uj6jn2z7 d.hh 7 is the satellite's weight?

  A spherically symmetric planet has four times the Eaz+vl k,.7n *iwb kn*dydl0h o1rth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how muh*od liw+znynbk 1*l,d7. k0vch would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the samuq)xl3gf3 )qhu ij7g3*fuw -s e line, with the Earth betwfqh3s fuui*w3-)uxq7gl 3j)g een the Moon 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 is transported to thes58/t y0plww j6yac s9 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 wl7 jd k.dfzm+mg):o s5gber ;k-9cg)just skims the surface of the Earth). What is the speed of thlmmbk; rd)9: +go5 ) -cg wkzjgfdes.7e satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low zehm,y-ee8 q- circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long demze8qyhe--, oes 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 orbiqg+ kxdl1vn5y ,kkos*e08 jg8t 230 km above the surface of the Earth. It is observed to have a period of 89 min. What isv81gn5qj +lg ,xdk*oey8s0kk the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupite8ocwp5z ya /yy+oc m7sip./8 kr, has an 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 Jupiter orbits the planet with a radius of/, q;kmdx lnnnp3*jxn.zw, wu11 j4bf $422 \times 10^{3} \; km$ 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 orbital upizq 2/ynn 15h 44o:ppfac/ qradius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How lhpcn 4fy/zn2p ua15oiq 4: /pqong does it take moon B to complete an orbit?

  The planet Jupiter is ow n(u 7 o//chzejqyfq 6/m*jfse*c22 $7.78 \times 10^{11} \; m$ 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. Whaj964o jpm+h3, ibx 4euc(14sbqjn iijt is the average distance from Jupiter to the Sun? (The distance from b(x494ii 6 3jn,uioq+4s1hj bejmp cjthe Earth to the Sun is $1.5 \times 10^{11} \; m$.)