Is it possible for an object moving with a constant speed to accg n mm/zcl*+w33t qen+d6khy7+q ra ;xelerate? Explainq r7 +g33wqt/ z +6mlc+ydne;anx khm*.

  Consider a particle moving with constant speed such that its acceleration 72im55hk+mp,mmd0 cj08oj/d t.qfsh r(vsd kof constant magnitude is always perpendiculhs87, 0vkm m sm td+5kd5do.0(mic 2jjpf rqh/ar to its velocity.

  An object moves in aq8x+ oc0n(glwr/zmj7epu6 ;h circular path at a constant speed. Compare the direction of the object's velocity and acceleration ve7rh8wlm;xz 0 qpo6g +/uje(cnctors.

  When an object experiences uniform circular motioa5.,6gx g7 /t*dv hwhfk7plqu n, the direction of the acceleration isx/,fq7guhh.6 7 wg*kladtp5v

  Consider a particle moving with constant speed such that q6l :ea r9w2uoits acceleration of constant mag 6 9:qul2weoarnitude is always perpendicular to its velocity.

  What type of acceleration does an objectzkli4ac4zxqlwj a,4cqs5 9bc ,.f /mf mrs/2. moving with constant speed in a circular path experien.j/ q4z.wf4 5f2lsbarczmq,cxkm ,4 /cl9is a ce?

  What force is needed 5 .;g0 ym5fd kxcmtkt*to make an object move in a circle?

  When an object experiences uniform circular mgzp+1fham/ r;y*musmo7 . .pkotion, the direction of the net formr*u.o1z g . mfy/pk;ps7 ha+mce is

  A roller coaster car is on a track that forms a circular loop in the verticalv6l1ql4 9 odi/.s qs8 g5qg;tafs dj1b plane. Ildo91fqg 5ssb6v/8.t a1sjdl4 qqi;gf 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 point?

  A roller coaster car (mass = M) is on a trum :e7oab/xd;3mm;a 2:to fgvack that forms a circular loop (radius = r) in the vertical plane. 7mbx ea/o3mvu:a g ; tod;2mf: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 point?

  A pilot executes a vertical dive then follows a semio5)49y1pv8qa7rokm))hn a 9 u2c2dajfbq bog-circular arc until it is going qa4y o a2 ou2 8o bm5v9fqgjn)ck)p9)ha 1brd7straight up. Just as the 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 curuawtp. kvre4e7x*t, ,u9 -of gve 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 constant speed v. Then it goes av6pi qsce+ 7l;round the same curve at half of the original speed. What is the centripetal force on the car as it goes around the curve for the76ic;slv+pqe second time, compared to the first time?

  A car goes around a curve of radius r at a constant 2 t8; yrt u6t-qeg*messpeed 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, comytu q2gr*s6;- 8etetmpared to the first?

  A car of mass m goes around a banked curvrn s//2by 8vise of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal f/y/r2n8viss b orce on the car from the road is equal in magnitude to

  Two horizontal curves onfrpj v3o 5v ;-4s ifwh4;jntk8 a bobsled run are 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 the smaller radius curve is v. What is the sa;o-wjv 5kh8 4vi ;rfspn4f3jtfe speed on the larger radius curve?

  The banking angle in gp -.3gh1hgfi,ok-jw a turn on the Olympic bobsled track is not constant, but in.-kghh1, fo3wpg-gjicreases 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 alfe06o bt ;/ryround a circular path to have both centripetal and tangb;/r ot6elf0yential acceleration?

  The gravitational force between two objects is proportional to3iur v)op6jtv7n8 v pp:+ h+oy

  The gravitational force between two objects is invj36dew)xcb1 e :w(zgvfc .e. xersely proportional to

  Two objects attract each other gravitationally. If the distr6kwb x*o-l-p ance between their centers is ck-lwr*-6 o xpbut in half, the gravitational force

  Two objects, with masmlleq2z * 9byus/* cq;ses $m_{1}$ 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 *0t+ckrj ji9i$m_{1}$ 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 gk9q* ng7)(t4amo y earravitation.

  Compared to its mass on the Eart:ejr)2z ;s2 tcp wpud8h, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on m6 9xx39qyne t;wq5*ynm2 ka cbcl1m0Earth. An object of x2tx5manql y03q91 ;mb6nkc ce y9mw* mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's w*v, ecdoxx8e 0eight

  A spaceship is traveling to the Moon. A/lajc2- pai5 ft what point is it beyond the pull of Earth's gra /lj f2-cip5aavity?

  Suppose a satellite were orbiting the Earth jus c(gg n,pjeyk;ce7+wv kiz19y8-4wwjt above the surface. What is its centripetal acceleration? w9-8g zkyy1vgwn7je(p+w i;, ck4c ej

  A hypothetical planet has a mxy xc x vl 9,-7qofdjg;icd(o8l9x6c/ass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to8qdxd y x ;g jolxf/iv9,(7co9-6 xccl gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity gcni s-kiq+8tgg2( . pon the Moon is one-sixth what it is on Earth. The radius gi 2+ipcsgt.-8 nq(gk of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface yh85;sjq5c xbz bm x:3w/sbo *gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of planet/sbz xsbo:5*b3h;85yqxjw c m B?

  Two planets have the samo lk .pupt.x*.ix; v8qe surface gravity, but planet B has twice the mass of planet A. If planet A has radq* pi.k .. pxv;x8otulius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit c5yl45,gy yg/fhf d f5(radius r) about a spherical planet y/yffyf5lgg4 ch,55d (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of sateyro gxu+6 0t a3*oatx3+,vkoi llite B, and rotates in the same orbit. Compare the two satellite's speea,o 6oa0t i*t3or+ uy+ 3vxkgxds.

  A person is standing on a scale in an elevator ac0 uh)oi6* jbc0xfm(xscelerating downward. Compare the reading 0icx6 hx0bujo(sm*f)on the scale to the person's true weight.

  Who was the first person to realize that the planets move in elliptical path2) 6lge m8ltqchf 4s+ks arou6lkem8h+)s clq4tf 2g nd the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbitha-pc-czl0j s38/i gh around the Sulsiah/8g-0cph z-j3 cn,

  Let the average orbital radius of a planet be R. Let the m5dwzzs8./ ,wkboxs + orbital period be T. What quantity is constant for all planets orm+ ssz.db8wzkxw,o /5 biting the Sun?

  A planet is discovered to orbit 6wp8w6-m- sxesu 7 fixfi9hz.around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star x- su -mw6 p.wish 7f6eixf98zhas 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 Earth to the Sun is 5.2h/z s +(kcj iyocdnsix;i5defined as one "astronomical unit" (AU). An asteroid orbits ty; k.2i5d( isx o snj+zcc/ih5he Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.a 88bdib o:r3oeb:x3c

  List the four fundamental forces in natubc3teylyys1m l . ,ti/4+ roi-re.

  An object moves with a constant speed of 30 m/s obn +phb)i+ k.b 3fsska0e 6hn6n a circular track of radius 150 m. What is the acceleration of the objec+eh ska0)hsfbki 3n+ b 66b.pnt?

  The maximum speed around a level curve i/ k*jolki ;n3ns 30.0 km/h. What is the maximum speed arojon* kk3lni; /und a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the peri, /e ac0j9 6ueq8iqvodmeter of a bicycle wheel of diameter 70 cm when the bike is moving 8.0 0c,j/q a9 eo6ed8viqu m/s?

  A point on a wheel rotating at 5.00 rev/sy1 t*c/;d- u1 dvdtnio is located 0.200 m from the axis. What is the ce-o*1/nvcudtdt;1i y dntripetal acceleration?

  How many revolutions per minute must a ciw hr/d)fj2hu5* jiki-rcular, rotating space station of radius 1000 m rotate to produce an artificial gravity f )uhk i5hj/j-wd i2r*of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at s:4j zhv 8a9 z: ks/5i.xuxoqyg5w6qc96.5 km/h. What is the centripetal force on the motorcycly q ck z:o su9:5xv/.qg84hs5ija6xzwe?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The syst30kkc1e6 yl icem is whirled 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 y3cci1ke 0kl 6string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a vertical ra.7 jfbyh58 acircle 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 r5jfbh 8y .aa7this point is given by

  A stone, of mass m, is attached to a s*ffukvq h-) 3o5 lhd:xtrong 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's5fu)xh*:qohfl-k v d3 weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when pulling out ol k l kvvhzbq046/.a4zf the d h/.lz4 ak6k0qv4vlbzive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in whr3rf0zrrxcp yc497gc:2jwq-47 sqgqich the 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 on9fpqg 7wx3-2cj4 :rqgcyqz7c4 r r s0re-half of his normal weight. How fast is he going?

  The maximum force a pil8)y2tv*ehmg):b ndbx9q i 8wtl), p zkot can stand is about seven times his weight. What is the minimum radius of curvature that a jet plane' pxv,9dqbyik )m2th8*:n e)w)8tl zgbs 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 tk u(n k/sb1*4g:x ezhco02tw.2 .ckhnqd) j iqires on the verge of slippingxt(uehdg) .kc w snq : *ok0/bkqh 4j.2nicz12. 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 2likb n5yxpe+k1z1+(xo( v weo(2b a5s mkra./0 m/s. The centripetal force provided by fric(2a 15oovkn z/+ekmwe(x xk +(il rs y5.ab1bption is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius umt 0f8m6e7za50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road 0amuemft 67 z8for the car to make the turn?

  A car is moving with a consta.mt. ag r *ty9b)ckg-vnt speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. rggk.t m )t.abv9 c-y*What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required f k .h0*hmajj5g 3-swfjdw4yu1or an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore w0w.*34j d h1jusjmya5g-kfh friction.)

  A horizontal curve on a bobsled runzg+ -rxh 0oeq-a 09 l,aa*dddo is 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 at puk+a1 9lmxi l,f4j ,aan angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked a ojxn7s1qcsn5*je1bv i47/ls t $45^{\circ}$. 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 uniformly in eye;yk7v pu8p *o-oi2 a horizontal circle of r epk7vyo*;i2-u oep8yadius 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 un jux 0/pwleh1i d3p/2giform rate to a speed 0 g u ipw3h2e/xpl1j/dof 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 consr5a icgh3 ;icg27 .pibists 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 *9m-gv2kdg rvdz-fc7 person standing on the Earth, due to the Moon? Thr- m*z ckd2 7v9g-fdgve 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 mapt1 nx+gtm 9yn fqm(m1v8oy2p/(/nmbsses are moved to half of their initial distance, whaq m1t8ny/v(fytn9ppmmn/ o 1 ( g+xb2mt is the gravitational attractive force?

  For a spacecraft going from tfd wq-ffo. frlp( ,0s5he Earth toward the Sun, at what distance from the Earth will the gravitationa5r(f,s0.d qfo lff pw-l 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 Moone 6zt6i2b l.(m7domda 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 fo;f zd1 wufdb:zo4 6(cwm9-9xysj8e ij r a "space-walk" at a distance above the Earth equal to the radius of the Earth. What is her acce j6oswem8-ybzfuiz 49c;(wd1dj 9f:xleration due to gravity?

  The radius of the Earth is R. At what dispx.,kfp0 qc4 ffa((o 1fm:tyemxv 8s4tance above the Earth's surface will the acceleration of gravity be ((exqfcs8,fx.:t k01 mp4p4vmfoyaf $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above itppw )57 oys,*3:jfr3 p;w+k0xdmel aqf)kcu bs surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite,app;kfoy,qbx5d+*fs3:0m l 3j eu r) k) cwpw7 as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km m )ep*aup;:t6 igov3lfrom some planet's center, the acceleration of gravity alo;p ig6v*: 3pue)mt 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 the surface oxowv / c,n-; 4jircd-af je9.lf the Earth. The Earth has radius r. If the object is raised to a-jjcx-i.rwaln d; v 9f/ec,4 o height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the gply x/ry 1a35q ew,h em*;k+xweight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Earpx *ea+5lyyhm;,r 3e1/ kxwgq th is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A six c8y, c y-h0t8sh1lsatellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satellite's weight?ych 8y8ct 1sx,hi- l0s

  A spherically symmetric planey ,ve,60p e c:(mspgjpt has four times the Earth's mass and twice its radius. If a jar of peanut buttpjepcv6s,e (p m,g:y0 er weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same line, wityne .mh *+t1poh the Earth between the Moon and the Sun. The Moon han.t py o+hm*1es 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 ,;w,d)u8ed7adsc my b 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 abouw5ne6 i1 4r0ymbt7ropi:/k q pt the Earth (i.e., it just skims the surface of the Earth). What is the speep k76r0ym4e npbiiq 1two: /5rd 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 Earti: +13 q.re1;oc xg7g zreq ospfnb(0ch (i.e., it just skims the surface of the Earth). How long does it take to onr:eies. r o;pbgq1+031 fccgq7xz( 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 thett1ezeqqx lowz o kw (+,5t(2gdd*+h8 Earth. It is obserk*(e+oe (ot5z w+1t,h2 lxqd dgwzq8tved 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 orbital diameter of5. tbl 0cf,o4knbvzf /3otsmr7d s20z $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orbits the planet with fua+) h fl w7b9xrkb2204wdiva 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. wl vs/8n*s3pa0e8m zl( suxc+Moon A has orbital radius r, and moon B has orbital radius 4r.0 p wue*lz8s/msv3+l(ncax8s Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 584wk 0jojn9hb m*wgf$7.78 \times 10^{11} \; m$ 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 p. q* nii 58lxd+ 0egmv2xi.zpaverage distance from Jupiter to the Sun? (The distance from th l2. *g8+i5m.piv nixqxedpz0 e Earth to the Sun is $1.5 \times 10^{11} \; m$.)