Is it possible for an object moving with a constant speed to accelerate?ip1inf5 c81/1 cz myrx54cemh Explaimhze1cf ry4c/1pi5x5 m18incn.

  Consider a particle moving with constant speed such that its 674tannpi so5a 1-)erwzyw2d acceleration of constant magnitude is always perpa7 nyoze5 -1aiw24p snt)rwd6 endicular to its velocity.

  An object moves in a circular path atve .ai ax1h,dj juf0z/ .cm.f9 a constant speed. Compare the direction of the object's veloci.d ,aei9ujmax zf01c./ h.jfv ty and acceleration vectors.

  When an object experiences uniform circular mot+ 09pkebv nh (ve.qz;;p)feqz7t1tnx l, ol*p ion, the direction of the acceleration i;vf(v +0q npp 9e;.p*tkbz ,heeo7nxzll1)q ts

  Consider a particle moving with constant speed such that its acceleration of/g(q r/ zng.sow lk-b rdg0f71 constant magnitude is always perpendicu./gsg/qo-rrb70 kdn1 l( w gzflar to its velocity.

  What type of acceleration does an object moving with constant speed i1))g/ fnie9u5fky ayin a circular path exyi/g)1k 5fiay ) fneu9perience?

  What force is needed to make an object move in a cixd,isk uuaaz(q4g f. 1, c ;mv9r+mw1urcle?

  When an object experiences uniform circular motion, the direction of the net foraicy8:g 13 gmg fn,yn5oz(cku( e*5ph ce ieuc5, ay p( (icf5hm13og n:nzgkg*y 8s

  A roller coaster car is on a track that forms a circular loop in the vertical8;2 o2drupt5thv:v og 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 accelerogv2phv 5to rud8;2: tation at this point?

  A roller coaster car (mas,wv02up1bl o jmbl rn 8m,3i:s-im,xa s = M) is on a track that forms a circular loop (radius = r) 1o:m8 s,l2j pv30bb,mx mu,nlraw ii-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 point?

  A pilot executes a vertical dive then follows a seminl8 vxl mu 0 tljj1b5f;-73ofz-circular arc until it is going t j1l8 fo7-x0 nmlfz35vjbl;ustraight 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 curvw fl j+f43n6pze 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. v6;e npgh*j xk 9 y;lg7o5iks/ Then it goes around the same curve at half of the original speed.n lsh ev/ i;kjg9ogkpy6;7x 5* 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 constaj+b(t b-fggyft n29;hnt speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on f+t(gjfbtb2h ;g9 n y-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. If the royll x /sk6tx,jqp2(7f ad is frictionless 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 magntjfs(x p/ q,kxl62yl7 itude to

  Two horizontal curves 037 y1hi(pvvyqlt0r xon a bobsled run are banked at the same angle, but one has twice theyit v1hx vlr0q y3(p70 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 safe speed on the larger radius curve?

  The banking angle in a turn on thec2c e:8vo rk s:jtvl5; Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out: tko 5lcjr vvsec8;2: of the turn. Why do they do this?

  Is it possible for an object moving around a circular path to have bo gk)lo jsqzue12g076 dth centripetal and tangenti) jzg d e2sl7k1q60ugoal acceleration?

  The gravitational force between two objects is proporz(6t un/p3le wtional to

  The gravitational force between two objects is inversely p9(eu43g ccx firoportional to

  Two objects attract each other gravitationally. If tomgizpzr-m,q)tz mi) 17( e crg2m0d+ he distance between their centers is cut in hal m ,i g(toez zgr0q-mmrpid1 cz2)m+)7f, the gravitational force

  Two objects, with mass)v *4viu 0eaxi nae/6zes $m_{1}$ 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 w ;qkh.j9-(vhm vsda8es $m_{1}$ 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 uvk 6z3 6zdb+hgniversal gravitation.

  Compared to its mass on the Earth, the mass of an object on theihdqev k5( ),w Moon is

  The acceleration of gravity on the Moon h jn3)d+ 9+m.vvev;pkynfn; xis one-sixth what it is on Earth. An object of mas n;p jm)3xn.9 +vd vnk;fhve+ys
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves awayo.v;p9bt7p yw from the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what poinr7 2: 3t7fcahk2x:kmcd,vsy w 7p1-yby+ jlvnt is it beyond the pull of Earth's glm2y-7ywy jxkckd:v np 3v 2a,b st1+h7f:c7rravity?

  Suppose a satellite were orbiting the )d+0z bogwx4d Earth just above the surface. What is its centripetal acceleration?bo)zd0 +d4wgx

  A hypothetical planet has a mass of half that of the Earth and a radg *x,+t3vhj-d jmc,p qoj62 fkius of twice that of the Earth. What is the j,jvgo2-k hc ,j6xq m3d +pf*tacceleration 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 unw45 9)e1z aol onq*pe :vwl+on Earth. The radius of the Moon is one-fourth that of the Eqoul5 4) :*ew9 nnzw p1loea+varth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the rad4e29w i *tvq64 t(bisfv9z irdius of planet A. If planet A has mass m, what is the e v 4z*6wi2 b94v(rif9tsditq mass of planet B?

  Two planets have the same surface gravity, but planet B has twiri q05.ncb a1f*rv5ao odvj: 0zs6o(wce the mass of planet A. If planet A has radius r, wh fw av5(dvrs*5rinz01jo :baq6o .0c oat is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a so.6ck sm91: k4 l 1rdpmrqxqvi(zp81o pherical planet (mass M). Which expressionp 4rm1.p rsl6q 8 d:qk9v(icomx1 zok1 gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellitewl(kopo em(mb7bnnk8p*.r 5w m 5eo40 B, and rotates in the same orbit. Compare the two satellike55*n(kpombo(pmw 7.4 remo lwn80b te's speeds.

  A person is standing on a scale in an elevator accelerating downwardk0q8 1+d6 f mqik fzo2fwu6.qe9ubdsu(9c: lu. Compare the remc ib u.dfqqf +ku9f6uw e(2klud1q690: z8 osading on the scale to the person's true weight.

  Who was the first person to realizeiwrtoga-4klb adk cn-:5.;c 4 that the planets move in elliptical paths around the Sunr; 5:wnc4 glkto4d-.c b k-aai?

  The speed of Halley's Comet, while trx)6eo:6n) im4jnf jph 59gbnvaveling in its elliptical orbit around the m jjx)h 6og64nie9nfnp:v)5bSun,

  Let the average orbital radius of a planet be R. Lz: f.zd4os 6d.iu5pxtfv1sf5et the orbital period be T. Wfizsvd654 d.:x.uzps 5f1o tfhat quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, with 2d9 dqmpbxys, ,gk*3ythe same orbital diameter as the Ear d*y9pd,m2kq 3 ,ysxgbth 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 Earth to the Sun is define 2-9s,)boihup tj)ylm d as one "astronomical unit" (AU),- 9) j h)ipo2tsmylbu. 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.n/ p:sy0ozz :b

  List the four fundamental f9r 0,j j.rvvbporces in nature.

  An object moves withzes4p ft s.yw(u e94m0 a constant speed of 30 m/s on a circular track of radius 150 m. What is the accelpe9z(me wftu s4s4. y0eration of the object?

  The maximum speed around a levgff.asa3tu7 djn;8gt/3hpp 6ftt a10 el curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors rem/73pf0f tg68 ja;pu t3 a. stn1tdghafain unchanged.)

  What is the centripetal acceleration of a point on the perimeter zq8n ct3k.j ccw376 owof a bicycle wheel of diameter 70 cm when the bike is movin8jc nkct wq73z .3wo6cg 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s6i k gki y0uva(d.(ga*pobk8wm2h* n2 is located 0.200 m from the axis. What is the cena.i2k0ywhbovn*dug a8* pkmi6 k(g 2(tripetal acceleration?

  How many revolutions jo 9hryi81mu7-f(nr c-3 kiufper minute must a circular, rotating space station of radius 1000 m rotate to produce an artifik o-rrn-1 f37jyum( iu8 chfi9cial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn m*okcd e hr.t48 zop22at 96.5 km/h. What is the * kdhrze2t4 2c.o8mpocentripetal force on the motorcycle?

  A 0.50-kg mass is attached to the endmyg. 3jm0vo9cio2k nxl-j18lsy 0ty ) of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. o).v9njxt21c3m y08ik j yo-lglm 0ys 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 sg 8 vzq,,ozn )m*godp.;m u6zttring and whirled in a vertical circle of radius r. At the exact top of thpn;68omvg *dum,z , )qgozz t.e path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is u-ufqwu30,w lia 3tr7attached to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the paaiw7t3wu0f q ul ,r3-uth 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/sf51*b q(mwl ax experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvatu 5*mfbalw1(xqre of the loop in which the plane is flying?

  A pilot makes an outside vertix20ew74.(k ji c6 8 mm ot d2dzjny8:om*yfcntcal loop (in which the center of the loop is beneath him) of radimdzt0e27y 42 j kt8:d(oxcic* oywmm6 .8n jfnus 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 ca7q9 g n* atxahbp-,s5dn stand is about seven times his weight. What is the minimum radius of curvature that a jet plane's pap-gstxdb *ahn9 75q ,ilot, 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 hor;xlhtw9v. 1 ynhn(+u w8lb)fmizontal curve with the tires on the verge of slipping. 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 shy9);(8.nfmnw1 uh +lw xtlbv urface.)

  A car is negotiating a flat curve of radius 50 m with a speed of bee.:n ld,n6 gle;ddu ze u pf/tf41fsh3b:7*20 m/s. The centripetal force pr. udbf1s7dnl 3/ ;l ebet,: zff4pgnhuee6*: dovided by friction 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 e)w/(gxx**i *udefv r 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 tur *er(gi/ewx* u*fv)xd n?

  A car is moving with a constant speed vqd19xj6 rt5h*.z(1ye3i:hta cwlaed q i js,0 around a level curve. The coefficient of friction between the tires and the road is .,x1de1hw(5 *i er9 :ilc jz3daqt ah0yq6stj0.40. 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 to negotiate a hal w3 *usg8/6gu5 u.iy bmcf:100-m radius turn at 3.: 6has3u5ulfyg /igubw8c*m 5 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled runep8 ban*2(d s 0-izeai *z+trd0r ros( 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 radiusw.no3wz7tcvnw q4 1z ,1ia6x t 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bqoq ut pbgbw3-bk +ox8x07lu: f--q;vanked 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 uniformlyy 8tal(32cdjhhmf g,)lv(0 dy in a horizontal circle o2yd0 fal8j3)h((gv t mcd y,lhf 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, a race car accelerates at a uniform ratnp o:y3a,ijzean +r6 6e 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 blank6a 6rn+3yo: zaeinj p,s)
(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 s cy-h/ g,*pjw0v x mgr3eo/(lgx4xe2$1.67 \times 10^{-27} \; kg$ 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 ove2tu3h,e; 8 qr-jxapn a 70-kg person standing on the Earth, due to the Moon?tq;3e x u ,h-p8e2jvar 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 masses arepxrk9 nmsf9tdb:4 z):.qgwtr:) s5 bc moved to half of their initial distance,5)bdnpsk mtx4bg9sw c: qfz) r:r.9 t: what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, ag+3hsum :.ira-i gb 8sm8f7bs t what distance from the Earth will the gmhs +ir- ui78f3m.gsg s8:b baravitational 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 m 3 ecjggd,kd;3x, ;pc$7.4 \times 10^{22} \; kg$ 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 ab16t: vpn:l +pii rc6zy2 pn4szove the Earth equal to pzl 66rv124i spn y: n+:cziptthe radius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above 5 y-bk7wfdxe,b c9go-the Earth's surface will the acceleration ofe5k7b g dw-xbyofc 9,- gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its suruo-gzmlw 7y(gt/ sg +hu7 /7m11twys lface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the accele+wum1 71yl-(/tg w/7mz7 su ylho gtsgration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of gra;:t7w/ b5bzy aniz2rzvity isbn z725yza t: z;rb/iw $32 \; m/s^2$. 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 radius r4hvz8 lpld76u, p)vt k:gn: qz. If the object is raishpz:vt p:k)qgul8 4l7 vn, 6zded to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does thea9(pdl-j49 j2x/q9z jcccepx weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The c9/ pxpqj2 z-4(xaj 9cdcjel9mean 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 3 5v oupng; jz+ti6y5+zr above the Earth's surface. What is the satelzzvi+;o+ 56u g5tnjyp lite's weight?

  A spherically symmetric planet has four ,9 1zhxp crx6 ta7*ummtimes the Earth's mass 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 surface of thmc*a t r,x6hu79 pzx1mis planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on t+-ahauft,szph o;s hs0gva9r+ , 1)pxhe same line, with the Earth betwgp+1 o9)a,ssvh+ saru,zx 0pt-; hhfaeen 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 transport 2 e/l4i0ogoa gqt00aued 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 obw1hf/ pplm.cmtm4++ ia - j11xbh2y about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of the Eart+ m4 1j-h oxw1b1cfpiy+ b2m h/tap.mlh is $6.38 \times 10^{6} \; m$.)

  A satellite is in a yhu7 5+n dl2m .tlz51 a-xzzcalow circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make nlzh 5+-u .7z1myalxt52da zcone 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. It is :ek;jto a0w+zku8 4zrrz2 g(qobserved to have a period of 89 min. What is the mass of the Earth? (The mean radius of the 0z28kw+qj; ag e:ko zru z4t(rEarth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamebubgg ,/x nni-r. ))lrter of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of kby :5qid10dmu .qfj-Jupiter orbits 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 circunmic o y- h:tv/.y4h2clar orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. Ho/.h-2 yc vm4cy tnoh:iw long does it take moon B to complete an orbit?

  The planet Jupiter isyi 0;bg12g(an 0zuf l 1tr7phl $7.78 \times 10^{11} \; m$ 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 avedivj8/mgl9ln 0: . yfubh4+f; 7vwbi yrage distance from Jufy7uy.bbnlvw4g/0 dim ; l8vjf: 9ih+piter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)