Is it possible for an ,l,peqk )b0fdobject moving with a constant speed to accelerate? Explain)bdpe0q,, fkl .

  Consider a particle moving with g3b cu cdx-wfbr-:. zvz:-+evconstant speed such that its acceleration of constant magnitude is always perpendicular to its ve-:zvcb-vcwr:x eg dz.u3 +fb-locity.

  An object moves in a circulg..h fo,fzu+ xar path at a constant speed. Compare the direction of to+x.uh , gzff.he object's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the accelepa g( a/bd6ua,ratau(apbgd6 a /,ion is

  Consider a particle moving with constant speed such that its acceleration ougae ; xjbx,68c yqlxzkc- faw u/odw;84+t)5f constant magnitude is always perpendicular to its velocity;tuxw / ecxqcojuz4w ,k)d8 agy5+xlb ;fa6-8.

  What type of acceleration does an object moving with constant speed in dr(a4:q2:pku*4 bziu nzns pxk81 he8a circular path e :4u42 qbz z88ia( drpuhnk1:sexp*knxperience?

  What force is needed to make an objevw+ej+9hsy o j1 t:7mrct move in a circle?

  When an object experiences uniform circular mottvu ktfl4ol:u+i1,or; ,5 cvjion, the direction of the net for; ,+,u:4ortv lo1ivfkcjt 5ulce is

  A roller coaster car is on a track that forms a a/0 sb/wip q.myhi8 +tcircular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value for its centribqsahi.m/t y/ +p wi08petal acceleration at this point?

  A roller coaster car (mass = M) is on a tra q6qaohv k/6)tw.s 3cmck that forms a circular loop (radius = r) in th6./ksm wctqh6 av) q3oe 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 semi-circular arc until it is i1nv 0:6-znwtum:v 322 nr navgx xv.rak*z 7igoing strzv* .173:vnvai 2arn -t un:0 xkv2gzrw6 ixnmaight 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 curve of rad-ze: vtj:otd8 ius $r$ 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. T:ek0.z9aks),bn 5h ec hxbqa 0hen it goes around theh 0 a 0 e.)k:kbe5ancbqz9x,sh same curve 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 dxn2 hdm )+jmjh1( zl)mypjyz)y69 a)curve of radius r 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, 96j)zzxyydd+nm)(j lp1jy hm )2ahm )compared to the first?

  A car of mass m goes around a banked curve of radius r with speed v. If the rou;;aspmy agx4-b 92q3e wm0idad is frictionless due to ice, thexa3b2ai4; y0e;udws qmm9gp- 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 curveomui u,. wne;;s on 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 swum.;;,iuon e tay 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 4..hw1fguljri 7bbar r; ql18 constant, but increajq 181rbgllauir;f b7r.4.whses 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 h4uuqt c b-84yfave both centripet44t- qyu 8ufbcal and tangential acceleration?

  The gravitational force between two objects is proportih/aym89fs3r3f js 4lzonal to

  The gravitational force between two objects is inversely proportional kl*9.m)l z p1defi)jj+kbx3v 9sa 4 nbto

  Two objects attract each other gravitationally. If the distance between their (ip2;2 vm 4(u6rr ;x j x2vrjgaicxd(vcenters is cut in half, the gravita;2ig ( vr4(x; c xjmvj(2xpri2uav6 rdtional force

  Two objects, with massefau9 1 wa)p/css $m_{1}$ 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 mapx sk3ylu+7: e aab.w: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 gravitatio3ha d +b0sh7aon.

  Compared to its mass on the Earth, the mass ofns2zv.2 ;:ovuzew8a b an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it isq;eaz ls-+;x jq3dz1t on Earth. An object of1zd;z eqt jsx-lq;a+3 mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rol4.xeh(vk 7r vcket's weight

  A spaceship is traveling to the Moon. At whattyoxa4fv 06k hnl0k0: point is it beyond the pull of Earth's gravity? ftyx0 k40kh: l6va0on

  Suppose a satellite were orbiting the Earth just above the surface. What is 9w ejk;qr.cy4its cen ; wqecjr.4ky9tripetal acceleration?

  A hypothetical planet has a mw y8y* ik2ilr*ass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the*yk8rly2i*w i acceleration due to gravity at the Earth?

  The acceleration of gravity o8e3.cy *hbgmq9h1kid5 kky a 7n the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mas h*9key.byqhkcgaimk3 71d 85s compared to the Earth's?

  Two planets have the same surface graviz-uo/dfv2jhj( o e7 dmr49+ja2wiwtzpt t:59ty, but planet B has twice the radius of planet A. If planet A hasiue9jv zhw54m2 +r t( 2/a 7f d:todtpjzj9w-o mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice the iit86wo ktb*z(h.q w/ mass of planet A. If planet A has radius r, what is the radius of planet hiw.q /(tt8oizb*6 w kB?

  Consider a small satellite moving in ain+a3omz9ys wxmq4 -9 z*oi6t circular orbit (radius r) about a spherical planet (mass M). Which expression gxwsi3*y6n -oaqz mi+tz 94m9oives this satellite's orbital velocity?

  Satellite A has twicm m m) ,h,cwt5.kzx)lkq2- sxje the mass of satellite B, and rotates in the same orbit. Compar mwmj ),z-,s.kc kqm5xx2lt)he the two satellite's speeds.

  A person is standing on a s ze;otd1a0e . oiw;4q3,p( aujhn)mfxcale in an elevator accelerating downward. Compare the reading on the sc;h dqtzaj0xn;) ,u o(afie.14w op 3emale to the person's true weight.

  Who was the first person to realize that the planets move in elliba h*h* zxno;1ptical paths around ho h;nx*b*za1 the Sun?

  The speed of Halley's Comml1( u,:ob fmaet, while traveling in its elliptical orbit around the Sun, mu,l 1(o:fbma

  Let the average orbital radius of a planet be R. Let the orbital period 34(z0u psajy5np zj7lbe T. What quantity is const3 anlp5yzjs 0(j4pz u7ant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, wirm)pt3 2ejmf 9th the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass9p 3)jf rt2mme 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 defined as one "aggd*m l 0r39klstronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid'rll9d0 k*gg 3ms average distance from the Sun?

State Kepler's laws.q:y d,t4ti cg(

  List the four fundamendo m;j(r+zn0bztn h -(tal forces in nature.

  An object moves with a constant speed of 30 m/s on a yf verkjb- zz*7q6g33circular track of radius 150 m. Wha-rk3z3 ej y*bf67zvgqt is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. Wh,pad wagr+zl h z,e590at is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchan e p 09,adlzw5zh+ar,gged.)

  What is the centripetal acceleration of a point on the perimetegs 7il-+k-xubr of a bicycle wheel of dib+is-7l gkux- ameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.451s kk.vvke0ws*es g5k* rlu200 m from the axis. What is the centripetal accelera*u kk *e ves41lk55 r0ksgsw.vtion?

  How many revolutions per minute must a circularcek8 -*fu.dbkvjf ye*d l(,pp p.3a3 y, rotating space station of radius 1000 m rotate to produce an artikv3uc *yl dj (kpede3a* -p8yff.pb. ,ficial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It gop hic- 9r:p fz(f9md5ees around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force ecfzp9 d( f9h:mi5r-pon the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The systehw,l;py+t:b nm is whirled in a horizontal circuly:wp h;n ,tb+lar 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 attache( tj7--(drp yey 5jzksd to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in the strytrj- 7d(5 y(sjzk-e ping is 3 times the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong sr .-jt ,ets6b efu7ox7y3d+adtring 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's weig ,b .e63add7ujo tstxerf+y7-ht. The stone's speed at this point is given by

  A jet plane flying 60i/ ya-p.x*m; d;k y7hdv1khsa 0 m/s experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the iyyh kadp*;sk h;/ax dm7-1v.loop in which the plane is flying?

  A pilot makes an outside vertical lzki /s1 xqnl2,b4z8e em6a kx5oop (in which 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 l6ekm xzbxnek s 1 4,85iza/2qone-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven tu7y6*xia-lx gdsko61 imes his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 25-oag16xuxi7 dk s* 6ly0 m/s?

  A car traveling 20 m/s rounds z 9v he: hyv92i5r53;d;p jpxwnsfg6ban 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car rounnp;g3jyv h5zv9; 2rfs9hwx:e db6i5p d 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 20 m/s. The cen5lbzel23z6b qv9ivc-0l abfx t6 v3l305zl - ibetl3lvx3q23 6bv za6c9lbvftripetal force provided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radiuh.)kmf b w97ysnhcb;8s 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 b;.)8hf h snc9bmy 7kwturn?

  A car is moving with a constant speed v around aek q qp:q37/1z 5aausg level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay on theu az7/q3skp1q :5a qge road?

  What minimum banking angle is required for an Olympic bobsled to negotiad6st;d ar3tc555 z:2em. rg skuna; lkte a 100-m radius turn at 35 m/s without skidding? (Ignore fricc:3r;5t5a mlkadg .nk2s6 s d;ue5rtztion.)

  A horizontal curve onais54via3 bf tc5t(3q a bobsled run 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 radi7,a l015ii y lbuso-dfus 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i 4zsh*s(5ctzbs banked 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 rev9)3u mbxl.ed*qse.eq olving uniformly in a horizontal circle ofm *s.e uqb)xe3le9.dq 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 r/(zmy cgh9 .fcace car accelerates at a uniform rate to a speed o(mzhcgf yc /.9f 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 u3 gk/cij,,tjt94e rv 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 person standing on the Earth, due toe)jm d*lysj s:-an-6e the Moon? The massjnas d6ejeslm:-y *-) 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 t:h0ky 2y+ruk7 2uwhl ewo masses is F. If the masses are moved to half of their initial distance, what is the gruy2r2k el+whk:u yh70avitational attractive force?

  For a spacecraft going from the Earth toward t)l 8esx.g; wk xkuti)/he Sun, at what distance from the Earth will the gravitational forces due to the Sunke;uw x 8/gkt))l xsi. 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 Moony*4gz rzb;h/ w 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 for a "space-walk" at a distance above the Earth,dp k., /jro5zdln1zj x4yy,q equal to the radius of the Earth. What is her accelera.,/n14 p,jy kzj5dqr d,oxlyztion due to gravity?

  The radius of the Earth9;cievep q0p k)jfw(,h gj8 x. is R. At what distance above the Earth's surface will the xp,v hf pk;0gc)9qjewe. 8i(jacceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a jpk5u/gzvc 71 1 fe;7u j(qunz9g wv pup8v8p1distance above its surface equal to 3 times the radius of Mars. The acqgpc9 ukvvz wpe7n8z(51 8/ 1j u j1v;gfu7pupceleration 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, thg18mrcff l5+pvso+3 x e acceleration of gravity is svmpgfol 5 f81+3xr+c $32 \; m/s^2$. 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 r. If ofnn qv3+u e:zsciv(j3 h:.u -k5*flpthe object is raised to a height of3kh.q3( f*+lv fci-o :n uzue5 vspnj: 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg personbe6wgmh 3isie);kv9 9 change when he goes from sea level to an altitude of 5000v9 ebg iw3)ek;h 9is6m m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mevj.b+1l ptbn0amj 7e5 th +q6ass 100 kg is at a point 3r above the Earth's surface. What is the satehej60vmnl5t1 + 7pq.jt+ aebb llite's weight?

  A spherically symmetr+u dnhn0b+jr d8s9y:mic planet has four times 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 t+d u98 j:yr0bhd +smnnhis planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same line27m:uxkf49lz b+.1 4mssviw tzt di r+, with the xkfs.lz i4t w1tm9vzsb2:4r d++7ui mEarth between 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 ttcrol,x m a;(7j3qe0transported 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 s* .f.znuafek4f:81:n gd xgk ;aro f.mkims the surface of the Earth). What is the speed of the sate .znd k:f f8 k.emf;4aof*r n1a.gg:uxllite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it jue n p3hvoh3jmx3e+6r am6/u*f st skims the surface of the Earth). How l3*pma3 + e6/evmo6runhx3jf h ong 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 circular orbit 230 km abo9c knkt 7dfs;t-2 yy/zve 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 of the9z-ftkc/n7tsky; 2y d Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an s2r 1wqo*bjg+8z xbl*c/mlz- 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 orbitsb 4t8lj p:xc7q 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 circular orbits. Moon-s06cm(y v8w;j e .wn dezc)lz A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one ozz; (m-6y lcwsnjc0.weed8 v)rbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is ,jl*))ro x v-1gw-bgp xo6hoj$7.78 \times 10^{11} \; m$ 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 t8o7 cnjha8nhka49; gxhe Sun once. What is the average distance a88k9;nn c xohj7g4ah from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)