Is it possible for an object moving with a constant speed tvxh. n x(i yl-zhgz6:s:hk 3g6p/yub /o accelerate? Explain.-sxg :pbzulny yg h x/:6v(/ hk6z.hi3

  Consider a particle moving with constant speed such that its acceleration of con tego;,(uevs6 stant magnitude is always peesut ;(e o6,vgrpendicular to its velocity.

  An object moves in a circular path at a constant sp96 byb5dgy5pf eed. Compare the direction of the object's veloci 5pb59yb6gyfdty and acceleration vectors.

  When an object experiences uniform circular: .a t3js3 tqt9cq/.fao :guam motion, the direction of the acceleratio qa:/3 t3qtam autsfjgc .:9.on is

  Consider a particle movinhacxz7:x(qs* :jg.py g with constant speed such that its acceleration of conss.z: *cpa(h7:gx yx qjtant magnitude is always perpendicular to its velocity.

  What type of acceleration does an objez bos ,d9q f,r47 mnr)7 dfmfb(ypg+f0ct moving with constant speed in a circular path exper ydf, bz )d47mmf,0p79o( nf+gbrrsfqience?

  What force is needed to make an object move in a circlej9r 19rvib-c l *,d8rto)b ghb?

  When an object experiences uniform circular motion rnvj11b.nq8w, the direction of the net force ibw.1nv81jrnq s

  A roller coaster car is o:n;)yp0nc +vmki3j orw d g)f*n a track that forms a circular 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 valjp i d* yfnk)0;mv)cr3+gno: wue for its centripetal acceleration at this point?

  A roller coaster car (massvpf *a;x5(fbt 0as)nb = M) is on a track that forms a circular loop (radius = r) 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 valuefxf)0vb5(pbans a*t ; for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circulpo m**+u1lohvr c*s d9ar arc until it is going straight up. Just as the plane is at its lowest pou 1dp*rsm+lc 9o v**ohint, 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 cur lw/jpof*4oiyc; 1y4fve 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 0s 7yfm-y /x psffvi67speed 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 vff-0sxs7y m7/f ip y6second time, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it glw- quaev* 8+jc(mh g)oes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second v-l8 (awej* hqgm+uc) curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with speed v. Ifll k:z-l b8 iuboi2g )k7oc7j. the road 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 magnitudg2kz k bi lcbl)-o:7.7ui8jo le to

  Two horizontal curves on a bobsled run are banked at the same angle, bg iuu*t*na06h ool 1+a -nx 26qmctk/x3gn1ap ut 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 safe spee2 nx 1gho*6lqm6ua/t+ua 0 knxpcaio1t3*g-nd on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled2 dt;qet:u. )k dlqeg8 track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wadeq.d tle:2)uq8gt; kll," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object movi jt1xr ogn dn6 rij+no8q mx7fb1)2x.)ng around a circular path to have both centripetal and tangentqd ifon71 tn21x)grjobn)xj .rm6+8xial acceleration?

  The gravitational force between two ob :x7eac5sghk/a v9zv d )1m5upjects is proportional to

  The gravitational foyn-y*3at1ig vv;;uys3pcy8 b rce between two objects is inversely proportional to

  Two objects attract each other gravitationc03ds969er1hd/f gnn sp,)s .sfxlz:yw jx c 7ally. If the distance between their centers is cut in half, the gravitational fors9cpdn sx.9s0)7zdfn 1xyrg cwef /: s h63jl,ce

  Two objects, with massh4 ./qjo /zoppes $m_{1}$ 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 maqxgi(fk0 ( 0oksses $m_{1}$ 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 graviiqbipd87 mv)g1z8h7 htation.

  Compared to its mass on the Earth, tu40om-8o2;o ca8j 9 02tis n-fdc l *plzxmshohe mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixx 7w:yy zu3f7xth what it is on Earth. An object7xz7yfyu:x 3w of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface,9rhx m.w-dkre*.9f-nii7 by r the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the p(8oog d7gj sk-d0yan 0ull of Earth's gravity?7-d jk aoo080sng(d yg

  Suppose a satellite were orbiting the Earth just above the surface. What*at rta1k9sq : is its centripetal acc rs1a:a tt9k*qeleration?

  A hypothetical planet has a maovr8vo z-0o 3ess of half that of the Earth and a radius of twice that of the Earth. What isozvo8vo-0r e3 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 onyud eq*go., i*e-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon',ed**youq ig .s mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the radius ;1io m+kva;dxof planet A. If planet A has mass m, wha+1 ik; x;vmadot is the mass of planet B?

  Two planets have the same surface gravity, ocbgkhl;q(5 3.ubi6 ubut planet B has twice the mass of planet A. If planet A has radius r, what is the radius of phu6(bl uig ;bk5o qc3.lanet B?

  Consider a small satellite moving in a circular orqx-vfbowj7/d( z) xz6bit (radius r) about a spherical planet (mass M7 6x(-woq/v bf)zdjx z). Which expression gives this satellite's orbital velocity?

  Satellite A has twiceitligd o 77q:au+n lh5/t)3 vf the mass of satellite B, and rotates in the same orbit. Compare the3t:/lvqd+) h7iiugfo5 7nl t a two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downwarqzm 3m0ie j y)zh+iqn9 kj2y*+d. Compare the reading on the scale to the person') imqz n+hj0 kqime2 9*+3jzyys true weight.

  Who was the first person to realize that .g gz n dw3w//itryi4(4scmaz,;v 6iithe planets move in elliptical paths around th g46.d w,ri(v/it i/; ingzz34ysa cwme Sun?

  The speed of Halley's Comet, whil7fe ngno.crp)73tahp.;9tq c e traveling in its elliptical orbit around the S c7tf93.cprn gt. ohpna ;q7)eun,

  Let the average orbital radiusm(7xp )xqoz 4x.ij ,qt of a planet be R. Let the orbital period be T. What qu)ti7qjx omz4 .p(q,x xantity is constant for all planets orbiting the Sun?

  A planet is discovereb5r.qo** rksvur:;ix d to orbit around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 ti rb kxs i.;q*u*:rvor5mes 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 tpn6wlnne9( p5ih, (mu he Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the astem(9nwh5e,nipnl( u p6 roid's average distance from the Sun?

State Kepler's laws.u1*)8vma ooj nkv )*vg

  List the four fundamental forc.kr 7 /th xz7h)kq-,grdr wkg.es in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radiuigy o b/.8* tz w98fax)ey1mnds 150 m. What is the accelerattz98 81/*a wey .go)xynbi fmdion of the object?

  The maximum speed around a level curve is 30.0 km.3p0ceymd 22 jzil)y1h2m li i/h. What is the maximum speed around a curve with twice the radius? (Assume all cid2h l jyil.y2ie2)zm03pm 1other factors remain unchanged.)

  What is the centripetal acceleration 8 qf:ezu do0mo4 /f,x xma8ga:7v rri0of a point on the perimeter of a bicycle wheel of diameter 78x8o:d4a m 0:um,e7f0rxrio/afqzg v0 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00n :6. bsocw.wh3ho d(z rev/s is located 0.200 m from the axis. What is the centripetal accelerati .d( b hc3owhnzw:so.6on?

  How many revolutions per minute must a circular, rotating space 7x4(b- rx2sx )tnaixfstation of radius 1000 m rotate to produce an artificial gra-( i4r7xantbx f2)xsxvity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 2j 3mm+mqnt3zy+l( : kk50 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the mo3nq t+mjk:l km( mz+y3torcycle?

  A 0.50-kg mass is attachojv .88ok+vimrh3 w0n g 8djq*ed to the end 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. What is the maximum speed of the mass +nq0 d8m.joj*g oihvr 88vwk3 if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a vertic/y1bo5uu-mpn y6 linwd 59z3hal circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight.5h/imbondyy935 nu16u -pzwl The stone's speed at this point is given by

  A stone, of mass m, is attachelz. ynn m//7cil)q*lgd to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tensi7// cq.g* lz ymlli)nnon 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 experien hmu.89zr04unsb y um2ces an acceleration of 4g when pulling out of the dive. What is the radius of curvathy.b8 z2 mu94uu0 rnmsure of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in-q3fr9lllelt ;+ m7tx 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 one-hal;qll 9llmt rxeft-+73f of his normal weight. How fast is he going?

  The maximum force a pc4 1 fl:uoqj 60r)goemx-3m )nk83qdd0toxyg ilot can stand is about seven times 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 3k8dx -)1x6gljcn0:uyeogq 30 fmdm4to q) roof 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal c8j4oboyt:h w 5l54hz gurve 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 cho 8ogz54ybt: j4lh 5war's tires and each road surface.)

  A car is negotiating a flat curve of radius 5096dfgpkprl ee oh .7;. m with a speed of 20 m/s. The centripetal force provided bfpeh9pod;l6.r 7. keg y 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 a speed of 14 m/s. * pxckt svbm3i30 )m*mWhat must be the minimum coefficient of friction between the tires and the road for t0vk3 m** 3tb mci)pxsmhe car to make the turn?

  A car is moving with a constant speed v around a level curve. Thef1xz1 ,vm t,jwq9 ovy/ coefficient of friction between the tires and tvqjf , tx ,/v9o1myz1whe road 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 bakb-3 m3 5d1vn zq1gadobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignord11nd3g -abvq mk z3a5e friction.)

  A horizontal curve on a -nm:zdke , ln+,3vdx bbobsled 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 radius 100 m, banked at an angle w9ij zd:*qt6v of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m uoo :czt2l-*. h8 ghh5dyt+z. iefrm:is 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 strino;bv;xl p py /ndx:s6 9e20wfdg is revolving uniformly in a horizontal circle of radius 0.500wy;dp6 0 :f;eb/xlsx p2n9dv o
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 accelera mczplve20 o4*tes 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 numerpmol4*e2cv0 zical 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 conswn2 d.sg/ 1*lxebpf,1jj :aosists 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 p+7f;06qa:x cz qrpxhq erson standing on the Earth, due to the Moon? The mass of the Moo:xa+cpzhfq; 7x6 qqr 0n 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. 6:4gk-7x t:u s rtct sszcc5;y If the masses are moved to half of their initial distance, what is the gravitationaccgt4yz5;u:x: s tck7rsts-6l attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance f9r0l+,*r.15x aecqtg zli awnyfx5+nrom the E *ceyn9trrx5l 0+5 l g+ aaq.,wi1fnzxarth 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 Mooni83k jt +e(xzh 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 equal t. 9he1 sfs(da/wq8c 2 3dedjgco the radius of the Earth. W8/ .a2 s dj(hwe9fsdc1de cq3ghat is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface we jz-, .7kry5sxgw7)c 7swro eill the accel rjgkree s5-c,s7xww 7y7o .)zeration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars aw /oz.e3b 3luwt a distance above its surface equal to 3 times the 3/bw3lzue ow.radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14008vi hw5dtpk,00 km from some planet's center, the acceleration of gravity,khtwvdip0 8 5 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 of8(gs flu) x) o db8d(cy.cxqwsok pz2ic05 2:k the Earth. The Earth has radius r. If the object is raised tox0ugpsb5f)c) klsi82 2(yq c o w(dkdzx:.oc8 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 chang wvtd 29z7j(a1u0upuoe when he goes from sea level to an altitude of 5000 m? v zw21up7(u taod9uj0 (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite nc,ucl ic5 41uof mass 100 kg is at a point 3r above the Earth's surface. What is the satc1l5cic u u,4nellite's weight?

  A spherically symmetric planet nu 69bjb5pc ;whas four times the Earth's mass and twice its radius6nc9b 5wupj;b. If a jar of peanut butter 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,b)ms0x (wnlo ; Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. nb0 ) mx;(solw 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 the Moon. h*b1 ouiuku(gxe965 j
(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 6b.a ,apy q2k th7v2amsurface of the Earth). What is the spa.a kb67q hyma2v,2tpeed 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 Earth (i.e., it just kn+ojay*/z9jxm .,b1 ntmh-l skims the surface of the Earth). How long does itx by , 9.-n+kjjman/thl1m z*o 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 above thq z.7v-g5 z9gwmjo8 rb ii.la1o:i u;xe surface of the Earth. It is og.7oi oij;v :x9w-lbu1rag.qz zim85 bserved 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-joutc(iil+;e v 4a 1 f oc3lkceio186 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 them f5zp3 )d5aqn 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. Mcce/x j)v/x7k;fc0a eoon A has orbital radius r, and moon B has orbital radius 4r. Mcee 0xx/)vkcac7 f/ j;oon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter iskr,x vvo y .6y9(w)kep $7.78 \times 10^{11} \; m$ 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 dp 5s*0 3 ak0ba e-rhcptbpw4 ue;lsw.s4yw2*to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distances swr.a*hd 5a4l0et20by4 ws-e*ub3 pkpw ;pc from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)