Is it possible for an object moving with a constant spee.jqo1 khd5s1 fd1p,f wd to accelerate? Explain.f5qj of.1pkdw1, sh1d

  Consider a particle moving with constahv jlo619do7e nt speed such that its acceleration of constant magnitude is always perpendicular to its velo1v9o7l6o e hdjcity.

  An object moves in a circukin l)..p :oeklk-av 3lar path at a constant speed. Compare the direction of the object's velocity and acca:kepvki k)3.nlo-l. eleration vectors.

  When an object experiences unifv xi.y8-lg d.gorm circular motion, the direction of the accelerai8xgdy -v.gl.tion is

  Consider a particle moving with constant speed such that its acceleraitjn5og m5e9 w,py7x7 tion of constant magnitude is always perpendiculaoy e5,x5n7 m 79gwtjpir to its velocity.

  What type of acceleration does an object moving with constant speed in a ct3d5:qd swdcc09vog( jw -k-sircular path experien(t9qd-gdowvc :jsw-5 0dc s3 kce?

  What force is needed)ohi5c 8+ervam5, 1m a; vbwh-ta.cxq to make an object move in a circle?

  When an object experiences uniform circular motion, the direction wxfs30io s43 v7kbi8cof the net forcev7ks0w48iibs3o3x fc is

  A roller coaster car is on a track that forms a circular loop j g9ix vb1o9zrb,3ya6in the vertical plane. If the car is to just maintain contact with track at the toa1 i vbz 9y9jgo6b3,xrp 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 circu ead9tzm kof77+):og vk + ab8-jhiy9dlar loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of thebj77d -: kzm9v ha+o8ofge dit)9+aky loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical9h(-u(kfrshksu a+3 g dive then follows a semi-circular arc until it is going straight up. Just as the pl f ruaus+h(9k-s(g3kh ane 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 radiusr ctg6epd (n;k/2iz7 pm9mo/.u m1 yyh $r$ 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 arolqlrd06xpn9 r 6po* t:und 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 second time, compared to the first 6 ldp9l*rqt0x6p:orntime?

  A car goes around a curve of radius r at a constant speed7s(t)hzupy /twow4e - f;--xa p pb1sw v. Then it goes around a curf/ w(yh7-zspxout swtp -- 1bwp4a;e)ve of radius 2r at speed 2v. What is the centripetal force on 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 roaszw u: ns2y+ 42i- qnf+8kgdiud 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 magnitude tow+2d s8- qiyi4z+nus k2fugn:

  Two horizontal curves on a bws*h8 qg 6*x- rmblme6r ,ch4bobsled 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 emb6 wrqs b468*hcxhg,mr* - lthe run) for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn-k /dcoq 4kpx3 rd fc-7mo+i6gr fx4b6 on the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intention3q+id gxb orop7f-xf4d/4ckm 6-kcr6 ally "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 have both centrip-- cab2ewhh k y7fbb(4eta b-2b( ca kwhfe-4y7bhl and tangential acceleration?

  The gravitational force between two obje1*hc 3g.o j+,ri5ep;qquwj;mhzt h3m cts is proportional to

  The gravitational force between two objects is inversely proprm ::b1nw kz+oortional to

  Two objects attract each other gravita:fe)tg*l8lk e n j8oz+tionally. If the distance between their centers is cut in half, the gravitational*l)l e+8:g 8knjet zof force

  Two objects, with masdx (d(r5y mf w9q9cou1ses $m_{1}$ 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 e t8prvsxff2r7 /. a)r$m_{1}$ 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 univers93 xte pj.2. )myzhoz:+k ieekal gravitation.

  Compared to its mass vy/ 2xuya5z: 3 btpd-2ho9)netc: t abmq2v-o on the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An.mgrvh;:ct0toaq :1o obmoat;v c.ot:0:r1h qg ject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away c+ 9fomo8ai7 i0(cpft from the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it cn. pw(ap(nlj22bok ,beyond the pull of Earth's gravity?pc,2a bklpwo ( j.(2nn

  Suppose a satellite were orbiting the Earth just above cwb 5vwuoa004 rh -,)0 vusq:pbv;ob vthe surface. What is its centripetal accb;wuowvpv-cbsv :05h0,v0o q 4 uarb) eleration?

  A hypothetical planet has a mass of half that of the Earth and a radius of twiculy+ut00j- ib e that of thb-uj +y 0t0uile Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravik(x m-35ktdfzhu8p/o ty on 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 mass compared to (kto kf8mu-pxzd h3/5the Earth's?

  Two planets have the same surface gravity, g:ymvcp/,z,obut planet B has twice the radius of planet A. If planet A has mass m, what is the mass of plagy om,:pzv c/,net B?

  Two planets have the same surface 5 .qch(*zq;rhisn j60y p+x vygravity, but planet B has twice the mass of planet A. If phcr0i;hnv .*(p+ 6jx5 ysyzqq lanet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular ord; 2ut/(x,6fwc a) d qsp.szqtbit (radius r) about a spherical planet (ma a,u s;xpf2.wztq d6td)q(sc/ ss M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B 8t5 (bb*vugm/5nqefo , and rotates in the same orbit. Compare the twotv/men55 (go*u8b fqb satellite's speeds.

  A person is standing on a scale in an elevator acc,:oci3icdu3z b ( wcmna-z8o+elerating downward. Compare the reading on thc3odbiza8zm 3nu (o i-c,w+c :e scale to the person's true weight.

  Who was the first person to realize that the planets move in el6 6qyhbpwk nheu.l5z:dl-,n 2b q0o;dliptical paths around th6.nzbo yqh:-w;nl qd khe2up6 bl50d,e Sun?

  The speed of Halley's Comet, while travelgsw: 1kfq 8d:*bs /xbiing in its elliptical orbit around the iq gs*s/b8xk:d w1 fb:Sun,

  Let the average orbital radius of a planet be R. Let the orbi gnak1i3e k 8mchho+)6tal period be T. What quantity is constant hoh gn6 38kikc 1a)+emfor all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the gals-gg5 jc8+w l*w u z/yo)rge.iaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of orgj u)5 gcy +*- /l8igwsw.zeour 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 "astrohd - i;mdny.u6k4f9vnnomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's an.d kd nhu64-fv;9miy verage distance from the Sun?

State Kepler's laws.8gtcm :h,t l9)-o5u uyg.zuwx

  List the four fundamental forces iz e)uzd rfj+hd2)onmd9yfx.+s2 (nl, n nature.

  An object moves with a constant speed of 30 m/s on a circular trac2z1uwx ib/ rw-6dee;t k of radius 150 dte2-eib1; xu/w 6 zwrm. What is the acceleration of the object?

  The maximum speed around a level curve isxocu p v cfww6,xf 4w2*:wd:3vu-1fty 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume cx w x4ct*2:-wu1o,vf:vfudp36w fyw all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycpy4cv mgga: )m,g.le7 le wheel of,vgl)e gc:pm7g m4.a y diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotarci x ao93 ka;hr/tm68u iye*f+41hgrting at 5.00 rev/s is located 0.200 m from the axis. Whahrxc+h61;i38y/ o9r iukm arat*ge 4ft is the centripetal acceleration?

  How many revolutions per mxx nwlg i;w*/*inute must a circular, rotating space station of radius 1l ww*;g* i/xxn000 m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at 96.py d 1j.l0z-3pj-p8nzps t 5ql5 km/h. What is the centripetat3. y l-j1nzzqpsl dp 58j0p-pl force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The systemabmql3 8dlf8n h2k,4t-sq5yg is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum qt 5,l4q-gk3lmhy8da28bs nfspeed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong stringenp wc 5ylsp,9d71v/s and whirled in a vertical circle of radius r/n5w7 deplpy,cs1sv 9. At the exact top 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 stone, of mass m, is7j :aa;qph2r o attached to a strong string and whirled in a vertical circle of radius r. At the exact b:h2jarp qa7o; ottom 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 acceleration of 4 7ua71oqvsv7kg when pulling out of the dive. What is the 71v v q77ukoasradius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in whichckd5rwzw /frb)n: (4 m the center of the loop is beneath him) of radius 3200 m. Atww)bkdn4f(z: r m/c r5 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 can stan:ksbd a6hpzgo.1d2xykk g /7(d 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 toleg62 x1pao.:k dyzhb/k7s(gkdrate at a speed of 250 m/s?

  A car traveling 20 m/s h./u ,pbahs/j rounds an 80-m radius horizontal 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 /.bauhj/sp, h surface.)

  A car is negotiating a flat curve of radius 50 m with a speed cs j;h zmk52.ijm x8+lof 20 m/s. The centripetal forcezc8k5j m+j xs;mlh.i2 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 radius 50 m at a speed of 14 m/s. Wkl2mn d;tr h75uu1k/hn:1d nohat must be the minimum coefficient of friction betwen1nukd2n17t oh 5ldrkhum :;/en the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a levewl0ql0ct2z uo;aa09 kj4l gi(l curve. The coefficient of fricti(0go2j9ak azwl;u0c0l qt 4li on between the tires and the 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 bobsled to negotiate a 10 ni6 p6ec5scrf;qxe:,*m5 dqr0-m r6rqcf5rs eqcm*xp d;n5 e:6,iadius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobf0r+lym95e: .uhb ti +6g hnjkwv 0e,wsled 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 curvet l)hhk ez;j9m2 r)9tu of radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked a08: d ytvq;gn-gqkkk )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 unifpzi f0x4w ul45yziny73kiw-0i0 qa6 pormly in a horizontal circle of radius 0.500q4 k z-nu75lap0yipwy f36xz04wi0ii
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,caa kg; adrkxiy.-7:rij5o : accelerates 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 nume j:a ckr. ,5:d7io-ayi;xargkrical 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/:gs)+ lygekpk6p :tk 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 forcewx dd wo1r/5gcz22wh . on a 70-kg person standing on the Earth, due to thed 2wd2gw5/hwcor x1.z 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 attractive force b6hi sw0.a( 0bosry9rbryrywl 5 3.j y)etween two masses is F. If the masses are moved to half of theisbar ). oy5w6yyj(r. b lhs09w3irr0yr initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Su48xe hdctt f,-n, at what distance from the Earth will the gravt-exh4f c,8td itational 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 Moonfxdk9q u8 :g422 sgogxz6z ud. 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 tc2z/g):xs/oo n9nh z for a "space-walk" at a distance above the Earth equal to the radius of the Earth. What is her acgo:znctx2s/ n/)o h9zceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surfrizu,n7qt h2+ ace will the inqh7zr, +t u2acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times thml iu3vezo3( c u/.bj+e radius of Mars. The acceleration of gravity of the satellite, as.(ei3v m3uobcuzj+l / compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center,io+,:6kqcz6o c.x8wjr vmfj4o* oj 1u the acceleration of gravityqj+ki ou. * oj,o68rvmwx:ozf c64j1 c 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 of the Earth. The Earth has radius(ua)a 7.n.bk7od m qxv r. If the object is raised to a height of 3r above the Earth's surface, what .qu (7ok7mvb) nxaa.d is its weight?

  By how many newtons does the weight of a 1crpmq 8okj1p3 0q om3+x39 neg00-kg person change when he goes from sea level to an altikng18q 9pmp33+x30qoo rjem ctude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. ekyg: tuccq 9-rz6w4*A satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satelliyrgk ew4q*c-c utz: 96te's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its raduj8cf 3 q/a/vaius. If a jar of peanut butter weighs 12 N on the surface of8 /3cauv /jqaf the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, 6bhb dcvm3((zw 5,z1(mkyo 4 lk w3fxjEarth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The m5 lj(wz v3b3(6kc1( kzm w4dxybf,hoMoon 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. +/rx u df:n gwc4bm044k pgqs1
(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 th0 *w wdos86ljhe surface of the Earth). What is the speed of the satellite? (The mean radius of the Earwjs 6d8 o0wh*lth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just skims 7dbz)hr r/r9( bn v;wt9 zpwbo,bly *8the surface of the Earth). How long does it take to make one revolution around the Earth? (The bb y 7wh ,zpd)/brn;t(9v9wzobr8rl *mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km abr7 yx;y+79h8( -hwl uyvugkhbove the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean rad h; hwy(hb7y l8uv7krgux+-y9 ius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diametej o*ha:mugc m9lw826sr 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 :hhjfssf/ * k7a 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 ,doz y fht1st6 8oah il80-l4gnearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an of18,6 hz ht4og lts- dali08yorbit?

  The planet Jupiter ier7.mqlbck ig09q k lfag78*8s $7.78 \times 10^{11} \; m$ 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. Wzp0ulpq8 jqd1 4bk,rphkj .) (hat is the average distance from Jupiter to the Sun? (The distancehpr 8)4lp .(u,j 0kq1 zbqjpdk from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)