Is it possible for an object moving with a constant speed to accelerate? Explaij p8z.lwn/l z+u-f/r kn.z-w+pklj/l8rz. u/f n

  Consider a particle moving with constant speed such that its accelerationvok ykk+1,f) o);dq 9va*s tnznb/gt. of constant magnikaf 9d/)b t)qvoo 1y+ksn zgt;.,*nk vtude is always perpendicular to its velocity.

  An object moves in a circular path at a constant spekxx6vrplp- ft g-+ 1n)ed. Compare the direction of the object's veloc-t- +pkxn6v)rl1pfx gity and acceleration vectors.

  When an object experiences uniform circular motion, the dirn2mda u*7hh64r8 aje n.xqk6 kection of the accelerkurena8d 4mqx n6 . jhha276k*ation is

  Consider a particle moving with constant speed such that its ;kw2 -. jtyaao9qtejsg ; t2b8xc8 4eiacceleration of constatik2 j9;ewsc 8axoa8e ;bt.ygj4q- 2tnt magnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with constant sjb:w e0c.;r dzv+c bq1peed in a circular path expevqcw jb.;+:b0z erd1crience?

  What force is needed to make an objeky ,u gksmv8/8y *w3ukg1uc *.u gt.ccr0 b;hcct move in a circle?

  When an object experiences uniform circular motist /ekn,a e0ii5yy g*8-kzja; on, the direction of the net force isi /k y;zyk*a 8iaetn05-, jges

  A roller coaster car is on a track that forms a circular loop inj )6gcb,p2xx g 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 centx2g,gpb)6 xjcripetal acceleration at this point?

  A roller coaster car ( 96: h4hjqpun1l wyi7zmass = 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 ath h6yniz4uq:917jp wl the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows o vrd+/0gsk5qvy rfz r e )phmr/(2.o,a semi-circular arc until it is going st +krqv rsv/,0( 2o5 fzrpy.odr/mh)egraight 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 radiuh -viv3:0fd of w:*phps $r$ 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 spvx (,x0j :tt1h fs2regjhlo--gkp 05peed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on thehf h gv2sejg0p5k 1(-t:xl0jrtxo-p, 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 constant speed v. Then it gog9 u,;:g m3tm9lk rybjlr1hz7es around a curve of radius3b;mrkr7g z9:l 1lgy,hum9jt 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 +cfmno/q -)reea9;a u 0b vl5wa banked curve 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 force on the car from the road is equal in magnitu+- lwc/b o;0earfu ne q95mv)ade to

  Two horizontal curves on a bobsled run are banked at the same angle, bunop bwbew-cko,8l(w(l.1(c kt one has twice the radius of ce.oblw,w(1(bkoc8-nk (pw l 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 the Olympic bobsled tra; ankc kg.nq(v 85o5yjxbc5(mck is not constant, but increases upward from the horx 5km.nq;5(5aco k8 (ycvjn bgizontal. 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 objerxhr+dxuxdc;13zrtt)+m)1 72 y di:t ax4pqd ct moving around a circular path to have both centripetal and t+d7x c2d 3x1q4 mr xdhy;upria)zrt+d:t 1xt)angential acceleration?

  The gravitational force between two objects is proportionwu.lptj9e(;e l po-g7j.d( sgal to

  The gravitational force between two objects is inverselff( 9qajzx vvmxmu8dl( 6e;igh(p+ 7*y proportional to

  Two objects attract z jqk vdzsd8n:+ivb z+-+5zfpgi04;meach other gravitationally. If the distance between their centers is cut in halfvz zdsd4+ ;+jk v+bpni g50z :zmq8i-f, the gravitational force

  Two objects, with masse3m 5tkzcu6av -s $m_{1}$ 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 yha; )z pl xx9(h1u0nj$m_{1}$ 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 gravitationkajx22bj6zctq6xg z 6zt47t . .

  Compared to its mass on the Earth, the mass of an object on th3vqnf4w2e3ivj g t*e(e Moon is

  The acceleration of gravity on the Moon is one-sixth what it i)zkortg,z0/e s on Earth. An object ofkz),o zre g0t/ 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 wei*nmi :;et7i(sof fj a-ppc3z2ght

  A spaceship is traveling to the Moon. At what point is it beyond the pull d60;h vi:hj.2elw2e+a,rhy c yv (ddi of Earth's gh; 0iaeddhv w+v:d(2 e.2 j6l,y yhrciravity?

  Suppose a satellite were orbitx ;2k0sfo3lmhing the Earth just above the surface. What is its c3f; ks h2oxl0mentripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and ap 3fm4j+ w l)ry uhe;4ew1,yfw radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the + f)rlw1f43, 4mewj w h;yupyeacceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what im1dd*6b +fu iawtp1 /vt is on Earth. The radius of the Moon is one-fourth that of the Earth. What isw6vdudt1+*bi/map1f the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B hasld96 ..nuce hn twice the radius of planet A. If planet A has mass m, what is the mass of planetdu .leh6 .9cnn B?

  Two planets have the same surface gravity, but planet B hai*cgx9o -ui(u(xn1 sy s twice the mass of planet A. If planet A has radius r, what is the radius oyi*isg(u(9 x 1c- uonxf planet B?

  Consider a small satellite moving in a circular orbit (radiuo6 xk,g)rnf)+br. 3 ,n (at03uctlkyu4gse hhs r) about a sphericnt 0)x43 cgyg.3 nf kkuru) ae+lohb,ts,6(rhal planet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the rh0hz(iqz;wdja7. tu9:(wm m same orbit. Compare the two satellite's speedsw qa jzdhuih0((zr:mm9.7t ; w.

  A person is standing on a scale in an elevator accelerating downwardz6t bud:70zwu. Compare the reading on the scale to the person's6wtduz: ubz07 true weight.

  Who was the first person to realize that the planets move in elliptical patns4w.3 t 2rmpehs ar.m2ep4n 3r stwound the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit aroun jlb19x*ff h0y1ox(f km3pi-fd the 9(h- fkf*pm0 1lfxxoy13ijfbSun,

  Let the average orbital radius of a planet be R. Leteabtmpc +v(qk8db .h.lk s*kh v )34h. the orbital period be T. What quantity is constant+4acd3hk)8keml tqs *. (.k.h hbvpvb for all planets orbiting the Sun?

  A planet is discovered to oruud )tj,vv8.ubit around a star in the galaxy Andromeda, with the same orbit, 8tuv j.uvd)ual diameter as the Earth 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 defined as one "astronomicjog*u;q81 ndp al unit" (AU). An asteroid orbits t *dop81;gn uqjhe Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.gjck; g ep:d 6io)ck36

  List the four fundamental forces i3 c0+o(zohe-)exmc gym9 7n jm*r;vdq n nature.

  An object moves with a constant speed of 6i, m+bc3 p,kgd q(fix30 m/s on a circular track of radius 150 m. What is the acc6i,p3bx+ ,m cdqi(fkg eleration of the object?

  The maximum speed arounl,sfofutouj(e :pl5uunfj,, .w66 8md a level curve is 30.0 km/h. What is the maximum speed around a curve with twice t(l:wms6j 6fo,uto , ufu. 8u,el5jfpnhe radius? (Assume all other factors remain unchanged.)

  What is the centripetal accelerati1xtvd 6r-y de5ctv35mo ,9bpd on of a point on the perimeter of a bicycle wheel of diameter 70 cm when the dpd9rdy1 v5- vmeox 3,5bct6tbike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is ip0d 40g (e3hjwpb2 culocated 0.200 m from the axis. What is the centripetal acceleration(db2 g0 picphu403wj e?

  How many revolutions per minute must a circular, rotatingx-,s5akmux(lyu2 i1b space station of radius ,k-us 251x alxmu i(yb1000 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 nfea4 gdrp3kf/h6b80 .7 m radius turn at 96.5 km/h. What is the fd48nak/3 ep6 f0ghbr centripetal force on the motorcycle?

  A 0.50-kg mass is attached to s71wr.hq./tv di n2jhthe end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that th vt2 hhdji7 rq.n1.s/we 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 attached to a strong stringbk2 3tcb(bcd r 1curl/d8k7 t+ and whirled in a vertical circle 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 thi1bc 7k 2rcdr/lu+cb8(ktt d3bs point is given by

  A stone, of mass m, is attached to a strong string and whirled in a versr 8 -+dipc4b v cp2ml8s/5ypntical circle of radius r. At the exact bottom oclry8 85 4-cpb /+2dpins svpmf 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 4ff cwuyk0 m(097nz3 vxg when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flyin ( xm00k79zfcywf3 vung?

  A pilot makes an outside vertical loop (in whsnp /pg; / m8c y1)el2h+jiyuiich 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 wih; /ml) +nu2gp8epys1y /j ciith only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times h570fr a yx oo,.hr9cxcm60w4y4 jbqxq is weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can toccjqy,xb 7 xyw4 04a5 r. r690fxmqoholerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal;rqhkl8r r /k xuw-t5;zsotp( o7 e8a4 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 otr(4xh/ p-w kt5 l7 ark;q88u;eoszrfriction 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. T ).r8ux 9iypjlhe centripetal force proviru9)ix.l 8yjp ded 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 zw fd3dv5)3h gu:8hfu7nu 6 *eh piwe5a 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 turn? zu nhwede53hg56h* fw pi )78f3v:uud

  A car is moving with a constabx9b y q/lr9mo avo32,nt speed v around a level curve. The coefficient of friction betweemlox/ bvoy b392 a,9qrn 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 anga9co8h7pyr9p-uu nk 7le is required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s w auko9ry778- ppcn 9uhithout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 03z(gmanshxyu.g d(/ 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 radiuf6rcy ku9 tr0;uo.p,yjc)o p p3 zv.0gi5eoo 3s 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bah 3dg18xkls e/nked 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 uniformly in a horizontal m+b6wxx5w:k)pe h7occircle of radiw ebomw7xhk:p) x56c+ us 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 are rf ahsqh4n hitn-3j.k9 z+frm5i:2 ;ta, a race car 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 numerical izq9h+h- t5 rimh4: f2.a;krtnjsnf 3 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 a proton of ol2afb*a )*4suth rs,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 perso)wymrs47a s0 en standing on the Earth, due to th s4e wa7ry)s0me 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 fp90stpyq ,9vi2q gzr qo1w0fs5ec.m w5ce;y*orce between two masses is F. If the masses are mo2wv5y1059pzq qw ,e0go*istcpy9 e msrfc .;q ved to half of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward thya2*ib l7 coj9e Sun, at what distance from the Earth will the gravitational forces du2ya*7cl9o b ije 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.dtwk/2n77wxo p:rm(:+ t ttwnhobf. $7.4 \times 10^{22} \; kg$ 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 f4q;d1q ouyrp k878qn mor a "space-walk" at a distance above the Earth equal to the radius of the mk qd1u;87qqp8yor n4 Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what dista 9yzvc;3f-)wcwwuy8eu7 ap8 jnce above the Earth's surface will the acceler7wu9yz8cwyc;jfuev-3pa8 w ) ation of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equap v/yulj8(rv2*cr: q*zjy o;zjn l 11ol to 3 times the radius of Mars. The ar;py1zy 2 (:*uojv l 8/lvn1j*rcqzjocceleration 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, the acceleration of gr)s+ksdj2hk9jqs 0 l0davity ids j2+lksqsj d0h)9k0s $32 \; m/s^2$. 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 Ear hp33i7 zz69is)jilkzth has radius r. If the object is raised to a height of 3r above the Earp sk)6z37ihz3ii z9jl th's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change8-ky-fzx;t) m 4t ,zrfdlcbch6 . +uel when he goes from sea level to an altitude of 5000 m? (The mean radiue.r-f -t,z ;)yl4uctx+6 dcbfzmhl8ks of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius rkx7+nljiym +*6rl a2z ahfv2- . A satellite of mass 100 kg is at a point 3r above the Earth's surface. What+xj*v2za6 hml lfay7 +kr-in2 is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice itz1bp ,nl0*jkos radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surfacp,o*kz1 b0j lne of this planet?

  During a lunar eclipse, the M1qb y,/6s/ zpx,eputroon, Earth, and Sun all lie on the same line, with the Earth between the Moonbp/u,r6yep / ts,1zxq 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 i1xwqy;6p u4g wlo(:eis 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 about th7w b6se4ou. oee Earth (i.e., it just skims the surface of the 7w6ebu .so oe4Earth). What is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low cizvayau :.m;9w vq -,e dx7vok:rcular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean ra:9.vd mqvveo- :uw a ;kzy7x,adius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of theec*x;0) uo d72i8bgoqa swyo2 Earth. It is observed to have a period of 89 min. What is theeoa8w;o ub7yd giox2c 20 sq*) mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbit8p+lus0os ag2y.zii 1 al 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 the plane*y.y*7abdarud(;lkn t 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 planet1u0vly.x e:sm in nearly circular orbits. Moon A has orbital radius r, and moon B has orbital ra l.veu10:ys xmdius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is/fbgcl/6wo .3th 1c ew $7.78 \times 10^{11} \; m$ 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.pzhi e9 nv5c+r,f99bp What is the average distancpfrc9,v 9h nz+pb9ei5e from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)