Is it possible for an obj . xuf;ck,v2fxect moving with a constant speed to accelerate? Explainfxv k2,;cux. f.

  Consider a particle movip/h ky, /1c j3adhtixm)fmf :)ng with constant speed such that its acceleration of constant magnitude is always perpendicular to its velom),x) adj tyfcf1hkhp 3/ /i:mcity.

  An object moves in a circular path at a constant speeeew7l t63ws w7d. Compare the direction of the object's velow7376s lewet wcity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the xc3b20 5lajvqacceleration lj2v q305bx cais

  Consider a particle moving with constant speed s ,t9hhfqmd. y ozf7z 1.rw-e,fuch that its acceleration of conswez1f,.r.7q9 zh m toyd- ffh,tant magnitude is always perpendicular to its velocity.

  What type of accelerajjt /bfc4xk ws;61 chq l+9qm6tion does an object moving with constant speed in a circular path expercq 616;c+wlfs 4 bxjh/jq9 ktmience?

  What force is needed to md4nyy6xo/)b7q vic1y ake an object move in a circle?

  When an object experiences uniform circular motion, the direction of the net f ysz5zr3-l;ae ngs+m)orce i -;) ssmnr+ g3elayzz5s

  A roller coaster car is on a track that forms a cir eyp,(j9p 1xgocular 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 g(xeo ypjp9 ,1for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on ag1tdjxzsm m5o -t(n6w xoau5+x,l vi.y-/m2e 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 lomw 6yx5(mao-ozs.xttx dej5gl2m iuv+-1n/,op, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows +9zvfp ,vc ,:fms bax,a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the forvz fb+,x:c 9,f,pv smace 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 curv,d e(*8*yixn8vjsajxo c2 (oy e 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. Then iuy a0d xay8i:w,/*hz 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 second time, diy8,/azwh :ax iy0u*compared to the first time?

  A car goes around a czg,dd9;(/ko sg 5zk tspz7be2 urve of radius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. 2zodkk(bgz /9ts ;7,zs p5 ged 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 oy1- qm7+ocr5+r3fdor gk9 qmthe road is frictionless due to ice, ko+q- yr 3omg 5doc1fr7+qr9m 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 to

  Two horizontal curves on a bobsled run are banked at the same angle, but*.9 /tn-ot0ol )ayh2nurr.ba jej9c n 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 speed on the larger radiu 9h 0lo-jroetr/uc)nb*y.a .a92tnj ns curve?

  The banking angle in a turn on the Olympic bobsled track is not consta6;by z4vcpnfk s r/mu44x fn29nt, but increases upward from the horizontal. f2bcvx zk/4mupr6n4fs9;n 4 y 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 have both centrip k 8aet2js:/uspw 3:owetal and tangswt2paeo8 3 /:wk: sujential acceleration?

  The gravitational force between 7woo *ntn+ as1c3up2txkus,2q, 4by9s. y cdktwo objects is proportional to

  The gravitational force between twovgn,,39b vb 0jfbiwa 5 objects is inversely proportional to

  Two objects attract each other gravitationally. If the distancen(q csohkn4 i704+gxt between their centers is cut gic 0(ton nqk74 hsx+4in half, the gravitational force

  Two objects, with masj nw y*3c-u6fo ;katn-z -xi0 jd6/qusses $m_{1}$ 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 ma pp1dea2 k/6zlsses $m_{1}$ 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 oako d57zk79; mnuka/ k2cip2 x 57pmtbf universal gravitation.

  Compared to its mass on the Earth, the mass of an object 9t1vzn9yb e ef0dkt82on the Moon is

  The acceleration of gx 8avhi l)trzh9r o:10ravity on the Moon is one-sixth what it is on Earth. An object of masst8r0v :x)hai lr19o hz
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the re jbo,60 630ttaxh watocket's weight

  A spaceship is traveling to the 9y b:;: jb8tjcnee7uuv4 v5ye Moon. At what point is it beyond the pull of Earth's grav ybv9u:5ctebe8 y; ue4:vn7jjity?

  Suppose a satellite were orbiting thg p41elh6g,/7hemfq le Earth just above the surface. What is its centripetal accele,6q lmhh glepf741/geration?

  A hypothetical planet has a mass of half that of the Earth and a rawi+( cxdbqiqoy0a7zx ** e62 a2+bpzodius of twice that of the Earth. What is the acceleration due to gravity on the planet in t2x( i wa exi*o*60 qaz2bq+yp7d+co zberms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on t+:5: pymfaw hfvwws419vetn2 he Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourte4f1ywvmsw2:h fp+5 : 9at vwnh that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surfaces gpu1mo 7xr*9b,bgn. gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of plane*ob7 rmg ,p. 1ubxs9ngt B?

  Two planets have the 1vn hqo;luj321aem ; e6pmqw :same surface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the r6 v wm;q 1ujeoma;13hplqe2:n adius of planet B?

  Consider a small satellite moving in a - o+kk. osu)blcircular orbit (radius r) about a spherical planet (mass b )kulos.+ko-M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice th 6i3 frvafytc):9/of5u vasf9e mass of satellite B, and rotates in the same orbit. Compare f3t:5vs/uf6)a9yc fvia9of rthe two satellite's speeds.

  A person is standing on a scale in an elevf lqujp-v0n1 9lqe.t+t8hap, ator accelerating downward. Compare the reading on the scale08jt+l1uq-tpln p,q vh9f .ae to the person's true weight.

  Who was the first person to realize that the planets move in ax*tbj ; oq3yz f,p4ru.- +bmzelliptical paths around 3bz.utzf4jyqr*; bpmoax +, -the Sun?

  The speed of Halley's Comet, while traveling in its elliptical ordvh+e +-+oqk ny qrsgpsmvu+ /ud,64 +bit around the Srdo +nmg u +-pkusy6eqqhv+4sv,++ /dun,

  Let the average orbital rad0ugw2jw. 1u caius of a planet be R. Let the orbital period be T. What quantity is constant for all planets orbiting .cw2 0jg1uauwthe Sun?

  A planet is discovered to orbit around a star in the galaxy Andromedr751wrz/a bhr a, with the same orbital 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 a1w r/h5br r7zplanet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sh2d z3 3gps*3yzhy3y fun is defined as one "astronomical unit" (AU). g23dsfhz3*yyz3h3 py 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. 2 q 0 ad2u0geph6ct2k80ferij

  List the four fundamental forces in nh9*tfw 0y0 n9fsi.plwh0b igu ) xuy*4ature.

  An object moves with a constant speed of 30 m/s on a circular tracksvwz u .6.oi2z of radius 150 m.osz.v zw26iu. What is the acceleration of the object?

  The maximum speed around a level if .kg+-o2f+f gpji 0ecurve is 30.0 km/h. What is the maximum speed around a curve with twicje+0gf.ik - f2gf+i ope the radius? (Assume all other factors remain unchanged.)

  What is the centripetal c8we )hm .q :04n/l p.ngkd,t-e ujyegacceleration of a point on the perimeter of a bicycle wheel of diameter 70 cm when thc /egjen8tq-e.wy4p, k0)nugm .hld: e bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis. Whacujsa41 . 6:hmbf df.st is the centripet6shfua:jm4.b.s fc1 d al acceleration?

  How many revolutions per minute must a circular, rotating space sjp*zikp76 sp *tation of radius 1000pzs*pkj i7p6 * m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass offr 4z*w8 lhnv+ 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on +4h*lr 8nvfzwthe motorcycle?

  A 0.50-kg mass is attached to the xpus):c3koxis1 2z9qend 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 if the string is not to bizp:k1sc9 x usx2q3o)reak?

  A stone, of mass m, is attached tq tjvs w*q*n-j81vy mj 4gw8j6o a strong string and whirled in a vertical circle *j8v*m w86g4v yj wqtsj-qnj 1of 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 this point is given by

  A stone, of mass m, is attached to a strong stringe fwk/7ysukif * i;st(- jgz 6-)xbza9 and whirled in a vertical circle of radius r. At the exact -ifwuzj9t6/*7zsk(y; a x -)keigs bf bottom 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 oc4juwt/q )6qpkcvqqz *+1 j-t ye/d;mf 4g when pulling out of the dive. What is the radius of curvature *dmtv/qje-/c14 j+qzqpw 6 y ;quckt)of the loop in which the plane is flying?

  A pilot makes an outside verticalar w k*lhx3;0i loop (in which the center of the loop is beneath k0 hwra;3*xilhim) of radius 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 can stand is abo9hg 1b7 m3u vb)3,b w,huovnyjut seven times his weight. What is the minimum ra ubm) bbwh7,3u1h,3yj9gn v ovdius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-f e l-o)c)5z9y6j stvnm radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curvee noc v9)lj-ty)6fzs5 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 alt5r4v sr 7l/dgivu2, speed of 20 m/s. The centripetal force provided by fr,2vlgs5l47 ti /rrvdu iction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve j;nw ns- 63japp2 ,vtkof radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road fvp;nj 3 w6pjsan-t2k,or the car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefd.k dzeoc*** mficient of friction between the tires and the road is 0.40. Wcod*.k*m*e z dhat is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an v xc7gxuy66u 2d-f9d6mf jhl0 Olympic bobsled to negotiate a 100-m radius turn at 35 9f dv02x6-fu6gm6c hjd7yx lu m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is .zr9o fa.aprqcsox s(7dt/ 8*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 rady )h5hfxc(b+dhzp yh: )1)t kflp 6:qkius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m asa 1 *q(u5rmd dzhx96is 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 revolving uniformly in a horizon0ji6zo5n5ofdc+ fy1f k3, kbatal circle+5kfnozd6acif ,o b5fj3 k01 y of 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 uniff rv)ml/dzc:c 4 5wave+ii7- morm rate to a speed of 45 m/s in 15 s, moving on a cirv/ 7zmm-cl d e ):+avcir4f5wicular 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 of a protonwck+ve ( eve7rz,2, cp 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 peranhx3 k(u u3n+q(wnr+son standing on the Earth, due to the Moonu w3nk xn(ua(3q++rhn ? 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 betwlfp8it/ktwr*6 i x)s :,yb pv(een two masses is F. If the masses are moved to half of their ik( 86/i, t vly*p)xtbrwf:spinitial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what ds( dx3c ..o o4r-t*e jlk.ccfristance from the Earth wic j dscrr. xc-3t(.oe.4fkl*oll 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 Moon isrfr 0,2j5uekyh, b9crsu2dxy* txa 7gqx*(0w $7.4 \times 10^{22} \; kg$ 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 aia1c-xa -o- vs k+qiwq57 ly1u distance above the Earth equal to the radius of the Earth. What is her a-iyxoq+71- ql ivawsu-15akccceleration due to gravity?

  The radius of the Earth is R. At what distance above the- 4 8 imujplxs9*k p7wa*fn,t ,kak1vd Earth's surface will the acceleration of gravity,u8kkxw*7j,p*-k t pld1 saifn 4va9m be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surf ,hb;p(nvsfv0 myzxz f. o.qzv+78wu3ace equal to 3 times the radius of Mars. The acceleratiozvbzy hz.,0qp f7ow mf;uv(x 83 .snv+n 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 .8kfnj ii1z()o v*xkml(tknjm26m)m planet's center, the acceleration of gravitylx8nm.i2nfm j)z1()jk(*m 6t ikk ovm 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 radinb6rzkftq ia89x5 u- 2us r. If the object is raised to a height of 3r above the E i8x9zfrt2 b-a6q5kunarth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change mu9 lh. 8o*egglwki:8m 5s(hh when he goes from soheghiu5(hl l m9: *kw8.8m gsea level to an altitude of 5000 m? (The mean 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 3r above i bb ychv 1);)evz-uk2the Earth's surface. What is the satellite's w k1b;-zbivyvc )hu )2eeight?

  A spherically symmetajgu i,: ,rw gjk)-;oeric planet has four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on ), ,- o g:eij;uwrkgjathe surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse; 1.aoddkvyxpraq 47(5 yliing80x e;, the Moon, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon l7dain d1;k o;0yra.5qi x pygvx84e(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 th8 du: q nxi4k2m0tec,ee 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 orbirn da-d+*x ve6t about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satel- dn xr*d6e+avlite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit cj)fridck2,df il, j24zqh/) about the Earth (i.e., it just skims the surface of the Earth). How long does it take tkfc2idfi ) h2r 4j)dc/zl ,,qjo make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circulcc0+b g mqwri()w2a m5ar orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is thec2bi wm0 wqr(m5 cga)+ mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an6:o6i *ehc twv 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 orbits4wegj l ran58u/7d8uq 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 A has orbital 1yamj 2)46m wgnuo 2pxradius 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 orbitm6 )4 gpom 2ja1ywxnu2?

  The planet Jupiter i ya9-lzo cppqt6tp2 05s $7.78 \times 10^{11} \; m$ 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 thj;65rta:eapd1 w:aqr e average distance p16rrajt ;a a5wqed::from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)