Is it possible for an ob8w.bybn o 7 t ap-es)m9m9c5pbject moving with a constant speed to accelerate? Explain.m-cb)y et.ansp 97wob59 mb8 p

  Consider a particle movii zw)*q 04zig5jqvni4 ng with constant speed such that its acceleration of constant magnitude is always perpendicular to its velocityzzv4iqj4igni 0qw*)5 .

  An object moves in a circular path at a constant spe30l +nf6vnlzbwn3m 5f:ko+p eed. Compare the direction of the object's velocity kep l6zflfmn3n5w+ 3b:o n0+vand acceleration vectors.

  When an object experiences uniform circular motion, the direction of the 7wqrk, x8yrnvpu*/*i acceleration ku/8*q *rxwny7, r pivis

  Consider a particle moving with constant spe5tp(y wn; z4uwed such that its acceleration of constant magnitude is always per(tz;u y45np wwpendicular to its velocity.

  What type of acceleration doesosom 89 2n)jwx4zhb)-rl3e n v an object moving with constant speed in a circular path experience?z-8vl o9jx omhsnr24 bn ))we3

  What force is needed to makeqt-: ) h.erchttl5zqvg*;jql m.c h;6 an object move in a circle?

  When an object experiences uniform circular mobloejc +g g j(51)la-ltion, the direction of the net force i el5b-a+goclgl) 1j( js

  A roller coaster car is on a track that forms a circular loop in the vertical ptcq* cexc g8u):.gme 2mkh9p p)gw-2elane. If the car is upw cex9ghe*me. c-p)tm2:qk cg 2g8)to just maintain contact with track at the top 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 tha t7my5khuo zf2(qp:, at forms a circular loop (radius = r) in t ht75:m2 a,uzkyq(opfhe 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-cick +owk )a jwpu 6 j37;mmd,.,kkbgl4dk2th x,rcular arc until it is going straight up. Just as the plane is at its lowest poin;jwwgtx4j.mhc o7kk )kp, m+ua,326ld,bk dkt, 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 radi9z.q +:fn+ l ir5b,oxymbqqr1 us $r$ 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 so( 4, yq.f)v.xregzgfrz()pepeed v. Then it goes around the same curve at half of the original speed. What is the centg)og, prf. f4y e)z (er(z.vxqripetal force on the 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 /ru*zbn:r +v vr k+wb2k,y n-tconstant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as itu++wnr:*kv-,bynrz / tbvk 2r 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 rcbqe;k.(+ p3hr5v4h 1hjma ka oad is frictionless due to ice, the car can still negotiate the curve if the horim; 4hv 3kpc jbk. +rahe51qha(zontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are bankey( tcg (e*p7zsd at the same angle, but one has twice the radius of the other. The safe(cy(z t*p 7egs 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 track is0bcc idt8 x:b, not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out of the turn. cx 0t:8bd,cbi Why do they do this?

  Is it possible for an object moving around a dy w3eo g dax92oo68/(/yyqhmcircular path to have both centripetal and tangent/mq8 6g /w(dx yyehdoy23oa9oial acceleration?

  The gravitational forc)a6i;hf*:mk-r n-xn ivcv5n ze between two objects is proportional to

  The gravitational force between twmm iq ,wdvebw -vi/lct-b sf 1h+8-;m8o objects is inversely proportional to

  Two objects attract each other gravitationally. Ifh,3m3f5wb acprr wa7. the distance between their centers is cut hfap b,. a37mwrc53 wrin half, the gravitational force

  Two objects, with masses bo -9gw+5ho 85imp iw4kw- 4hvqahvk*$m_{1}$ 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)7 t1kfky.ogd+tr )-usmy -gn $m_{1}$ 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 gravite(74 okw ( vp+:2glqvc6cwdiuation.

  Compared to its mass on the Earth, the mass of anb q;yr/ 21omo3wsy3jfv+ kp y; object on the Moon is

  The acceleration of gravity on the Moon2yuoe9:pd q,h is one-sixth what it is on Earth. An object of mqu,9o hd:pye2 ass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the roc dnouks (tg0,kxxq pz.rx127(ket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull ofkhgw4 ff(+lz9ag0 wsj,jh8- h Ea s,(hh 4fgl+0k8zw -gfjj9 wahrth's gravity?

  Suppose a satellite were orbitin nyuf o281ktl4g the Earth just above the surface. What is its 81ykln ot24ufcentripetal acceleration?

  A hypothetical planet has a mass of half that oo*; s1vzsm gmm93 dq.qf the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planetm*dg;q93 mzm1qss o.v in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity 9w8mz nz9 7dhqae wv;86;zy3bmip5g con 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 maz yd 639ehzi; z;w8c vp58mgn9bm7aqw ss compared to the Earth's?

  Two planets have the same surf)83eztn1 gy bc j3p5pcace gravity, but planet B has twice the radius of planet A. If planet A has t)znce33bp8 cpg1 jy5 mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has f h/e5(f r: nawf7rb0stwice the mass of planet A. If planet A has rahw n /(sea5rf0fr7:b fdius r, what is the radius of planet B?

  Consider a small satellite moving ixwqx8w(ym *izd 5z c/6n a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital ve8iyd6*cwxm/zq xw ( z5locity?

  Satellite A has twice tl g97b,jl3tsp g /+vbjhe mass of satellite B, and rotates in the same orbit. Compare the two satellitejsvjg3t/+ plbb9g ,l7's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compare ty fov rd q);l(jrp-9nc cs756ghe reading on theg-d )s5 rc 9jp7qf;r6(oncvyl scale to the person's true weight.

  Who was the first persoq: 7xpx0(, hw/hn keben to realize that the planets move in elliptical paths around t ,xw:bee0q7ph /nh xk(he Sun?

  The speed of Halley's Comet, whilqa xjx3n,ru.6 e traveling in its elliptical orbit around the Sunn 6qxaj.,x 3ur,

  Let the average orbital radius of a planet be R. Let the orbil .ae2a)l lw1ucc j6pfk59sz7tal period be T. What quantity is constant for all plaz27w j9 u.le)p5flcs1c l6a kanets orbiting the Sun?

  A planet is discovered to orbit around a star in the o7u1 hpoap5fz)x 4c0w galaxy Andromeda, 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 planet be,hou0 zp 7paxcf ow15)4 compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is t w5vqv, ) 3e)pzfdq)gdefined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance t3vdq))fw ev)gqz,5p from the Sun?

State Kepler's laws.xzoqgl sn:,q0+t4 v-r b9 cb:h

  List the four fundame+k l.ksf9w1qyntal forces in nature.

  An object moves with a constant speed of 30 m/xt 21wsmxm;/8 m*r8axi*fbp w s on a circular track of radius 150 m. What is the acceleration of the objsa2*/xf81;bw*mix w m rmxp t8ect?

  The maximum speed around a level curve is 30.0 km/h. Wh-teygc/ 1(r iwat is the maximum speed around a curve with twice the radius? (Assume all other facer/1(ig- wyc ttors remain unchanged.)

  What is the centripetal acceleratiop prre-o z9q3 u+0cua;n of a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike is mo0oacz9 +ep pru;q-3urving 8.0 m/s?

  A point on a wheel rozma/.,mo ,usrtating at 5.00 rev/s is located 0.200 m from the axis. What is thezo/.m,ramu, s centripetal acceleration?

  How many revolutions per minute must a cir. vwnl *ink1t,cular, rotating space station of radius. ilkw *tvn,1n 1000 m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. xldlfh )55aj34l7 j ss:iof 4b It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on t fsj7il4bjl5f3 )d las4hx:o5he motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whitmv xo9+4pov.e(u fp 7x3t*i rrled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed of m+ * v7 t.re3p(9 oti4xfuvoxpthe mass if the string is not to break?

  A stone, of mass m, ji,jp.;3dtz8 e kuc7zpur2z 0is attached to a strong string and whirled in a vertical circle of radius r. At the exact top p upzze37.z;ditk20rc jj,8 u 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 string and whirled ixqz4;etksa2o9kb lp /fz7; n0 n a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The stone's spe/p;xnq;9 bofazt27ksl zek4 0ed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when s/0, zhicvj v)pulling out of the dive. What )zv0v/s, c ihjis the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the c; lgc9e8*2f2czk zu hp*;t3vr sb q:cgenter of the loop is beneath him) of radius 3200 m. At the top 23hf:gbuv c*zts;rec28zq;9 k glp* c 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 about se.cazt-epao v:d t 0*s)ven times his weight. What is the minimum radius of curvature that a j 0) ev:aop*zsc.tt-daet 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-m radius hor+lciik5 q8uf1q j; p.e*hxt. nizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume th8jqh en tk+u*x.1f; i5.lqcipe same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 grga 5*)sg6*ch ftg2f cfm* zwed(,,c m with a speed of 20 m/s. The centripetal force provided by frs c5**ggf*ah6m,t,eg cw2c(z )rf fdg iction 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 ogk gxx87e v)se m9.0tkf 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to x) v8xeg.tg0k7esk9m make the turn?

  A car is moving with a constant speed v around a level curve. The co n:wjs1y t8bs.efficient of friction between the tires. :ws8tjyns1b 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 requioey9mh m4v 2e9red for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Igneo e9mv2 mh49yore friction.)

  A horizontal curve on a bobsled r22e l )mlzoq5eun 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 radr0op +nhjan4w/vlnm2d v43d:bn, a,s ius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankedj*gfskm 2mfk( e7 w6eq )6ibo1 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 ;.y zx5 shrn fsu+vy7*end of a string is revolving uniformly in a horizontal circle of r.xhz ;n*suf 7yr 5vsy+adius 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 caryd ow4ig,xh),+owmw(du4+bv accelerates at a uniform rate to a speed of 45 m/ (w 4+ dd+ ,)vh,4bwygmouiowxs 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 of a proton of mass ( /,v y0- )dyuavbslbj$1.67 \times 10^{-27} \; kg$ 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 wx8n pklc 279sa 70-kg person standing on the Earth, due to the Moon? Tn k82xslcw9p 7he 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 betweenkuls,c miu;b)us 0ep0dq/k,9 two masses is F. If the masses are moved to half of their initial distance, what is the gravitational attractive forcc ms/0d9 ib, k)u0qekupu;, lse?

  For a spacecraft going from the Earth toward the Sun, at what distance f()z e2wkxz1zz rom the Earth will the gravitational forces ( ke)1zzzw2zxdue 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 pah4 r c24g/wpis $7.4 \times 10^{22} \; kg$ 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 di2 l; 6bc54uhc or t)va3/b n61gpythbpstance above the Earth equal to the radius of the Earth. What is her acceleration due ;n6 gho2vuph4 byb3c c15/ atrb6tl p)to gravity?

  The radius of the Earth is R.zr- ta5ms4h2y At what distance above the Earth's surface will the a 5arzt4 2myhs-cceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles M:bwavbujnf(9cts2;+v p2u4 sars at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, ia:4b +v uu9fptn(c2svw2b j;ss

  At a distance of 140au*z(si xg5s)vst l3*00 km from some planet's center, the acceleration of gravity*lg(usxas siv53*)t z 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 Eavpzd/h0i9 f1 fvjy1y /gxld(6rth. The Earth has radius r. If the object/yyddv/( h90i6v jx pl1zg 1ff is raised to 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 change when he goes from y8vo ,l;ty dpzvf,z,/ sedpvfy8zt; ,l,y vz/,o a 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 ad o*bb1r. *3tceif7o at a point 3r above the Earth's surface. What is the satellite's weightbbrf3otcoe* 17 . ad*i?

  A spherically symmet;r z/wzwm1xpo f7zjai6;14nq ric 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 wq;7 /6;zro1 nzmiapfjzxw 1w4ould it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same lizsd :ncv5yf) .ne, with the Earth between the Moon and the Sun. The Moon has a mass sn:v.)fz cyd5 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 tr cuavs7;7q.xfz vf 5k4ansported 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 ciir b*t;u:zrf: rcular orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite?t;uz r*frb: i: (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Eartvqq qlpp/p: 9 x3:pfp*h (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mea3l pxppf:pvqqpq*/: 9n radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circropbjs0o b:(n2 9gm1 xular orbit 230 km above the surface of the Earth. It is observed to ha9j0n: bsmr x2b(go1p ove 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,hlxk-1z:b /tfxm6ot/ zx+z/ g has 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 orbit 20oykms,.d5s( uwtt+6, qtyh*x bced s 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 or-, jrp) uimkh0sxy)a 4bital 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 i0k apx,-usy)mr4h)j an orbit?

  The planet Jupiter isw+dl e /ga;(tz $7.78 \times 10^{11} \; m$ 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 y2+rc. w ux1lviears to orbit the Sun once. What is the average distance flv x.ri1c2wu+ rom Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)