Is it possible for an object moving with a constant speed av 6vbkuz n*:7to accelerate? Explain. kunvb6z:va7*

  Consider a particle moving with constant speed such th pod4e9d vh7 .iedt1n:o.vzb6at its acceleration of constant magnitude is always perpendicular toboepdh. v7n4evtdd9oi 1: z.6 its velocity.

  An object moves in a circular path at a constant speed. Compare the1n5q2j b f7f,l xnx6e2 vygt z;8x/ouw direction of the object's velocity and acceleration vectorsby,5f7;nu22e1gq x xxj6 tfzv8no/lw.

  When an object experiences uniform circular mota-j, qt*s3) c/ih bw3ee3cgyfion, the direction of the acceleratio t qb/ciyhc ,3e w3ga3j*)e-fsn is

  Consider a particle moving with constant speed such that its ac8b2x5+r gmq i*a hn6(usxg-k uceleration of constant magnitude -xkhg8xb am5 rqni2uus6g*+( is always perpendicular to its velocity.

  What type of acceleration 9 aa+62bxun1ofivft /does an object moving with constant speed in a circular path experience2uan/f+9oaif 1 xvbt6 ?

  What force is needed to make an object moqx5 bphs ty b sqf-v1xje04o.1d1+si7ve in a circle?

  When an object experiences uniform circuls4o8s 4iz5x(veejagp/ v45.)tkne j7 .an vlsar motion, the direction of the net forcpev x)5 gvis j57l4.so an/4.avt sz8ej4(nk ee is

  A roller coaster car is on a trackm./;7kp)xfa 1 *uhu dvvhyg 5x that forms a circular loop in the vertical plane. If the car is to just maintain contact with track a apkv*7m ).x v/uuxydh5gh;f1t 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 t *vvbo(gjw6xhn,9 k +jrack that forms a circular loop (radius = r) in the vertical plane. If the car is jn* +okwhjvgb(v 6,x9to 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-circular arc un4ykkgjohni3) ppvj, :u)i y22til it is going straight up. Just as the plane is at its lowest point, the forceik goiny:j2yh2u ,)kjp v )3p4 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 radin+ b)i 3i3rqunus $r$ 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 arou09hjeewr / f;und the same curve at half of the original speed. What is the centripetal force on the car as it goes arou/j 9ree0hf;uw nd the curve for the second time, compared to the first time?

  A car goes around a curve of radius r at a constant spe);xf nqlk0 v50r0:l8ip,g4d wbzc kdhed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goel wgr,xihdnq b;fpdv40c 0k)klz8 0:5s 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 thek kw n)k3::dkbwm/ :qe road is frictionless due to ice, the car can mk/:3)e :k kw:kqnb wdstill 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 bo)dw(a)l 2piw b;(xthobsled 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 the run) for the smaller radius curve is v. What is the safe speed on the larger radius cua;(x) bi)w dplwt2h( orve?

  The banking angle in a turn on the Olympic bobslj.:.lvz h*txced track is not constant, but increases upward from the horizontal. Coming around a turn, the z :c.h*jtxv .lbobsled team will intentionally "climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an b2+r*aczlx t oo+z:gtc/(3 apobject moving around a circular path to have both centripetal andz *czt:o2gpr c( l/o x+bata+3 tangential acceleration?

  The gravitational force between two objects is pror wb7):l 3wy1due vt6 *6x6zyujm*onxportional to

  The gravitational force between two objects is inversely proport/9v wsj6xdz,me9 ai5gional to

  Two objects attract each other gravitationally. If the distance between 7j kf30;bvy k1y56p mys fl2/v*w rehctheir centers is cut in half, the gravitationy 2cy; 53 flmkrk0vfheb1sy/6 vjw7 p*al force

  Two objects, with mass*3o3qy j ;afhh w-*mlees $m_{1}$ 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 massex/r ia8h*ydc5a 4.tlt8e yw9h s $m_{1}$ 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 gravitak iz:n9re864 ja bqv-ution.

  Compared to its mass on the Earth, the mass of an p ;rpem0mtp5l(ajh .)object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what 0( do:f1,zn* j;vk jdheox nl8it is on Earth. An object o;jfx,v(nhekl d 0 o8*j1:nzodf mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, theayi;bn/h7d;v r/e 8tr rocket's weight

  A spaceship is traveling to the Moon. At what /ev 8i42wu t6ad15xt qlbzv4npoint is it beyond the pull of Earth's gra t1q4ndu6 awzl/t5veibv 4x82vity?

  Suppose a satellite were orbiting the Earth just above the surfhf xgd6iweth(7r,j 9+ace. What is its centiefrhdgx j 9(7, +6hwtripetal acceleration?

  A hypothetical planet hh qco it*kyj+/;61zov as a mass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, thvhcjz/qi*t y1oo6k+ ;e acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon ic18uc d7y4w ,xokcm016 :lxd t 1yczvds 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 :ct1vwx6u11y cc 04k8zxc oddmd7 yl,the Earth's?

  Two planets have the same surface gravity, but planet B has twice the radius of,x)d3lg8)lw mv7bsw.qfj 2d aw nw *7f planet A. If planet A has mass m, what id 2qv lwf,3 lmbgs* ax7.w7dnfww)) 8js the mass of planet B?

  Two planets have the same surface gravity, but planet B hafoyb vdfx-qf ;vm 3cemd*fk 7wy: ,g/3x(0 1ahs twice the mass of planet A. If planetb(cwof x*mvkgyd;h:0v/,ex1q3 mf f-7 d3afy A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a s)/h-zxhex - byb34oz fpherical planet (mass M). Which expression gives thi4 )z zb-3/hf b-hoxexys satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. zlze*y-*vwp7 y 3q; ce Compare the two satellite's ;z eq-vlw7**c3 zepyyspeeds.

  A person is standing on a scale y5l5 ,cuwc:n rts09je in an elevator accelerating downward. Compare the reading onycr 0l:wc tj5ns9,e 5u the scale to the person's true weight.

  Who was the first person to rea9 lut60 agxohe.pw6azpi-s 92lize that the planets move in elliptical paths aro6g- 9sho6t wea i zl09.ua2ppxund the Sun?

  The speed of Halley's Cot(: d3 tp9bdmg361a y(kuangrmet, while traveling in its elliptical orbit around the Su(3g:rtbk pt1dy6 u9dag(a mn3n,

  Let the average orbital radius of a planet be R. Let the orbginzj:v lqoqr6/ /n94t;ea s/ital period be T. What quantity is constant for all planetqtn:6 4j/o q aslgnv9 ri;//ezs orbiting the Sun?

  A planet is discovered to orbit around oup9,n 6qz xqztjhovy 3*+ o2*a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 timtou*onqhp z3 xo,q69vy j+z 2*es 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 Ear-:y1bzocd qn+th to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid'cqon +z:y db1-s average distance from the Sun?

State Kepler's laws., s/mra vbth mio(8z/5c6 epn*

  List the four fundamental w aj2g4o cqx3joyd:fni59nq3)c c-w9zn a2 m9forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radius 1qyrf54nm :4bp 50 m. What is f5 npy4 rmb:q4the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the mpocs5,r:t;c/zr nqo/ aximum speed around a curve with twice the radius? (Assume all to ;:rnr/s,5co q/zcpother factors remain unchanged.)

  What is the centripetal acceleration of a poz:vdm7; kuj:g)ga/ k kint on the perimeter of a bicycle wheel of diameter 7a gg)/kzkuj:7 km:;d v0 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.eonnj ( 7.hgyu t uh-x:q4ej1000 rev/s is located 0.200 m from the axis. What is the centripetal accelerati. uu n47 :ejxthhj0gneo(-1 yqon?

  How many revolutions per minute must a circular, rotating space sta10 by ylvo69ks1. jhahjk,e f9tion of radius 10vof hy.6 ksb1a,yh el109j9kj 00 m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a ma zaty4ls/ 5rsx7x3 y8qqwoe9ytym; 3,ss of 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the cen; 9 e3, sar zx4y8ot3 qy75yqlwtmxs/ytripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system isr c.gzuufks;* d8qmg2 -,p1sy*4srz e whirled in a horizontal circular path. If the maximum t ;zsszducgg r*,efk8m4.-yu 2*s1rpqension that the 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 string and whirledg( al dgn*wnq/ 9y5xp574 baje 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 this point idng agn9e5(7/ ypbwj 4qx5*al s given by

  A stone, of mass m, is (plp:o r 4lvy8g3 ,dg v3/wlel9n0toaattached to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the stro,l40/lpnw9 vopdv galtl( 8ry g33e :ing is 3 times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 60qzv*dm.vwa, x; 0dqkm/ ty .q, uc;4om0 m/s experiences an acceleration of 4g when pulling out of the dive. What is the radius of curv*u xcom. dkq4m vqq,tw.zm;/;a0vyd,ature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of ; ecuhye q rak2-5sj47the loop is beneath him) of radius 3e-er 2sq75 ucy;h4kja 200 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 about seven t cy/w *1jfw t*/ey/mkeimes 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 of 25wf1y*t /k* y/ce/mwej0 m/s?

  A car traveling 20 m/s rounds an 80th,ig t 5 w /;*)gafh,byk9cye-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a,bf eky5;, * / g9whhygati)ct second curve 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 a spe/8fr7j i thn9kjntk d+ g3+ iccx*x7v9ed of 20 m/s. The centripetal force provided by frictiont3n+gx/kftn dh997j rvi+k7ixc * cj8 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. Wz m4l7uew-s7twhc0 . ahat must be the minimum coe7w 0 s4lw-czt. hau7emfficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. The-tp)(0wsb lc , -q4bi)atoidi coefficient of friction between the tir4lb)-qi)dt s at0-pic, i wb(oes 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 n,dzyp/i c8d6megotiate a 100-m radius turn mypzi6, d8/dcat 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled r md8wnlw4qdc ;/r,u9fun 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 106c*n2 t pd+n*tp:unlb0 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked 0 u,alfzz 60gfat $45^{\circ}$. 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 ueyw;cpd3w * 29 x(1bpae fkcz75+nf wmniformly in a horizontal circlecn2p +e a37w w c5fkxd1w*;yzf(9bepm 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 accco (d* 1xz1fmdelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on 1c*1od (fzm xda 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 cos0- gk*y bw3 ip2xb4zdnsists 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 person standing on the Earth, ds nylth u+ k jw:zw4:q9i-s0j6ue to the Moon? The mashww ksq::slz0 j+in4j6-t9yu s 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 attract )eozyh;bko. .ive force between two masses is F. If the masses are moved to hal o);y..bezhk of of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth towar uh jojm+5:b:x zx4is8d the Sun, at what distance from the Earth will the zb x:4+jix5u h8:m ojsgravitational 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 - b+ax:lj9r6wgfo47cta4m m h* encr,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 u70dna31r pih* (isk pdistance above the Earth equal to ta* ihn3kr1(0uspi7 dp he radius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is g4)gc y req/0pR. At what distance above the Earth's surface will the acceleration of gravity be ryepgg0c4/ q)$4.9 \; m/s^2$?

  A satellite encircles Mars at a dis jmm8o f,1al4atance 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 surfj84 o,amam1 lface of Mars, is

  At a distance of 14000 km from some planet's couvjco1ve9ln/p /dca9 3 w0ape8u2 -fenter, the acceleration of gravitylvueo v uw pe2ap8oac/n 19jc/-f0d93 is $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432nzdm3/;h 1 rtb N on the surface of the Earth. The Earth has radius r. If the object is raised to a he/rmzdbh 1nt3; ight of 3r above the Earth's surface, what is its weight?

  By how many newtons 2qea/4ql ws9h does the weight of a 100-kg person change when he goes from sea level to an altitude ose9/4hqqawl 2 f 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 jw7z,ro s*y/59 ebnphis at a point 3r above the Earth's surface.ozryw /je*ns ,59 7hbp What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twq i+4drrtjp:7d.ngqsn /0zj 1ice its radius. If a jar of peanut butter wpn/g+sq0:z7j i r4.jt rdn1 dqeighs 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, Earth, and Sun all lie on the same li/, , fk6t4,l o jmtjk(8ojbzaqne, with the Earth between the Moon and the Sun. The Moon has b m6oklaj f/,(4qojj,tz,k8t 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 transportu7ec e x 0ovt/ dp+1xr(l2xo.ped 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 abou:82 v4w uh0nomqws7jmt the Earth (i.e., it just skims the surface of the Earth). Whammow7v 0wuqnh 24s8 :jt 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 circular orbit about the Eam73ryuis zgx9 74p n06nms :murth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean radius of the Earthr7m6 u4:nun03m9ims 7sg yzpx is $6.38 \times 10^{6} \; m$.)

  A satellite is in circularac )uyw2d-8iq 0ug -jg orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of t8uycg qa-d0i-) ju wg2he Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Juz f.)z;da;8sukg u,lm2;mt;hjku a w9 piter, 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 oxmgc1 st0-:n1v vzswp;* 3 bqwf Jupiter orbits 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 radius rn 6;i)gntv1ix +yynq 9, and moon B has orbital radiusnxiyi +;v)n tqy 961ng 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter irn lha75rmgj wfee 78 br79(y7s $7.78 \times 10^{11} \; m$ 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 oy4b/u -)2c6erv hnuw8v6np o unce. What is the average distance from Jupiter to the Sun? (The distance from the Earth to r)8ye/ho c6 uv2up- n6unbvw4 the Sun is $1.5 \times 10^{11} \; m$.)