Is it possible for an object moving with a constant speed to aci70n .53adf rzvfryru3,1yyj zn+ v( ccelerate? Explainci7zf0 r+.f ynv5y uzdj,n3 vyra3r(1.

  Consider a particle moving with constant speed such thjziylid43 )eyt ighde501f+-at its acceleration of constant magnitude is always perpjd yygted 3i1e0h+ii4-5zfl)endicular to its velocity.

  An object moves in a circular path at a constant speed. Co gfmm * 7ec52th;dxu d:iex7f;mpare the direction of the object's velocity and accelerationf7;ci2mf 57: eugthm;d xe*xd vectors.

  When an object experiences uniform circular motion, the direction of the acce7ic 9w7d lubn:lerabicd 7u7:9wnl tion is

  Consider a particle movin-u0wdq;h49, ruxq x gbe *rva:g with constant speed such that its acceleration of constant magnitude is always perp 4u -*rr;0dbvgax qq x9h:,uewendicular to its velocity.

  What type of acceleration does an obje7vssi4ie ty yc3+i*k7 ct moving with constant speed in a circular path t*ek7 s4svyc3iii+y 7experience?

  What force is needed to m8qxtfzk g: u9.wkg-7xake an object move in a circle?

  When an object experiences uniform circular motion, the direction of the net fdsiv9 i::3vzzy1o (b oorc 1b(zyv:3zi9 sv :odoie is

  A roller coaster car is on a track that formscw5w6 .rw e3gd .p)pep a circular loop in the vertical plane. If the car is to just maintain contact with track at pw 3r.wgeew.p6p d)5c 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 that mmbst 8.vosa.)5ml ,mforms 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 loop, what is m m5olsa)m..smt,8 vb the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a ses gt (tc0/;3i4ijo psnmi-circular arc until it is going straight up. Just as the plane is at its i(o 3s4it n/0sc;tpj glowest 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 cur o.h(a/dry g) sbf: 2,pie,tq82lat gqve 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 it goes arouli wu ( h:iozw*m355zend the same curve at half of the original speed. What is the centripetal force on the car as it goes aroun lo(imwi3hwzz 5 :e*5ud the curve for the second time, compared to the first time?

  A car goes around a curve of radius r o:6futxw+lw+/ hft,l/ u y1aoat a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the cf1foauw /t+xo ,l: wlu+hy6t/ar 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 spe;1.a+:(sfmxkeqz dv6 kn9+y2my oztwed 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 rok(yn+9x zzd +.ws v1q;fkam6me:2toyad is equal in magnitude to

  Two horizontal curves on a bobsled run are be0a iv 1dnma(c8yxh n9d4 ir02anked 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 hd(v ac4dy8i2n100n9e rmi xacurve?

  The banking angle in a turn on the Olympic bobsled tr4- kqole 8j aeaej6):x(grh:nack is 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 q e4a 6eno j8 )eax:(r:hjg-lkturn. Why do they do this?

  Is it possible for an object moving aroi tp lv5-k.)h4( nghgkund a circular path to have both centripetal and tagk 5gip vl h.h-(nkt)4ngential acceleration?

  The gravitational force between two objects is 5nj( 7dxlrc5g proportional to

  The gravitational force between two objects +n)sl 8e6yor4.p/r scvah 2fhot+ 10u h crq5tis inversely proportional to

  Two objects attract each othx fr (2:ga 4qxip:ow;qer gravitationally. If the distance between their centers is cut in half, the gravitatioxpr2w;a(:iq:gq f ox 4nal force

  Two objects, with masbb,c; zx* 5 u/hg7ixrwses $m_{1}$ 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 mas(q;gawh 3bxxjw 9+yy 5ses $m_{1}$ 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 gravitat(6xj8 h,vsp0 y zgloo*ion.

  Compared to its mass on the Earth, the mass o )z6ls1e7h2 dwmm0fxm f an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth whn;lz uphhmj+u.l9e++ at it is on Earth. An object of .uhz p+jh;n l++em9ul mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the zo n:i9w4-y oerocket's weight

  A spaceship is traveling to the Mva 9)bd;.t)qoofe:vp2sx4r voon. At what point is it beyond the pull of Earth's grav fo.r;s:opax)qe2 )t 9 4dvbvvity?

  Suppose a satellite were o)z- r eyz42uvmrbiting the Earth just above the surface. What is its centripetal accelv zr-24 uyze)meration?

  A hypothetical planet has a mass of half thatb (d btd)p5rvm9nle*0 of the Earth and a radius of twice that omdbe)r*(dtlb 9 pvn05f the 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 gravity on the Moon is one-sixth .db ,p14-ulqcsgi/u x what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moonblu qg/dci-p1.ux ,s4 's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twilg/9uh( fb n90nbh7f ece the radius of planet 7 /0u9nbelfh9 hbgnf(A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B h.g8uw( 9vbw2 mqfvs 8ocwpecb )(6rj)as twice the mass of planet A. I ew)sb rw fj) w 8cp6.9(uov(2gvcqbm8f planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circu-ge47bfm -ival +n0fs uc, fd/lar orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital vell+uffe-f/ vc ,mdg ban 074i-socity?

  Satellite A has twice th3)0 jrne)-dmswjy f l-e mass of satellite B, and rotates in the same orbit. Compare the two satell0lmwj3 jnsr -e) -fdy)ite's speeds.

  A person is standing on a scale in an elevator accelerating downwarld 7jh+8+anbid. Compare the reading on tjia87bdl+n+ hhe scale to the person's true weight.

  Who was the first person to realize that the planets ohjju0ok)i vi- r.wrp60v,z+ 6qyc x9move in elliptical paths around the Sun? 6 vzro6i-u)ky,9c0qixo+ p jvwhjr.0

  The speed of Halley's Comet, while traveling in its elliptical d0cx2 kwc y )f0nxa,9xorbit around the a0cxc fn2xw0 ,)d kxy9Sun,

  Let the average orbital radius of a planet be R. Let the orbital period be T. 8 kmfsmfjv8 ob5u/-y3 What quantity is constant for all planets orb/sk88 3yfm umjb5f o-viting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andr /5xtzc7 e3hfjomeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of our Sun, what3z57/ ejx fcth 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 onyuv dl (10:f, dju9zkse "astronomical unit"d19zd( sfujuy kv:0 l, (AU). 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. ydz9 f9d,juekuvz4*e 6-qu-3g p*fpp

  List the four fundamenta89e qk 3l. x 4.goypakgcc7m;ql forces in nature.

  An object moves with a constant speed of 30 m/s on a dfu . *4 3zn)rjhzvfr71lhvw,circular track of radius 150 m. Whf j7f, hrw v1 n3uz4)vlrdz.*hat is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the m/ (k o*7/j tnnvcni7dd;tvnj9aximum speed aid*;tk(/no7jv9t/n n ncj7v d round a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimetbau+zolxzj95,n k-*m er of a bicycle wheel of diameter 70 cm when the -zauz5m+ kojb*x ln 9,bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locirbm 81y , c,sf4v0lncated 0.200 m from the axis. Whaty01 vf,m4csicl,bn8 r is the centripetal acceleration?

  How many revolutions per minute must a circular, rotating space stationxn 1evjhkia6 69ffixb20 , y,v of radius 1000 m ra9 ef6v6h x,k1f0 y,vn2bx iijotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kglk o);b 044/eatu g2buibnw:gy (nh)r . It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal forc: 2o0ngrtguy4lhe/;b (w) i b ank)u4be on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-mafg/(bg7/9m 5cju ger string. The system is whirled in a horizontal circular path. If the maximum tension that the string cafgrgecb(g u /9 5jam7/n withstand is 350 N. What is the maximum speed of the mass if the string is not to break?

  A stone, of mass m, is8w ;git).yg 8 /ytrbqc attached to a strong string and whirled in a vertical circle of radius r. At tt) y8.qgiycgb;rwt 8 /he 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 string and whirled in6dbe+-5xk zzx 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 speed at this point+e kx6zx5d-zb is given by

  A jet plane flying 600 m/s experie agamg)z5-ph-z- 38rgir( jpwnces an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flyiniga gzg 8)5 rajhpzp-(mw--3rg?

  A pilot makes an outside vertiwpy27p 469nt 2vtk;e mcvhqq7cal loop (in which the center of the loop is beneath him) of radius 3200;w7tc 24pe7npkmqvhq 2 9vt6y 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 sevenochud* 1 ax8/ueq7 h l rs3j(-mj,a1jc times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate cu8j eosh1udrm(7jcq3*,-/ x1a l ajhat a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius hori :ve)z/1f 5us,ohc afhzontal 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 sh ,ouve/azhc) :f51f each road surface.)

  A car is negotiating a flat curve of radius 50 m g,vh gg)ke 8+aw*rhs* with a speed of 20 m/s. The centripetal force providvgse g+)hk wa gh*,*r8ed 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 /ig,5ln( m5-yv r*z.u be2tl*ucefvo m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the rr/v-l5fevi. egy l ,2zc*ntmo*(uub5oad for the car to make the turn?

  A car is moving with a constant speed v around 3 oj7yopj24 jja level curve. The coefficient of friction between the tires and the pjo jy4jo2 73jroad 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 tbe1n93mg j6p1 mp igs9o negotiate a 100-m1 91m9 j nmp3pg6beigs radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled ruwetc xt.+rht31k3ur p7bf) t/n 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 100 m, bankeg,-s :jhfx2fx d at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at20 tds1j ueqsya- n8+c $45^{\circ}$. 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 unifba/o0oo8b 6sf+-uiz y ormly in a horizontal circle of radiszo ofb-/0byo6u 8ia+ 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 area, a race car accelerates at a uniform rv-,hg: bc7h oaate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in nugo7chbh- : ,vamerical 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 consiw0vxur2) pah .n(9 oqxsts 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 standingw.m.ec.j*fir3 3vl wer+w rb : on the Earth, due to the Moon? The mass crwe3i +fr:erb mwwjl*.v3..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 between two masses is F. If the masses are + iw9rdviw4+ 80gj1 sl+fxdjxmoved 9ri xi f++84g dls0 wv1djxw+jto half of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at wn/p: 8vi a1:rf(/(;xnex-mvh pu;hp nquml b/hat distance from the Earth will the gravitational forces due t8h x:nnr;pp q/iml(ua;: -xebunv f/1h v(mp/o 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 Moon3 dpx5-p,t fgf 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 "space3p/ il auek.cvckviude9 l,q/ eo-. (--walk" at a distance above the Earth equal to the radius c3ie-l.,.(o/eevcv9/k p akudlu-iq of the Earth. What is her acceleration due to gravity?

  The radius of the Earth ix4l-) b:hg gezs R. At what distance above the Earth's surface will the accl4zgb he-xg:)eleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times r9na oi25 k;withe radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of 2r 95onak ;iiwMars, is

  At a distance of 14000 km from some planet's center, the accezr.s l /,* hcppue-n(xleration of gravitypurp ,xlhcs/ -.*en (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 Earth. The Earth has radius6w kyn2xus 19fxtlo5bi:m 0u3 r. If the object is raised to a he936i unxm1ut olkx:y ws502fbight of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person chan7hzs-pi(,ag fw p+l*lge when he goes from g(7i lhp,+ lawfz*sp- sea 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 iyn ;cn*c-o7nj s at a point 3r above the Earth's surface. What is the satellite's j 7co*ny n;c-nweight?

  A spherically symmetric planet has four times the Earth's mass and yf1o1td(b mj9twice its radius. If a jar oy mt(fod 9b11jf peanut butter weighs 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 k qk g.q057rqz(sd.d yall lie on the same line, with the Earth betweey5 kdsqk7q. z0qd.rg(n the Moon 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 is transporvt1cya p)q+g(ted 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 the Earth (i.e., it just skims tx mhi) 0j:1wzxhe surface of the Earth). What is the speed of the satellite? (The mean radius o0jhi )1 w:mxxzf the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular ory:bv1xjc4wd. gp./ wubit about the Earth (i.e., it just skims the surface of thecwy.gvb/1 u4: pw. xdj Earth). How long does it take to make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 1t8xq-i zk bc9230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius x c1b-qtk89i zof the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an or-8: pinpevd0i fp i/y,bital 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 planet with a radius ofuoco x(0uu4n.;ftq8 a $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a planet in38 qkil.adw1yvl *k5k nearly circular orbits. Moon A has orbital radius r, and moon Bd 5.8kkv3i l*yqkalw1 has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter if pg51z e* b-ynpgh9m5s $7.78 \times 10^{11} \; m$ 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 thz- 8 wcqez w,a-in06oye Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth to the Soczeay0zw ,nw 68qi--un is $1.5 \times 10^{11} \; m$.)