Is it possible for an object moving with a constant speed to accelerate?jp4 s+i d m20uf2yqdo5 Explain.dqdop5 4ys0+ 2 uimfj2

  Consider a particle moving i,tp*klze ca)g6 k,(p7+yug nwith constant speed such that its acceleration of constant y p7t *kn+czu pag( ,,iek6gl)magnitude is always perpendicular to its velocity.

  An object moves in a circular path at f((ya 7eog 6c4und fy0a constant speed. Compare the direction of the object's velocity and accelerationngye0cfo( aufd476(y vectors.

  When an object experienceqi4 qo6r*e )gvm9v0su s uniform circular motion, the direction of the accelera0sgqvi 4vqeo* 9r6 m)ution is

  Consider a particle moving with constant speed such t stta; mx79l/oamv l+,hat its acceleration of constant maxma/s omat; vt,9l7+l gnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with constant speez lyfcsd4nozd4 8*lu750lu5z d in a circular py58zl4 n uo0*uz4sldzf7l d5c ath experience?

  What force is needed tgggd2p ) ur5jk+(ec4 bj5enr-o make an object move in a circle?

  When an object experiences uniform circular motion, thes v5fv0* 9ps1nm p*f zew))g,qs oh :r1sfh4bx direction of the net force isp 1e95q ,vgs fzs) )rvob4:h*m*f1xpwsfn 0hs

  A roller coaster car is on a track that forms a ckr**; kn1qmkse z;/kl s,dx./wd7ou g ircular loop in the vertical plane. If the car nksg;.o qkuswmre*kd7 xd*/1l/;z ,kis 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 (maxk,z b 32.ccoyss = M) is on a track that forms a circular loop (radius = r) in the vertical plane. If the car is to 2x 3co, k.byczjust 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 until it is g6 viq3upe6v6b cu qa+4oing straight up. Just as the plane iq q+ 3cvi pu6u64v6abes 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 radius i r:yn bykx4vht(,x6 0$r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve oblw. yhm0g-fp2 qg9ql 7v9v :qf radius r at a constant speed v. Then 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, compared to the first timeq9qp:- h0mvgb72l.f glq9ywv?

  A car goes around a curve of iszyp ,r)i xgrdppt9q*32ix7 sm :vyq.;jh9 +radius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, compared to the firstq7pgv q+)*:siz.p 2t9ix,pjs mhy3r d yxi r9;?

  A car of mass m goes around a banked curve of radh+bd5 5qjpcu 5ius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component5d cb55jhuq+ p 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 vfm* 9jn0(l pjone has twice the radius of the other. The safjfln( m*p0v j9e 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 thedoae5)tiw z -6gb-6qb Olympic bobsled track 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 turn. Why do they do ba d6-qibz6et 5wg-o)this?

  Is it possible for an object movie5+np 7ek qzhpd23o n3ng around a circular path to have both centripetal and tangentihnn5 3o7q32 depkz +epal acceleration?

  The gravitational force between two objen)04;u4 0 3hoxsv*gtcm 5rir so rn)iccts is proportional to

  The gravitational force between two objects is inversely proportional t, wmv7egqo e 3k*il;-7x*wturo

  Two objects attract each other gravit a74;h /pot6hvw b:eddationally. If the distance between their centers is cut in hd6hb:at4ph 7ve;d/wo alf, the gravitational force

  Two objects, with massw0cc-zlj* 9d ves $m_{1}$ 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 1 w8w+ak8jbblt96zm fy i9 mr.$m_{1}$ 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 univeuv4wgwk ,fn;t4p/: zersal gravitation.

  Compared to its mass on the Earth, the mass of an obje:*i8tibny4 tict on the Moon is

  The acceleration of gr)cc0mmtrw93x1 w ne5szu4l:1 r3x wck avity on the Moon is one-sixth what it is on Earth. An objewun :rc5x3 1 ec4zs0ctmmkw39lr x1)wct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, bm6)gajq6k :2a 0 .lh2vl dj5liw;h stuoy 6-nthe rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull of :dn *orggk.9 mzp/( (qg xx ibx/jmy/1Eart(bxgz ni.9qd kx m /p/g/j(ryg*x1m: oh's gravity?

  Suppose a satellite were orbiting the Earth just above the surface. What is iy o-m.l).- rz c8cwvsjr/(axhts centripetal acceleration?cyz).o-(wsc- jvm r l8.ar/xh

  A hypothetical planet has a mass of half that of the Earth and a radius of twi v b025pho1pibce that of the Earth. What is the accelerati5b iohb021pvpon due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the 1vb*b/8k eomxMoon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the vemx*1bbko/8 Moon's mass compared to the Earth's?

  Two planets have the same surface l / ems d;y.bvx59w4wd;lax;dgravity, but planet B has twice the radius of planet A. If planet A has mass m, whey; vd /4sxxd;l;b.ml d5 wa9wat is the mass of planet B?

  Two planets have the same surface gravity, s6k / asio2tjdte9o k *amel,; e1s0atm73b o.but planet B has twice the mass of planet A. If planet A has radius r, what is the90o6lk/ ;ki moj.a*tm3s se2be17ea os ta,dt radius of planet B?

  Consider a small satellitpw /qln ,jy24ge moving in a circular orbit (radius r) about a spherical pl/ 4y,pqw2 jlnganet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice tym3. s;y p*tb;l-jze ghe mass of satellite B, and rotates in the same orbit. Compare the two satellite's speedy.;s *3bp;yml jt -zegs.

  A person is standing on a scale in an elevator accelerating downward. Com(81 uidis:l 7lgynmdrh:l( r)pare the reading on the scale to the(r lmgnlus yd hii7l8d)( ::r1 person's true weight.

  Who was the first person t: )zj v6enx-tdo realize that the planets move in elliptical paths arx6e)jn-d zv :tound the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around thm,); : bnnqzyhe Suqbz )h;n,ynm: n,

  Let the average orbital radius of a planet be R. r4ea67ul ) u wa5r7vpbLet the orbital period be T. What quantity i)upal 4 ra7ubrwve756s constant for all planets orbiting the Sun?

  A planet is discovered to orbit aro wftvunl+7m2 8und a star in the galaxy Andromeda, with the same orbital diameter as the Earth fvunmt 8wl +27around 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 thepe8m1e +s riq/ Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the qpm /8+1eiersasteroid's average distance from the Sun?

State Kepler's laws.swlx ;i;z/i; r

  List the four fundamental 2hf uqvf1l/p;forces in nature.

  An object moves with a constant speed of c2hiu/mv,) ggi+i;zz cj /)hr 30 m/s on a circular track of radius 150 m. What g/ rccu)m;/zg vi ,hjhz2)i +iis the acceleration of the object?

  The maximum speed around a level curve is 30.0p 4 st//vo8kkj km/h. What is the maximum speed around a kt4 8ps/jo/ vkcurve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bit6 tfelhn a.5:cycle wheel of l6fa.ttnh5 :e diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00tnyc-aypqsn)d :5 . ,w rev/s is located 0.200 m from the axis. What is the cenynpqc: ,nya ).5d-ts wtripetal acceleration?

  How many revolutions per nzem43 ,jafhm(o)gf3minute must a circular, rotating space station of radius 1000 m rotate to produce an a4ejff () m ,33mohagnzrtificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m cdm cu5)1ly9fenx *9szn (,bnradius turn at 96.5 km/h. What is the centripe f*cuy99,1lnnzebcx5n)s ( dmtal force on the motorcycle?

  A 0.50-kg mass is attached to the en tkf9+z.k j;sj-dy5m6i w e)zbd 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 mje- +kz5z6ds ;i.tfjywb)9kmaximum speed of the mass if the string is not to break?

  A stone, of mass m, is af 1wd5z0ze(2(i*6 gho 7 sjmq4bz rlaittached to a strong string 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 wei07zs4* (2o qmiw jr51 bfza6edi (zghlght. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in (6bj xfdxb ngg-hi5;7 a vertical circle of radius r. At the exact bofb7jnix( -g5d xg6bh; ttom 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 9ua+ w*m, p1qicx6uq 47h+esb - qweyaexperiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the p mq 7*uwhqas c+y+qu6e ,9we4-xpbia1lane is flying?

  A pilot makes an outside vertical loop (in which the center o-5v b.5jozbjuf the loop is beneath him) of radius 3200 m. At the top of his bv5oz5j buj.-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 times his wein* 0iodo b1/742 bffein7yadight. What is the minimum radius of curvature that a jet plane's pilot, pullib0n2fya d eion71ifd7/i*4bong 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 horizontal curve with the tirekk 6 yna4a-o ;tz(pil3s on the verge of slip-6ly(zkk3o; 4 itpaan ping. 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 each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 *oj n 9ualrol ry81,b(m/s. The centripetal force provided by friction isl r1j*oo bl 8n,(9rauy $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 54,g cc( q2lvsl0 m at a speed of 14 m/s. What must be the minimum coefficient of friction betw,gsl2v (l4ccq een 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 coefficient ouwogh3hv.e qg: 8d 3mcc06k;sf friction between the tires and the road is 0.40. What is the minimum radius of the curve if mgg v3 63q;h8u cckdwe:s.0oh the car is to stay on the road?

  What minimum banking angle is required 4bam)j;b ahs5 mal2ar:a(d /em ,l,vlbjq:f8for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without:mm; h lbvad,af/qj(,eraa 8 52 sb4l)ba:jlm skidding? (Ignore friction.)

  A horizontal curve on a bobsledf 1m33xn q,1qt+jebsj run 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 mete /gu;+v odkbk8ec :0 u3za), banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankx7dg/ov kfii 1ma8g(;ed 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 :w9i fy6gd- 5kcw 4cmd;w -8rcq:eatbrevolving uniformly in a horizontal circle 9- t:ew4d:kqcbd8;cw ig5fc-ma w yr6 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 uniform rate ttbjxxh76 e,5k iy)y1moa e3- do a speed of 45 m/s in 15 s, moving on a circular track of radiu,h oyi k tbm1yxxe637) -ejd5as 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 cons61 h sor4)ls(( feevpa;ed/m tists 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 )y o4wq )pw 6r-do: z1g+qrc. rhfu0qfon a 70-kg person standing on the Earth, due to the Moon? The mash1fqodczuy g r fq)w4r.)r:0pow- +6 qs 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 thy1 - gu x)udy0(bnfio yd(nj)gcfo16-e masses are moved to half of their initial distance, what is the gravitationafn ofd)- gyunob(ug0i11yd6 xcj y)(-l attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distah10i7qs(g e-qzkw :b ince from the Earth will the graviq0k:i-qzew7hi b s(1 gtational 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 ik l kj7w xmb:(;dt68rus $7.4 \times 10^{22} \; kg$ 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 distangx( j,6mjz.1her;a y pce above the Earth equal to the radius of the Earth. What is her acceleration due to ;je h.rjy6(1xpg,azmgravity?

  The radius of the Earth is R. At who8wc5q;)v kc 0jj2hovat distance above the Earth's surface will the accelerationvo ;k jojc whv2)q05c8 of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a dis-hk yf:9jt on1tance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the saf1o: y9kht-jn tellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some p(mf y8e*l)j4 2vh sq(hw:qkrtlanet's center, the acceleration of gravity e(*hrvmsj ky qthl2f)( qw4: 8is $32 \; m/s^2$. 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)l a z/;rz/cay Earth. The Earth has radius r. If the object is rai)rz;z /aac y/lsed 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 kbsbttq(ltz8+n.s4 u 5sua1 3 person change when he goes from sea level to an altitunusutl3 b48ts+bzs(15a .tqk de 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 i g09sy x)gjs7sy ;ram6x4u0yp7n:ow 100 kg is at a point 3r above the Earth's surni os7myuy:0j g9xr;wag70)xy 4pss 6face. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice it;-7xk7lx d s)ai3 z6:o ukdo(6mfbjyls radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of thisz 7lu)mo6ixs jao(dkkfx7:d;l36 -by planet?

  During a lunar eclipse,k w+wx lgp cla0c35ozksj 02)) the Moon, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mklc a0l+go2s3kp ))ww0z5 jxcass 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 db;+epoytk7 l2 hlp6ui-+(gptransported 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., itp ib2qpd/ 3d2w just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of the Eb32 d/pi dqpw2arth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit z0/0q/ rk6epxzt b:ysabout 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 radius/b r0 :s x6ezq/0kyztp of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the sj82+- p.azycxry 1mu xurface of the Earth. It is observed to hav2 umr c+xzpyx-ajy 18.e 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 Ju 6mq5y m *9vz-zpthvr/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 of Jupiter orbits the planet with a radius 2dcto8)mx ldydfy5i /9w,fqi+ 6oy h).tz ,cyof $422 \times 10^{3} \; km$ 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 0ixfc8p2swy2 r, and moon B has orbital radius 4r. Moon A takes 20 days to comypsi82 c2x0wf plete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is -8sgezmt q 5qm;:ju d3$7.78 \times 10^{11} \; m$ 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 Jur1wr+y7ga ww3x kw .9epiter 12 years to orbit the Sun once. What is the average distance from Jupit3x+kywwrew.9ra1 w7ger to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)