Is it possible for an objectyd.0s;t0p4 4jmp sfal moving with a constant speed to accelerate? Explainj44ysfp;d.0s t l0pam.

  Consider a particle movinn+ os4awwnqt91;2w x ;n.n6oyjbv*o ug with constant speed such that its acceleration of constant magnitude is always perpendicular to o;b*1vu2a4+nwo9n so wj.y6 n; qnxw tits velocity.

  An object moves in a circular path at a constant speed. Comparetdosa9rry:9k v pial4p9- 5q0 the direction of the r-y9aal49dt9v p5 o i:0rqkpsobject's velocity and acceleration vectors.

  When an object experiences uniform circulass-* u9fd nioap0h0a8-q am w.r motion, the direction of the accelesa*0h-8i dn 9paomwu-s 0qaf.ration is

  Consider a particle moving with constant speed such that its fqe ffuox65zq +* w4;racceleration of constant magnitude is always perpendicular to f+w f6eu5q;*4q xofr zits velocity.

  What type of accelerv9*y ygzt+ ;loation does an object moving with constant speed in a circular path experience9v;lty +gz*yo?

  What force is needed to make an object move (gqc-,u( h sh+.fxoje u- 6cggin a circle?

  When an object experiera+ veyjez ,dkf849)hnces uniform circular motion, the direction of the net forcef84kerye+j, vz9 d)h a is

  A roller coaster car is on a5tu5ae/ 9 svzb track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, wa5 suebt z9/v5hat is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circ q4w:qc;kmp)l a;ib .vxi p1u/ular 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 the minimum value for cmx .lp)1p/ iqk;u:iqwb 4a;v its speed at that point?

  A pilot executes a vertical dive then follows a semi-xkmos /fh: nen2: ixt16eq56pcircular arc until it is going straight up. Just as /oh 6 i:xes1n6:ktnfe5 xq2pm the plane is 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 mal/5dt6nv7 sy yoj)l iph 3:8$r$ 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 3m jh+pm9i+ihzy,wys; qo ;q .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 the3 +;.qjoh m , zmswpqyy;9hii+ first time?

  A car goes around a curve of radius r at a vn66 2jksszv6constant speed v. Then it goes around a curve of radius 2 s2j6kvszn6 6vr at speed 2v. 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 ar )d yrf4*u0 ftq4xijtf*3 y;deound a banked curve of radius r with speed 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 df jyqffxiue3r*4t;d*4)t0 y from the road is equal in magnitude to

  Two horizontal curves on azv)/ bn2r5 7 )wnk7 oeu8pbbu9(be;jzh vh*xp bobsled run are banked at the same angle, but one has twice the radius of the other. The safe spb7e vb (w28hz)epj9u p;*v5bnz x7k)nruhb/ oeed (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 trac06lj(.m2 (e y(imeqf ,k ooskgk is not constant, but increases upward from the horizontal. Coming around k60me i.(q kgosjl2, fyome((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 oz/ t*mb)/a3*bg kn mmobject moving around a circular path to have both centripetal and tangential acceleration/*mb/3k bogantm*m) z ?

  The gravitational force between two objects isppsj .-2 qv mcfwd0k5: proportional to

  The gravitational force b7isdtfci 5f2q/ nski /un5t79itwg. 8etween two objects is inversely proportional to

  Two objects attract each other grav wn * sj 68p5pvpfoihta3yjy ,6ty5j81itationally. If the distance between their centtsa3pyw , vy65 p ti6f8n8j1j5*ophyjers is cut in half, the gravitational force

  Two objects, with masses y8sjakrj q/e3++ 0xbs6dpd3g5)h mus $m_{1}$ 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 masse r; xl (hcenbtbr;((w)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 gravs6m 4i3 zs5x,gfnnb8 jitation.

  Compared to its mass on the Earth, the mass v p8a1dltgmeu5 ;y0a (l1zvg2 of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth whatpwu6 (zfvdoe8 ;rlr 6 t;uypwd96j9i5 it is on Earth. An objep d(98;p9y;i 66v65rl udejwofru tzwct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's j7eqx;rwmq/-e1vyu, z tq62 vq: ndm: surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it ,2d6d s+fhthl beyond the pull of Eaht f+l6,s2h ddrth's gravity?

  Suppose a satellite were orbiting the7 oza cn4aj9 ,ehd+h+.shda 5uc0 .mxc Earth just above the surface. What is its centripetal acceleratios+oa a+z7h4hjc d,0h e.a9nxc .5mcudn?

  A hypothetical planet has a mass of half that of the Earth and a radius of ts*8: zg-vxnr v+z-9r) 5ru: rm/frs hug5fnil wice that of the Earth. What is the accelerati zumvr:+ ngzvu9* - r5s8/i s:l-rxr hgnff)5ron 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 r;xctq;8y1 c jwhat it is on Earth. The radius of the Moon is one-fourth that of the qc1t;8r;c j xyEarth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the/jf bt28scp0pq)3jg m radius of planet A. qc 8sjmfb/g)tp3j 02 pIf planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gr0c5ytpt6,hfw /p8whnavity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radiuswh pf8tnycw6 ph,0/5 t of planet B?

  Consider a small satellite moving in a circ.xq9wmu q :b8vular orbit (radius r) about a spherical planet (mass M). Which expression givq.ub:w 9v8mxq es this satellite's orbital velocity?

  Satellite A has twicv7bpxvi0 qy a 4aw-6n6e the mass of satellite B, and rotates in the same orbit. Compare the two satellite'xnpw60q6v7yaba i-4v s speeds.

  A person is standing ona3/ bf-wb zggkm;k 4cskn/6u5 a scale in an elevator accelerating downward. Compare the reading on b gaumk3f/c -;5bknw k6 szg/4the scale to the person's true weight.

  Who was the first person to realiz:bp g(4h pdd vd1:bs-i ii74tge that the planets move in elliptical paths around the t14vdbi ph(p id::74 bd gisg-Sun?

  The speed of Halley's Comet, whild )4q*ofef7pre traveling in its elliptical orbit around the Sun q4er7p)*ff od,

  Let the average orbital radius of a planet be R. Let the orbital p4j7 rdmtfk zj28k*utp)qg 2b0eriod be T. What quantity is co)0tu4kk7tq8j 2 m2rfz g*p jbdnstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeda, wisig4rod4 v2p+th the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of our Sun, what will the p p 4vg4r+iod2seriod of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance fro;;o(e8echi; 1eovhp bm the Earth to the Sun is defined as one "astronomical un h ;h;o;(bevo8c1ep ieit" (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.svpn;6 l:g;du+ko jp 0

  List the four fundamentallsj+2 ph)/qc8- zvql d forces in nature.

  An object moves with a constant speed of 30 m/sotibzkj 2 3m.p;rp,x5 *xpfk0 on a circular track of radius 150 m. What is the acceleomjrp,*pzk.x3b 0kt2 ;xfp5i ration of the object?

  The maximum speed around a level curve is 30.0 km/h. uk;5y e6 aw8z +dff/ycWhat is the maximum speed around aa +8fcyuk5/de wf yz;6 curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bhcalem8 to(orw83f 2s4;zp5 bicycle wh f82 alst;84mp3z owb(h oer5ceel of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.20:p.:r 9ef.o:wsb isrw0 m from the axis. What is the centripetal acceswoe:w i :p.rb.f:sr 9leration?

  How many revolutions per minute must a circular,gkz; ,z*zcoo 2v 8qk2a rotating space station of radius 1000 m rotate to produce an artificial gravity ofgzkqc8 k*zo22a,ozv ; $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. Ittm+ej:ar*m xf+6qy r8 goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcy 6 tm8*f qej+am:rxry+cle?

  A 0.50-kg mass is attached to the end 0yj3d; xwh: kcq)xc4g 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 3xqg 0);3 cyx4djhw: ck50 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 stron;k )puf :nvx*wiqp,u/g 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 weight. The stone's speed at this powvp uq :un,)pkix/;*fint is given by

  A stone, of mass m, is attached to a strong string a7a( ,uj 4wbnnesji2o , s2nof-knb9 o8nd whirled in 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 t (4wa usfb eo j j,9ki822n7o,nnnsb-ohis point is given by

  A jet plane flying 600 m/s experiences dy bi5u usgkkr* 1nf+8)*bh2u an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane iskuy) frdh b2 in*gu5+s*uk8b 1 flying?

  A pilot makes an outside vertical loop (in which t/sww ,m 9j*:o5il,/ b 8kznrbkuc.gs uhe center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat with only one-half of his j/wbl. sok ,5mku, i :b*w/znu98cgrsnormal weight. How fast is he going?

  The maximum force a pilot can stand is about sevla e2gqe.ti61zi/5g ken times his weight. What is the minimum radius of curvature thatg1i .zq/l5aik26 etge 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 tn) )nctt*7ia+ x8vf+w( bghpan 80-m radius horizontal 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 t)nvw7p) +c b+ ha(x tf8g*ittnires and each road surface.)

  A car is negotiating a flat cd ,;nvpdd f9t1urve of radius 50 m with a speed of 20 m/s. The centripe1d pnf,;dt d9vtal force provided 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 m at a speed of 14 m/s. Whatw,,+z*feo*f7d8m ab quy jisv ;fg3g; must be the mf+7g oz*d jby s;img;,vw,*efuf 8 3aqinimum coefficient 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. v )x0wssi/ic9hr( ; ,d:w +tgi(tgi uuThe coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay on the road?c9tii0(uxisg; rt+vgiw(h: s/)d u, w

  What minimum banking angle is requiredqv (g8,ydecl7x;+ ikq for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skiq lg7 q8x+(vky;ec,didding? (Ignore friction.)

  A horizontal curve on a bobsled r-i(/yq6 vl / vo,cnexyqw x/4iun 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, banked at an 1rbtc,y:d d/zo g-kz:b i;.lg angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at c mx6nwe 6:4bpl)d(gw(guon ( $45^{\circ}$. 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 revol+8 2 sf6tna5cnix5 jzbving uniformly in a horizontal circle of radius 5f6ia+j z528btx csnn 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 2 6xmh ust faq.ai-4ihicmyo 93 d -r.(k+3vzcto a speed of -.4.mzsi h axud3 o9q tvc+i( fhr ky2ca6-mi345 m/s 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 pd1a5ty40tf vf2iz2l 98cxb oyroton 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 gravitationa;nz g(zm qisy3-2 q.ill force on a 70-kg person standing on the Earth, due to the Moon? The izi. gqsq ;zy(n2lm3 -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 between two mt *a(5: oqioc0zt+j9, cr,yxgp(shilasses is F. If the masses are moved to half of their ini9c*5yilcoga s(+t z:t p(rx ,0,qojhitial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance frg3.x)kr/inp2;yx via/ y4 l-r vvg nc/om the Earth will the graviiap 2x n4/l.c3; /k rxyvv -vn/gi)rgytational 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 ivsp )0f4o4(nxv b4wthx raw)7s $7.4 \times 10^{22} \; kg$ 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 distance above the Earth equaltznpt, opsc)bvd:37 s2o q7+b to the radius of the zs: sp+qvtob 7d 2b3)tp7c,o nEarth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the *c5rgc hi (gws4o; ok8Earth's surface will the ac gs ;oo rckgi5*(ch4w8celeration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 (kxfshw .bk (+w+ g7nutimes the radius of Mars. The acceleration of gravity of the satellite, k s.(kn fxh(+ww g+bu7as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet r/ 2nmuge5-+9nndllt's center, the acceleration of gravity is 9m2rt+nl/nnge5d-l u $32 \; m/s^2$. 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 radius rqh blv 5n0rt6*. If the object is raised to a height of 3r above the Earth's surface, htv6 50lnbrq *what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes from muv87 b.o)o dxsea level tm8obo)vxdu. 7o 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 1c3no7om5 +o sl00 kg is at a point 3r above the Earth's surface. What is the sa m3ooo 7l5sn+ctellite's weight?

  A spherically symmetric planet has four times the Earth's mass wwi 3z1 q3kbh.rzkgi9u 9 a1a(and twice its radius. If a jar of peanut(3ziara kw9.q3 1gu9hb1wzki 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, a o7rx+gzv )k+ bnn wu bc/pu043lf-p(mnd Sun all lie on the same line, with the Earth betkmuupo+ wvc7f0rb ln) 4zg/ pbx+n(-3ween 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 balljl46 bwhwfml 2fqw s..;k9rh75z k7v k is transported 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 Eartjqfgw1qk;ruc m 8pw5e1nx (-(h (i.e., it just skims the s1j qprfx-wcg;5(qw1(e mun k8urface of the Earth). What 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 ortp,bc0rd+f 5d bit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revo50ddftb,p+r clution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above th7d3bo i f*ec ow3;u+6o)vgyq te surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the Earth is of 3o6tw7 bq g+yd)e;iv *co3u$6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupia5. - saywki-uw:id1rjym9ha ,sw +rdzkz40 6ter, 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 orbi6q(13rc sdwv(d- fpix ts 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 rtn;w+ iv;j.fj8say:(maw 3 h brg;ji7, and moon B has orbital radius 4r. Moogwr8f:;m3 ;iji j.s(a;+7b y wtahjvnn A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is294yw6/8p,;y/c emdsz+idp wdwwrhb $7.78 \times 10^{11} \; m$ 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 the aver so7.ud 6lz5igage distance from Jupiter to the Sun? (The distance from the Earth zi5 . s6gdlou7to the Sun is $1.5 \times 10^{11} \; m$.)