Is it possible for an object moving withowq ) mt)-hu0o a constant speed to accelerate? Explain.mtw)o u-hq)0 o

  Consider a particle moving with constant speed sump9 (j qp/.i/btq pwmez)w c- syb.(g4ch that its acceleration of constant magnitude is always perpendicular to i. p.b(/ s9w q()y4pbjpm tz /gim-ecwqts velocity.

  An object moves in a circular path at a constant speednvggxm2v3 4*e . Compare the direction of the object's velocity and acceleragvx 3*vgnem42tion vectors.

  When an object experiences unif 66coqx+bj*axauuz y d+:,e :uorm circular motion, the direction of the acceler ux6 u y+ue,bzq6c*+ jx:d:oaaation is

  Consider a particle moving )ood qm4jub .4with constant speed such that its acceleration of constant magnitude is always perpendicular to its velo jm4).4q oodbucity.

  What type of acceleration does an object jgbpa; g(ap*j;ou(,f. 7lptxmoving with constant speed in a circular path experi lx;f(pab7pgpa;,.j go ( t*ujence?

  What force is neededae( pa+i+c5pa 5dhty9 to make an object move in a circle?

  When an object experiences unifoh k+axv2 :jd9drm circular motion, the direction of the net force is khj2+a:vxdd 9

  A roller coaster car is on a track that forms a circular loop in the vertical pchtex), q2bi yz*-a9yl8fwj )lane. If the car is to just maintain contactaz,yw9 ex cj* ))h28l-fiyqtb 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 that forms a circular loop (radiusz)hu p(t v tdjs*)npph2(e(t/ = rhhtnt/)j ppp (zv( )2(tdues*) 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 its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc unc;hgv9v ja0q)1p z*yc j 3bzy k04 yn)xs9ild0til it is going straight up. Just as the plane is at its qczp 0kvyy 4cbv9;0ly zxh* 3n0i gasj)d)j19lowest 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 c*fjzy9)5r w cf/t a5v5i5kvauurve 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. Thtz/m0 j ae pnba e3196n*kcz:oen 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, como tenk z e*0/9:a6czmbp3a1jnpared to the first time?

  A car goes around a curve of radius r at a constant sn7; m-69b7hrhg t ret1x 5rknvpeed v. Then it goes aroun9rrt;7g vt-mexh1 nh567b krnd 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 first?

  A car of mass m goes around a vrd qjldm3ytn 840*t. banked curve of radius r with speed v. If the road is frr.nvtd8qjd tm034 l*yictionless due to ice, the car can still 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 bobsled run a0 fmjpih lei 6b5d5kjj) q2z/.re 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. Wjh p.5b25qd0m6ej kzf liij )/hat is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant, but in,ahf1x of8;ws 4-hk2 n3jooxrcreases upward from the horizontal. Comi ;o,h3afow xo8sx24fn 1r -khjng around 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 an6 21+/ldu;z1t- aplfq vldwa)e ujtt- object moving around a circular path to have both centripetal)ld el+2u1a6qf/-t d jlw 1t v-zaut;p and tangential acceleration?

  The gravitational force between two objects is proportional ta.x; nyxgzk y4s44tc q/5w q+co

  The gravitational force between two objects is inversely proporkw+bu:-h0ei t p q.+srtional to

  Two objects attract gzba8 w 6j2 87 7qwq2)fmvyzak1dxn8 yeach other gravitationally. If the distance between their centers j62a)2w1yyxna dzm 8f8 vwqqzk78g b7 is cut in half, the gravitational force

  Two objects, with mash)3j dxp ))pkxses $m_{1}$ 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 masse2 smvg93tl5j)sy7 5r7 fokylps $m_{1}$ 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 gg:k5bnmb6 zn7w;,qb;tu tqsu2., vu xravitation.

  Compared to its mass on the Earth, the mass of an object on the Moon i)/f*iaxu3q/i4 yt fwhs

  The acceleration of gravity on the Moon is one-sixth what it is on8bjik3s k8ab oo2. f 6up vs4d-.ifjc) Earth. An obje.p-ik bvsud b fio.kj2 8a8s4j)3oc f6ct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface,tb*gg ew/ pn a63e7y5fkhv*2f the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull of Ebr2*zlsq4i eit+b : n;arth'sn *+;zbe2i:sqr i4ltb gravity?

  Suppose a satellite were orbiting the Earth ju8whd35 7; izggjeq oe(y 0g;obst above the surface. What is its cioog 357;w(0;hgqgz jb8dyeeentripetal acceleration?

  A hypothetical planet has a mass of hu9of9pl.u9+ :c pxetralf 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, the accelerat +t:e9 l.9fo9u rucppxion due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. 6msha6-fvs )q wz0p7 r The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to thf)7 z0 6hmqar-6swpvse Earth's?

  Two planets have the same surface gravity, bu 7o//9eqhzbp t0hxth-b3k hy2t planet B has twice the radius of planet A. If planet A hayhh/3b2t eqtzh/xk90bh o- p 7s mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B h9 xc9ugnwoju2df cns j3 /5p-8as twice the mass of planet A. uswdncnp99u5 g/j2oj-c3 8 fx If planet A has radius r, what is the radius of planet B?

  Consider a small satelliz rkyndj4wocv2 og,2)dt9 0w78ysza7 te moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orojdswv4 7gt n0,8d2r 9z7woz2 yacky)bital velocity?

  Satellite A has twice the mass of satellite B, and rotates in t3qz+fc(ezpb 9p65yw+kjfe8 the same orbit. Compare the two satellite'swqe 685ky+9(b t3p ecffpjzz+ speeds.

  A person is standing on a ., h1 tq akpd9bibo;z*scale in an elevator accelerating downward. Compare tz ;kt op1d.h b*qaib9,he reading on the scale to the person's true weight.

  Who was the first person to realize that the planets mo usyd).zd7/je-v;rl ove in elliptical paths aro/odyes rd;ulj 7z.v- )und the Sun?

  The speed of Halley's Comet, while traveling in its elliptm,f44admcr/ o ical orbit around the Sun, oamm4r/ 4cdf,

  Let the average orbital radius of a planet9nz :*en5ml4 fa*u6 2clk tmez be R. Let the orbital period be T. What quant*zclkl*ez6t:5 en2a4 fm mnu9ity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromkam2.qxc cm1z owrqidvp ;;;u af 0*02eda, with the same orbital diameter as the Earth around our Sun. If that ;;x2 a.pwvzoi aq;*m0f0c1qk2d rucmstar 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 the Sun is defined as one "asr8vq qp :04gi84mavp3svpt4 wtronomical unit" (AU). An asteroid orbits the Sun in one-th8rmg3viv4 p0p q 4as:v qp8tw4ird of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.mxo(q: tiar4m-9 z eb-

  List the four fundamenta 6bq*9 tkahv rm1/oc9ml forces in nature.

  An object moves with qglx/qcdhm-f,4 n/6ea constant speed of 30 m/s on a circular track of radius 150 m. What is the acceleratifl-qdge m,/h4c/nq x6 on of the object?

  The maximum speed around a levbtn-f-g3 x2 vxel curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors f3 --v nb2tgxxremain unchanged.)

  What is the centripetal acceleration of a point on th adrrg7i2; 6wevo k57be perimeter of a bicycle wheel of diameter 70 cm when the bike is moving 8.0 agev6wkd ib5r27ro7; m/s?

  A point on a wheel rotating at 5.001q gqv xqy)z.pi+(8 ye rev/s is located 0.200 m from the axis. What q yq+q) i1 gvze8.yx(pis the centripetal acceleration?

  How many revolutions per minute must a circular, rotating9hz8i*jn uc,o xt *9sq space station of radius 1000 m rotate to produce an artificial gravity ontu,*q *8six9jh oc9zf $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at 96.5 7l8 ingtg(/abkm/h. What is thebag/ i7g(n8tl centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end e-owwdmg+fhc g.l + +,hjnp *)of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension thatl+ mo)jhc+,.p*wgwg+ e f-hdn 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 stpl g8/;yfiu: 9srb; 0o u+mkikring 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 oyr8u:;lku f;mis+ 0k/b9ipg this point is given by

  A stone, of mass m, is attached to a strong string and whirlr kv90* re8wx-b*naio ed in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 tw0n-8v9 i *eb*xrakroimes the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/su h80wk21w rd9uvnv;oguz . . cszl6c- experiences an acceleration of 4g when pulling out of the dive. What is s1v..0z6cw hrnvw-g ul2;okcd 89zuu the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outq9id(5z)k f ar;art2l;xqy6z side vertical loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on h; kdzatz;xil2r f)q5 96a y(qris 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 weoa 4x-z;k)bgv lzc8k1ze t:d:ight. What is the minimum radius of curvature tha 814c-lexz::kozav t)kz ;g dbt 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 an 80-m radius horizontal cunvb.aa qho1k 9g;.e e-rve 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 frictio ae.;9g-o hbqeavnk1. n between the car's tires and each road surface.)

  A car is negotiating a flat cus6ijeta80v j 1ban1,b 1yxoe 3rve of radius 50 m with a speed of 20 m/s. The centripetal force pro jxb 3b8a61veatn0 ji11ye,sovided 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 te4 6yc3.8n yxu4 wgvh50 m at a speed of 14 m/s. What must be the minimum coefficient of friction beth4 c yv.yt86 uwegx4n3ween the tires and the road for the car to make the turn?

  A car is moving with a constant d :y+ao 9v o*2rclo;ozeb*g 0jspeed v around a level curve. The coefficient of friction between the *g lcbvyo;je +oo 2or dz0:*a9tires 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 bobsw ,gh d9nve*)kled to negotiate a 100-m radius turn at 35 m/s without skidding?nv e,dw*g9 )hk (Ignore friction.)

  A horizontal curve on a bobsled run is bano6;kpr7r bv, m;pg5/66 lz xzei j8rvqked 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, bangaa :;hyn 91xdked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 ig+u -zf ./h tfsz65atmd 2d9hm is banked 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 revolving uniformly in a horizontal cirwh* icu 5:lvy,cle chy* iw,5ul: vof 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 a5nwwembql ucqwiayy j2e);g:4v. 3k 8v/ i8g.ccelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical value in the blanks) wy4.q l.vye8/q be:vang2iwm ;g)ji35 ukwc8
(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 or94 nk 1ixi2ejf 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 Earthegv:jj +lxpun* 1-ae 0ul7m/y, due to the Moon? The m +ujj70 enmyegx*uplv-1 :/laass 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 attres(o skjg3w:y/ (, tzfactive force between two masses is F. If the masses are moved to half of their initial disw(,tfse j/kgy 3 o(zs:tance, what is the gravitational attractive force?

  For a spacecraft going from toe.h2lwxjctge8.za02 6 (ao fhe Earth toward the Sun, at what distance from the Earth will the gravitejxgo ho. z.2ec 0ta628a fw(lational 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 is y/g0gi6xt ,f f1om. rgmlfk6-$7.4 \times 10^{22} \; kg$ 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 equal to.mocr//+vyut 4h/khk+g7 kto the radius of the Earth. What is her acceleration due to grac+y// ko/r tmkh+ho.u7g4ktv vity?

  The radius of the Earth is R. At what distance above the Earth's surfacp+ 5m vl2hem460nq idxe will the acceleratio 2h ep5 mm6qdnvx4i+0ln of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars att5 y*dzwup8,7inbzpjb y5*k) a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the s 578iyn),*b* bzutp jpydzkw 5atellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleratio8vy 0y2*vs9gj*sx 4guu/r m 3) dssqyrn of gravity is)/jdv4rgyg 2u38y*q r0s*msuys vsx9 $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surface4a 17- ugoswy ,qe9,uzyxu7cw of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its wei u 9swuug 1ayz7e4w,o-q,yc x7ght?

  By how many newtons does the weight of zvvs-( 560e g3qpydqveot2d9a 100-kg person change when he goes from sea level to an altitude of 5000 zvv2sq9(qdd3ogv-6ye 50 p tem? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satelj41*nvq w s-6ec3rqq.p c+g emt*k 7hklite of mass 100 kg is at a point 3r above the Earth's j pce-+k rq**47csw6 nh 1qemk.q v3tgsurface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass andw53gbfmegu , b4 iz5v5wfny 1) twice its radius. If a jar of peanut butter weighs 12 N on the sn)f34w 5e 5bguzyb1 wvig,mf 5urface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, ,v 4 coadgh( d9apyo-f92ne/vthe Moon, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Movdaa 4n fogv e cd,9(hoy29-/pon 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 transportwrx:xqza+y*qg9d0 p 6ed 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 f5 2ge+h1u ctklwfg64the surfafck e4uftl2g615g+hw ce 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 orbiqlste:uy5zf 65w,u4qt about the Earth (i.e., it just skims the surface of the Earth). How long does it : uq6 5tyuqfs,z54elwtake 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 230 km above.,wkn8 9owhsi-s 9q zj 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 of wjs9qo8.wsh nz-9ki , the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an ig.4es(re g frz p)9:vorbital 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 radtccg;43l;e ul ; ler:vius of $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a plac)/bms0hd l j( tff6zu; cz3w6sd8o0f net in nearly circular orbits. Moon A has orbital radius r, and moon B hajz/fs m0wlf0uc6cdd bhst6f38; (zo)s 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 is 9,+zpqur d3gwa d 5x+z$7.78 \times 10^{11} \; m$ 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.u)yaxq58 jcqv,fpg. is the average dig q.p j)ac x8yq.u5v,fstance from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)