Is it possible for an object moving with a constant speed to accq5o* m/aqbfs+ ig:kbitlr0 .7elerate? Explain.s:qb* g5 mra/0 qb+kotiif.7l

  Consider a particle moving with constant speed such that its acceloky 7i 3.-nnwperation of constant magnitude is always perpendicular tonnoiwky 3-p7. its velocity.

  An object moves in a circular path at a constant sp;-h bstojizfjqnkd a.8kcb8gk,l: * 6u2 ud, 2eed. Compare the direction of the object's velocity and acb b gdjl2t6 ;,*d ucn.fu8ak,j-ikk82s:hzq oceleration vectors.

  When an object experiences uniform 1kzx 3n3itej) circular motion, the direction of the accele)kie z3jt31xnration is

  Consider a particle moving with constant speed such that its acci: q5ltro;v.)cen v 0ck)qj/ eeleration of constant magnitude is always perpendicular cie5qqv ) :ev.t0k;/lcr)noj to its velocity.

  What type of acceleration does an object moving with congxi w3 et 7jtbwo-.rsks ,(u:0stant speed in a circular path experiencek,sx-3 o.gjwr t b7us0: iet(w?

  What force is needed to make an object move idt:dr:;h h* xjn a circle?

  When an object experiences uniform circsu,6du ed-2 saular motion, the direction of the net forc-ds 26,euaduse is

  A roller coaster car is on a trgh22m nai.m()e cbmc7ack that forms a circular loop in the vertical plane. If the car is to just maintain com2 (iec) amm7nc.2bh gntact 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 (radius9i((x: ywfpt5r h5)ewh+u btu = 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 minimu uheb+fy(w:5hu tx i)p9rw5t(m value for its speed at that point?

  A pilot executes a vertical div ms7 p5w uvfi2/30;netpzdz n/e then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force onipevz fsp 7/t5;/d w 032zmnun 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 0 h8y2)cddckk 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/(b)jjxrf/2 lom 0f)nlmug: k at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force oj ()x mgm0klfl:)2 /bfunoj/rn the car as it goes around the curve for the second time, compared to the first time?

  A car goes around a curve of radius rtmpv:33* zi(c6o,lk ke m5ksp 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 firsev (kzm,*i:33pkmls op5 6k ctt?

  A car of mass m goes around a banked curve of e.ikf(*yjn; acok3g , radius r with speed v. If the road is frictionless due to ice, the car can still negotiate thee;.k3nc,oyf*ga ji( k 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 rf0fx.u, zy ;d 4/.vtq midknz7un are banked at the same angle, but one has twice the radius of the other. The safe spfix .u0 n,4mkt; 7qfd.zy/ vdzeed (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 track is not constant, bg9gmhi3faav8 -v61zoiz 9 f*dut increases upward from theozvzdf gh6f3ga9i1iv 8-m9 a* 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 this?

  Is it possible for an object moving around a circular path to have both0g-xu qbbv, a1n i)e0k centripetal and tangential accele1axibu nbke-0q) g ,v0ration?

  The gravitational force betwb*iz)pb)ekv8xsc ) i98czg3 r:nu u8veen two objects is proportional to

  The gravitational force between two objects is i: cc qq3g9lqp3sd n/0tnversely proportional to

  Two objects attract eoztz3lf myw0h-: 1 v.jach other gravitationally. If the distance between their centers is cut in half, the gravitaylo3t1.zzfwv:-0 hj mtional force

  Two objects, with maszmvozioknncb(5 6.b:y 2oz. ;ses $m_{1}$ 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 .eka)uz fz; s0 .m7jcy$m_{1}$ 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 unif7s+ -ehu 3wzerj sh:1*bov;zversal gravitation.

  Compared to its mass on the Earth, thx;y:yb.7xqkpy2a;c be mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on .ay .metu vt;*yi: t0d6n,h xcEarth. An object of mass0:ehnxmy;*v ya.ci, tt tu.6 d
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from tk.iql gy5x b3/he Earth's surface, the rocket's weight

  A spaceship is traveling to the kgf+11z 9n;d thkl/0) djgyea Moon. At what point is it beyond the pull of Earth's gravit ngkktgl0+ dz; 9 eyh1)f1jad/y?

  Suppose a satellite were y6y0r;dv8t e; i*gyje* e8dctoqw a05orbiting the Earth just above the surface. What is its centripetal accelertcr5tqd e80g ;i; dye8j0we**y6y avoation?

  A hypothetical planet has a ma(kf a l1xbi )ted87b: t1dtru7ss 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, the acceleration due to )b7k1ttdi :a(xd8fl r17tbu egravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is acfiayb-3 6y (on Earth. The radiyb6-f (a aic3yus of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B h l14vprz tl;t ergl:gh125gqj:6p fy6as twice the radius of planet A. If planet A h 2t 46zyhv61 1l5lj;pprtgfgl r:e:gqas mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass eg g6v( q+;svnof planet A. If v;ev(gqs +ng6planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) ab fox x fql19o*cgf8d/6out a spherical planet (m9 6oo*8x g/cxqfl f1fdass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the bq b;bp(t u ok(oy.9wh9/8qsamass of satellite B, and rotates in the same orbit. Compare the two sateb8 shb9tqao.9o; bk q(upy /(wllite's speeds.

  A person is standing ondq e67 ; j(pdnbwouvqy7ok0+) a scale in an elevator accelerating downward. Compare the rew0(j )q v b76e+no ;7oqupdykdading on the scale to the person's true weight.

  Who was the first person to realize that the planets move in elliptical pathnt kvwz:7m a1(5s3ggek:i 6egs ar :gtz v15aw:k73 gekme6( gsinound the Sun?

  The speed of Halley's Cometl(hc em(cn *rmq0l-wju duy-p pq/f n32)k(8k , while traveling in its elliptical orbit around the c-0fnq wcum kymph eu ()d2nrl-8/ (k*(3jpqlSun,

  Let the average orbital radius 05*rcqb qu(wej d;3h rof a planet be R. Let the orbital period be T. Whahcb e 5w*q(j0u d;qr3rt quantity is constant for all planets orbiting the Sun?

  A planet is discoveredb0 cmc,lsxa, al.(dkst0g-( x to orbit around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around 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 orm -a0, s0s,alt( kgb.ldcx(xcbital period?

  The average distance from the Earth to the Sun is defined as cj/8+y+ mr (ews4ijgdply 6( eone "astronomical unit" (AU). An asteroid yc(s/pigl( 6+ 4m 8eryjej+dw orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.v6 rzcm n,;gz3

  List the four fundamental fofc s hnpt-4i+;rces in nature.

  An object moves with75a2 -r pg uhla)r hc,+izumi+ a constant speed of 30 m/s on a circular track of radius 150 m. What is the acceleratio) au2rm ia7l+u-+zp icgrh5 h,n of the object?

  The maximum speed around a levz )3bkwsrik,0el curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all oth z0s3wb,i)rkk er factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicyc+,dwfc 8px; wnle wheel of diameter 70 cm when the bike is movxdw8c w;,p +nfing 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis.+ di8ic)fjvm h-kz2-h/zmz a. What is the centripetal dikih2/hvja.zzm+ )z-8mc f-acceleration?

  How many revolutions per minute must a circular, rotating space 0yszp( 7./ls1oxgrpow ;sm 9j station of radius 1000 m rotate to produce an arti;. ro7g o ppljw0s(ssy19zxm/ficial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes arounuvk50j m q:dss 4/uzb*xle9y/d a 13.7 m radius turn at 96.5 km/h. What is the centripes *sz/4bqkej 0vu95 mluy: dx/tal force on the motorcycle?

  A 0.50-kg mass is attached to the end ofvm6 ,: ozvfe tsip i01h e db0wr3;zy4+xogi58 a 1.0-m string. The system is whirled in a horizontal circulaesy6o zmdt0vb zr ivi,1g+hoe3p4w 0x;8f:5ir path. If the maximum tension 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 whirled in a v 0/lo5m*o7wfz ;dpudrertical circle of radius r. At the exact top of the path7o u0/f5;dzl*wdmpro 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 g(a/)n p( x8vq xpyn x*k(hy gs;g7bf4strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in thexh g qpy pnna)yb(/k(4x7 vfgs;8 x(g* 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 experiences as8+/ n uvr uw7yev-jg7n acceleration of 4g when pulling out of the dive. What s8 uvy7r7 /j ewn+vug-is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in1gtgf.,y 8w eg which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down .w, 1f8geggt yon his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stand i9l n 7nq b/wfya-qdv2-s about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can toleratdnq -by a9 vf2lwn-/7qe at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal czo9b gfn0w/ lmo xcc80 up087nurve with the tires on the verbnm 8c7pz u/ 9lf0o 0gwnc8ox0ge 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 each road surface.)

  A car is negotiating y;rc.gikt ck cuvz,+8986fe r a flat curve of radius 50 m with a speed of 20 m/s. The centripetal force provid9c.fzi8+ke,kuct r8r gcv 6;yed 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 speepm1z *)5aklgv/ /madud of 14 m/s. What must be tamkm)5uv z/*gp/ da l1he minimum 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 /)irg:d3 t/ (x egbbzb z:d*smlevel curve. The 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 thezbid/d(g rsbe:: tz3/gb*xm ) road?

  What minimum banking angle is reqili7/:oyvu(8rtd5g ae()t .jvl spi(uired for an Olympic bobsled to negotiate a 100-m radius turn at .d7jtoe:liipl )yv 8(vr au (igs/t5(35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled r bmd+v4hd;xbx 7rmz1 7un 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 angle t: p dt26f bu:q0h,+ nopyg4rrof $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 800zl;ua) gzr .b zwr2-c m 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 a 3iu xy) -1d3go80su)zyt 7ivsdx 9tdcb0;etuniformly in a horizontal circle od;v a) 38y7g3uy) tcsxd-ot0z b idte1s0ux9if 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 j,swo,g /c f+-tmk)ununiform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (f g o-mks,w)u,jc+t/nonly 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 proton5 hmhop +nu),v 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 standinu7id4 q3t e*wvg on the Earth, due to the Moo w7qive3 ut*4dn? The 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 twocslifi0aq/) 7 masses is F. If the masses are moved to half of their initial distance, w)c i ias/7fl0qhat is the gravitational attractive force?

  For a spacecraft going e uoyx,c3p5,t(rki+bfrom the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to+xt3 iu,kcoy,5rpe b( 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 x+x +i*))yod-hpfwha 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 distance above the E1 mcn/tgn86*em* en( jkx6edoarth equal to the radius of the Earth. What is her acceleraeno xgt*eenmcd 6nj6 1*m/ k(8tion due to gravity?

  The radius of the Earth is R. At what distance above the-.rseagpl2t55wb m -e Earth's surface will the acceleration of am5gt esw2le.b--r5pgravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 tiwnfvakk8,y xzeey )(1mj:9x* mes the radius of Mars. The acceleration of gravity of the satellite, as compared to the acce vnjm(ke)8yawe9kz ,:1*f xxyleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration p9nv9 v. x.wji8usyo2fa+0gux2hk:qof gravity 2kysjh+ vf x: .2iqn.auv99wg 0uxp8o 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 h(k)g/,nqge u qe*g(t has radius r. If the object is raised to a height of 3r above the Earth's surface, wha( ( )ne/kg tqeg,h*uqgt is its weight?

  By how many newtons d aiz:/u1mq qm;oes the weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Earth ism1q zmq:u;/i a $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r above the Ea8/ h+)ycqb17hp o62 fxohvkhf rth's surface. What ipch yfh27k8xoofv+ 6/ b)h1qhs the satellite's weight?

  A spherically symmetric planet has four a phyq:niuu3us k )7//times the Earth's mass and twice its radu/up/q:n7 3ka)sh uiy ius. If a jar of 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, ankq vt09hsu+z2z+/xa t:u5t u xd Sun all lie on the same line, with the Earth between the Moon and /tz:+u 95tuqxtk zhausx+2v 0 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 transported to the48fk u-gfn d:d 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 1 ;w+jzfn3 c,smn-pr aja6f3ft the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (Tz3ap-rf,jns1nw 6;jcam f3+ fhe mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just skims eo*6m4 e) s ,cmezsx0sthe surface of the Earth). How long does it take to make one revolution around t,mee60*)4zssxm cseohe Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface od71w)z uc-yhrtq: z 4bf the Earth. It is observed to have a period of 89 min. What is thq y ) uhrbt-z4cd:z17we mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has bfmgq83b*f-- t )a)uv w*pejf 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 wi,3xq .0hdvog.dp g cq1th 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 circul.s6fdxe nn)q;y :5jxyar orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. Ho.n;):yn f 6 x5xqyesdjw long does it take moon B to complete an orbit?

  The planet Jupiter isfurv+fw )t9 6h-mwu 5ejp).en $7.78 \times 10^{11} \; m$ 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 orx9fst rr6,c: abit the Sun once. What is the average distan c,:trfs 6rxa9ce from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)