Is it possible for an object moving with a constant speed rz c+*km*l pc4to accelerate? Explain.cm* ck +*pzl4r

  Consider a particle moving with constant speed such th2o 9v0jxfhu7 xat its acceleration of conovju2790fh x xstant magnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compar31- zsh su4j8 ,1 .ujvxhnwivpzysn: nk5a0 f3e the direction of the object's velocity and acceleratu5 3zj:yp1x -hn., w3i a8hnkz1sjvf0sun4svion vectors.

  When an object experikbatn o8g5o- 2ences uniform circular motion, the direction of the acceleratn o8okg-at5 2bion is

  Consider a particle moving with constant 7 mya8umm h op6js0p; 5l4,foqspeed such that its acceleration of constant magnitude is alwaulmp4oy a0poq m6s75jf 8 m;h,ys perpendicular to its velocity.

  What type of acceleration does an object mo50gce 2o ouig5ving with constant speed in a circular pac2iou5g5o ge0 th experience?

  What force is needed to make anhnude appe5:i/,f ,:l object move in a circle?

  When an object experiences uniform circular motion, the direp ev 6 d .ki(k:t,py9b;fau,uqction of the net force qt,ppev69db y.i :uku fa;k,( is

  A roller coaster car is on a trackd 6y()o t2mqfo 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, what is the minimum value fqt( dmfoo2)6yor its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circula osng (8.78xux2v tsjmr loop (radiusog s.m8s8t2u(njv xx 7 = 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 its speed at that point?

  A pilot executes a vertical divh 7spju*(t,h ( t49wdjmbw7gc,2rjh xe then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest poi9,g*rwmh7 sjcph2 twh,j ud7x( (bt4jnt, 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 curds aar7plxx 6iph d8e:))r 3d(ve of radius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curvx8o(byasdd1jjehd 1f / i3 dd72 7yvn5e of radius r at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripe a71ifs5yj d2h/ yd8xevj7 (1do3bddntal force on 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 r at a constant speed v. Then it gf:4 e id4qwf;ooes around a curve of radius 2r at speed 2v. What is the ce4wf: qi4o; edfntripetal force on the car as it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r ib5z 4wnd d)-0v*ftcvze 1(gu with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of )-5d fv0(diuzb4 c 1*t wgenvzthe normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run b 7isben3,le:*-tcyl are 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 b l-*eyi:7 selnb3tc, v. What is the safe speed on the larger radius curve?

  The banking angle in anl pt)8tdn) fvvm*q-+uv s:9v turn on the Olympic bobsled track is not constant, but increases upward from the horizontal. Commvn:t f8 s-) 9+vv)ltq vu*pnding 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 moo:h1m h8f zib):(q +qmo4ztdcving around a circular path to have both centripetal and tangential ac+h8 (m)t:qf1:i h4zqombozdc celeration?

  The gravitational force between two obje zpjb4 t;9n0 h9f4ieohcts is proportional to

  The gravitational force between two objects is f4ldl11m.; u ljfm9ma inversely proportional to

  Two objects attract c:jy: 5s qhun,+b4yujws bq8:each other gravitationally. If the distance between their centers is cut iyjn :: ,bq4y qucjh:ws5sb+ 8un half, the gravitational force

  Two objects, with masses :9rd8*iup u zk+lq et4-zzx-h $m_{1}$ 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 mass:fg;w2 b-(q /r rzgv8gkwb.iklnl4vlg, f0 )aes $m_{1}$ 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 univerfyf, .sn0kzk90 tmc+i sal gravitation.

  Compared to its mass on the Earth, the mass of an object o1ivf1( u-ik yf4 ezca,n the Moon is

  The acceleration of gravity on the Mox -tsacf+(11e/s ys tzon is one-sixth what it is on Earth. An object of f(sz-1tt ysae csx 1/+mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's web: be8fec6ah.4z ybj*ight

  A spaceship is traveling to the Moon. At what point is it beyond kjla58ijg 34 othe pull of Earthjli8 g3oa 5j4k's gravity?

  Suppose a satellite were orbiting thebwaqvzyz4* 5o) g(/aaml r0 *ete 0g;. 7gfilw Earth just above the surface. What is its 05ia;tlg*)0 zg e/w7 v(lw*f y. e 4azoaqbmrgcentripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius ofy6*0a5gyozddp h( aj4 twice that of the Earth. What is the acceleration due to gravity on the planet inz *46jd(a0y dayo5 hpg terms of g, the acceleration due to gravity at the Earth?

  The acceleration of fqcw10b66hyz) ;qobs gravity on the Moon is one-sixth what it is on Earth. The radius of c1q0s6w6hf bbo )qzy;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 has twice the radius dkb x tk:i9 hb;30 b6iu*ckfn61 thv6pof planet A. If planet A has mass m, what is the mass of planet B?f p;6* khd39xtci6ntki bhu6vkb:1b 0

  Two planets have the same surface gravity, but p-tg 3nqy ./erslanet B has twice the mass of planet A. If planet A has radius r, what is the radius of p3tegsq/r y-n.lanet B?

  Consider a small satellite moving in a circular orcsvvt (0/hh6q bit (radius r) about a spherical planet (mass M). Which expret (0/6hvh svcqssion gives this satellite's orbital velocity?

  Satellite A has twice thegxpo2 go4 vhc5b.ap+y;dxem a; 8;a o7 mass of satellite B, and rotates in the same orbit. Compare the two satellite's spe byg aa7. ge4;+oo5phoxamvxc;d8p; 2eds.

  A person is standing on a suj2ld dl4qq bl7 s+k;+b)i/es3io3f x cale in an elevator accelerating downward. Compare the reading sfkdx l3 iise7udo4/3+qjq ;l + l2b)bon the scale to the person's true weight.

  Who was the first person to realize that the planet mt *m6nvf2y2c1sd;xbs move in elliptical paths arouxs2nb d1 *mv6cf;tym2nd the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around the c 5yx8+rpc3v up47sh xSun+3h74 5 xp vrcypxuc8s,

  Let the average orbital radius of a planet be R. Let the orbiw,cid:7 f6x;i f9mkl ltal period be T. What quantity is constant for all planets orbi; w dx6,f7c:k9fllmiiting the Sun?

  A planet is discovered to orbit around a star ,cmj,qgm5g;oc/5 dnbp oh 81v 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 pl8c1 dco5/b5 ghmv,np;j o,gmq anet be, compared to the Earth's orbital period?

  The average distance from the Earth to 5+wmfa dy )d9cthe Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun)cy dmaw +f9d5 in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.z, a0kwbgc4 q-

  List the four fundamental forces in natue,j(kl ab2ki8re.

  An object moves with a constantyxbt6d5i3tva dl)t +3 speed of 30 m/s on a circular track of radius 150 m. W3t5d3xd6+vl i a)yt tbhat is the acceleration of the object?

  The maximum speed ar yyvs1-fxnb96e u3tud4a4wm 8ound a level curve is 30.0 km/h. What is the maximum speed around a curve wif -a9yd4u38s xwvey4t 6mb n1uth twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on k i2b7*utm gfsq(qc1h.-pz;xthe perimeter of a bicycle wheel of diameter 70 cm when thxs2t mhbzqic(7f. u1q ;kpg-*e bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locate8 e s; ebxp:dmblg466yd 0.200 m from the axis. What is the cent6 dxyeb;p 8m: bl6seg4ripetal acceleration?

  How many revolutions per minuwbt z5 xghh(;;i0f mf(hqe:r 39 hrs5lte must a circular, rotating space station of radius 1000 m rotate to produce an artific5hs:i0he h3rzgqm( x( ;9ffwtb l5hr;ial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. Iy;e45 c wdc l+tqo90beuh,b: wt goes around a 13.7 m radius turn at 96.5 km/h. dq:+ lo95,cc4ubwehe 0ybw;tWhat is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached j+rpj y o 7h)sotid918to the end 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 maximum j79 sty1o) +o8jihpdr speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and j tdgqj* 9.rdr41f 8zbwhirled in a vertical circle of rad4d8rzrt. jdqgjb *91 fius 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 point is given by

  A stone, of mass m, is attached to a strong string and whirled in a verticaljwl8d4rtxa1 ( circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The storw41x8j(dat l ne's speed at this point is given by

  A jet plane flying 600 m/s experiences an accelni4r5+zr r tx*eration of 4g when pulling out of the dive. What is the radius of curvature of the r+rrtx5 * 4inzloop in which the plane is flying?

  A pilot makes an outside qd6y :5wphni 8(3brfqvertical 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 his seat with only one-half of rw6yifpd5b nh:8(3 qqhis normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times hisz jv)b+d6u4h k weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a verticalvu h)d6 bzj+4k dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 8smeek(x-g q )+mfh;d70-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 tires and emqh -dfk;s)g7+me (xeach road surface.)

  A car is negotiating a flat ox+,cv.i;qvnx w(ny ;curve of radius 50 m with a speed of 20 m/s. The centripetal force pro ,yni (cqvvo;;x.+nwx vided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve olf8p phltccf1-5f5,puprg 9.f radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction. gcht5lf p5ucflf1,p 9p-rp8 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. The coefficient cr8*kq( xg1koq(fj+ fof friction between the tires and the rocfk(rfx jqg(*+o8 q1k ad 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 requireth19, :5kty z /5nnh cqcp4v5 eiomlu,d for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictionuh1/4ct ntnic9:m olk,q5h5v, y 5 zep.)

  A horizontal curve on a bobsled runeq9p m8ksx1z7 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 2iy9t0xf)xg b m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked jm k: /xm/mlx,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 revoey5oo 3n bek(9lving uniformly in a horizontal circle of radius 0.500 neey9obo3k 5(
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 ix i ed4c2f3uu;n the pit area, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (c;id 3feu4u2xonly 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 proton of mas y-u*;oppf22)l( inr4;wtxkusrw zk/ s $1.67 \times 10^{-27} \; kg$ 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 Earth, due j 9xcw8 (a p(:l uvsd1v/yjfm;to the Moon? The mass of the Moon i wjy(usv8 /fd9c mj1(v:xpla;s $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masd1 k*+ynm)zwhiy5z r g9n0 ,frses is F. If the masses are moved to half of their initial distance, what w05rzgmkz9fn n i)*yh+y, d1r is the gravitational attractive force?

  For a spacecraft going from the Ea++ wp*)lq 32e. w mmwbrzdg(carth toward the Sun, at what distance from the Earth will the qb zw(adc w2lp)gme*+rw3 +m. gravitational 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 Moonp:xo7no 8zi x9 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" ap)o6 -c1qo65(j .ogdn a yyilot a distance above the Earth equal to the radius of the Earth. What is her acceleration due 1o 6n yyc5ga6(.-opl)oi qjdo to gravity?

  The radius of the Earth is R. At what distance above t-ifxf-p2ss+ n he Earth's surface will the acceleration of gravity be n2s+-pf fs-i x$4.9 \; m/s^2$?

  A satellite encircles Mars at dk6ew; xypo133g(u:gah kj7j a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to doga x y7ek63 1wk;ju(j p3gh:the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the*z8 0m0euky 5nq mw,cc acceleration of gravity inc00eck*5zm 8w qmuy ,s $32 \; m/s^2$. 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 r.*ccst1 0j6hvki. n:g q.g 9gfsr8:ixi If ti r.t:g vs:1cngc86k9ix fs 0hq*. ijghe object is raised 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 person change whe9 c m-a r1zhkif:+jvh.n he goes from c hh.kraj:z -fim9v +1sea 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 is at ec28naf h;w*wa point 3r above the Earth's surface. What is the*wef 8a2w;chn satellite's weight?

  A spherically symmetric planet has four t e;gt5h,(qqfk imes the Earth's mass and twice its radius. If a jar of peanut butterkf hqt;,g(5eq 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 all lie on the same lin x/ z,vh0uynvbzer 8jmq*;m 1:e, with the Earth between the Moon and the Sun. Th*xy;nzmv r/1 h zq 0,jm:uvbe8e 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 todoefbvc t,44l :k or/5 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 justo., xyd vct0bm,l3/z.ic0 irc skims the surface of the Earth). What is the speed of the satel0.yid/crb, icmt03z,o.l cvx lite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circulf2 ja;c3r(z uoar orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it tak2 (carz3j; fuoe 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 the surface ofv e:axrft67 b) the Earth. It is observed to have a period of6b txfrv) 7e:a 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 Jupic. pw1 wboymmh68;7ypter, 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 diui 5af28q) bn./uc hradius 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. Mo0ny,m: 13 syuxjzfy 2+kbn4thon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long doyhytu :1y msxb43+nz2,nk0 jfes it take moon B to complete an orbit?

  The planet Jupiter is*i xfn sd68ab4q abku s1b:9+r;kn1 jp $7.78 \times 10^{11} \; m$ 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 thvkn ecjoum h3h-tt+v* dc6/j zd:* p52e average distance from Jupiter to the Sun? (The distance from thkvjo /je3 uczhnp+dcmt2h t: d5*6 v-*e Earth to the Sun is $1.5 \times 10^{11} \; m$.)