Is it possible for an object moving with a constant speed to af3rq6ij2 h sr6ccelerate? Explainfr6r j6q2hsi3.

  Consider a particle moving with constant speed sucbg l5 g/bv.a3gc.q1bu h that its acceleration of constant magnitude is alwayv3bgl cb. g/aq5ubg. 1s perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare then lptyiomp403klq g.p.(to. 16ab2zp direction of the object' n4.l tpqap2t(l k06byz 3m.oipg1op .s velocity and acceleration vectors.

  When an object experiences uniform circular motion, t6t6oo0aopj3a vmi -x-he direction of the acceleration 6v xt 6-oao-0jpim3aois

  Consider a particle moving with constant speed such that its acci oym, 3y2)* ,oicgm)guox/rjeleration of constant magnitude is always perpendicula,i)3rjog,ucx i 2/)mgyyo*omr to its velocity.

  What type of acceleration does an obj4t.a/bgi *osh : a 9 elezlf:7c,l/fzkect moving with constant speed in a circular path experience?bazzich/:.*ffo9sak llle4e: ,7t g/

  What force is needed to make an object move in a ce;dn9 hr+akn )ircle?

  When an object experiences uniform circular motion,4)whv ncr(b .n the direction of the net force icw(.4vn )r hbns

  A roller coaster car is on a track that forms a circular loop in the vertic) c,f4m+yt6xa z;iu /j c7snu8dfdk3ral plane. If the car is to just maintain t7muydc ) nia6 +kujzs8rdff;34x,c/ 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 (mass = M) is on a track that forms a circular loop (radiubcbk8 k pjk+-syx-c6q*w*(luc yn )c .s = r) in the vertical plane. If the car is to just maintain contact with the tb.clpxy) *-+u( bkqc j-k8cyw*cn 6skrack at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertica0:4dal(,a5x h4j i xecob5ostja py6 3wr/o)al dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowesty p/6twoj aca:dhs lb4e 4x053a)j, xoa(ro5i 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 c1dctx.-sy )zyc; owt96 t,2 zsr7m:w q2vsp oaurve 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. u t9 iz) 1xu;ogxn78fl.kh+fg .8ghuzThen 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 tiu1 gf iku.+h 9f)lug78t;8z zxx .ngohme, compared to the first time?

  A car goes around a curs:a z82 6tuticve of radius r at a constant speed v. Then it goes around a curve of radius 2r at:t6uszat8 2ic 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 banked curve of radius r with speed v. If the roa p3tr ,;x2/ltlunl*qugs 5 b5gd is frictionless due to ice, the car can still negotiate the curve bl,ngqgx* t slupult2r; 3/55if 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 are banke7+lo, xx yfkd.d 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. Wh +7dlxfy.xk,o at is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not ci3p3irguxv 8lob1(u61 7u grponstant, 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 the1u rb pvu (lgr6ogp iux8313i7y do this?

  Is it possible for an object moving around a cirx nm,m07nfxa-cular path to have both centripetal and tangential acceleration ma7-nnf,x0mx?

  The gravitational force between two objectc vtw1+ xn8y /-azns86c o,nkds is proportional to

  The gravitational force between two objects is invers zjej;( rmie( vqls./7ely proportional to

  Two objects attract each other gravitationally(xf y.( yv/e2o6su oip. If the distance between their centers is cut in half, the gravitati (v( 6ey/oix2pusof y.onal force

  Two objects, with massespjuy)9.jds -k)y(+nf fm b+dw $m_{1}$ 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 wktuj6ek5qpyu/5 aa1.rt: . us $m_{1}$ 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 gravitaw:-.unq )bml( gmw j*dk+ y6 yex3suw/tion.

  Compared to its mass on the Earth, the mass of anp8nwob 4 i r8n*3+uxro object on the Moon is

  The acceleration of gravity on the Moon is one bta cg1vu;(1p 8g/+rbr lkg6r-sixth what it is on Earth. An object ofr ;ag/bu11 lt8b v krg6c+(rpg mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from th2 p8bn: uuel5g8std mw v*6w9ye Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is ilys , l) 6b7mp3oorve+t beyond the pull of Eao o+ esvb)3 6lry,lpm7rth's gravity?

  Suppose a satellite were orbiting the Earth just aba9 vgz1jdu9 furfjpi 6b m):7/ove the surface. What is its cend rmp/f7f19 uj9 6ai)j:vgzubtripetal acceleration?

  A hypothetical planet has a mass of t-5868mfy3sfeh u tql half that of the Earth and a radius of twice that of the Earth.f-8 ml3y5 h8fq6ttues What is the acceleration 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 wfs084v xr,r-dt a(nfe hat it is on Earth. The radius of r(a-ev rt 4fxfs,0d8n 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 4m3x c;0toqt ygravity, but planet B has twice the radius of planet A q3o;yxc0t4mt. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass of pg 3ddo6b;a 0 -z thk9ujk;xjb0lanet A. If planet A has radius r, what is the radiusu9tb03zka; o-djkbj h;d6gx 0 of planet B?

  Consider a small satik1m:3v q8w; pr*hxmsl*g 4hog*mgq 7ellite moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital velocity1* qm**4 m vlkrgi qgh;ho3xs:gpw8m7?

  Satellite A has twice the mass of satellite B, and rotates in the o -.kagfzv9-1zaik;;scbo ugyy38r he l )j5;same orbit. Compare the two satellii-s8b5-e3crygkojfz;.yz) 9g1ah vuk l a;o ; te's speeds.

  A person is standing on a scale in an elevab(vlby 0-uwe fkxplap7/ 8 tk58ze0c6tor accelerating downward. Compare the reading e/bvuf c8zx bpk0e (7y pk -860tlalw5on the scale to the person's true weight.

  Who was the first person mo6,lpu ;ulxr tfkq ,6y8n-0lto realize that the planets move in elliptical paths around the Sp , l68txqr6;ufumk-0 yol,nlun?

  The speed of Halley's Comet, while traveling in its ellipticaly. n li +nzh p+pdqq8ufvg*lb484l73c orbit around the Sun*p+3lnb 8hlq p4fiv7q48dl.yzgc+ u n,

  Let the average orbital radius of a plankd x0)sbve.o) *1x: g2xjeuyget be R. Let the orbital period be T. What quantity is constant for al)xjg)vg20u1e ko d.xse b*:y xl planets orbiting the Sun?

  A planet is discovered to orbit around a star in thxpmhs(m/tpp,* c. /kn xc 7n(me galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass ofm(mnk/n(/c.p7h*p ct x x,pms 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 d ,1jr 06 lanr+*j4kecm hxby3nefined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distancyrnc hnrme40a6*1bj, 3jlxk + e from the Sun?

State Kepler's laws.s3qts g)6pwrvy;56na f7sy3 k

  List the four fundamental f vznq o js+*x)z/5)gv60vdfd xorces in nature.

  An object moves with a constant speed of 30 mya)/3bgw gqr(-i+qi .n* gngfys *h:y/s on a circular track of radius 150 m.ynq ibys. iy+ h3( ga:r-q**g)gfgw/n What is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the b0uef k(wqk(- onf 5-smaximum speed around a cur wne-- kuos((b05fkqf ve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimgyjj 6iztkx6 )(1y:mxxw:1( xq:lu eheter of a bicycle wheel of diaxm j tj1zlix(q(:kux)y6xy we::1hg6 meter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is lkwj ,rw0 4rahcf9en 4:ocated 0.200 m from the axis. What904r4aw n,wr:cfkejh is the centripetal acceleration?

  How many revolutions per m/kajyg* a/+f6jnz h:y 9b4u axcck*0 finute must a circular, rotating space station of radius 1000 m rotate to produce an artificial gravity x0k yu/+ ck a*:6a9c/gaj4zn yhjbf f*of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 1lu1bvw/an;bl./x t-xyg*yx7 ak4o ( q3.7 m radius turn at 96.5 km/h. What is the centripet - bx( b/yn.v/ag1tly * kwx;lq4uxoa7al force on the motorcycle?

  A 0.50-kg mass is attached to the end -7rj1z/xnvdv 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 7zrvd -vjx1 /nspeed 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 verti h7vm7ul9 x0xbtu :ok b1v1*mt*bvz 8p. tx-rdcal 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 point is t tr1.*-9uuml7*vkbp0xx1x7zhv vdtb8b :mogiven by

  A stone, of mass m, is attachevim6s(n.x(mrgj w7y y w72sl6 d to a strong string and whirled in a vertical circle of radius r. Aty sj76ixv(yl 7 2(mnrw6mwsg. the exact bottom 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 experiences an acceleration of 4g when pulli eiy aooyxz m;.qwi7 0+ g9cqlwz/4.g4ng out of gmzec0.; .4ax4qwz9 q o/lyoi+g7wy ithe dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside verf4z-6 kf5r,8 dlpqacrtical loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of hisaprfl48 f56 crq,dk -z 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 ab+(jm0.6zgjlj w blac, out seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a verti jz+. g m(0aw6,cjlbljcal dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m ranh9 5gy 8cepp4dius horizontal curve with the tires on the verge of slipping 5nhgyppce489. 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 cqkw7ewx y:2pr (nhh- o.o4 0wvurve of radius 50 m with a speed of 20 m/s. The centripetal force provided by frictioh-4w0v27yoowxk.: hr n q(epwn 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 ao 6et + 2y)ylref:pp2dt a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to2l 2p)pr6f:toee +yy d make the turn?

  A car is moving with a constant4vu vl4s6z n)gqx-wx. speed v around a level curve. The coefficient of friction between-4)w.v4xg lvx uqs z6n 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?

  What minimum banking angle is required for an On m0mp9tc-xg2 lympic bobsled to negotiate a 100-m radius turn mgc 2t-9npmx0 at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a,/h2a:v o g b(nuywht) bobsled 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 m, banked at an angl;yvq m c r)cnom5se7)lx:-o4( ;wx uz3)il fbpe of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at9u dlhey x5:;3 2/nqfcxv7xvm $45^{\circ}$. 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 unisg 9ur0-lj f4sformly in a horizontal circle of radius 0.5su4r-j s0 fgl900
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 t-mvqz99,j*l+hn jw p-m arg-i/hl4bio a speed of 45 m/s im,j n4phq+ zwhvr9 g -j9iablml* --i/n 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 pro6 lt tkpmd*t0;.*m+r0ayrzrpton 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 standing on the Ea;y2f- nq ui/ u2ap5sgk+6ivdsrth, due to the gu2+fi ikan-65s;p2vu sqd/yMoon? 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 at.6+0w d1wv/vje qk5l v*hvnd ttractive force between two masses is F. If the masses are moved to half of their initial distance, what is the gravhtlvd.0jvk5*e 1q ww6+v/dv nitational attractive force?

  For a spacecraft going from the Earth toward the Sss-n mvmpt9 :6un, at what distance from the Earth will the gravitational forces due to t:6 nsm-mvs9 tphe 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 isadjh ;lu8,*b0z73xatvn 8m ja $7.4 \times 10^{22} \; kg$ 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 w i,x+9*kfefedistance above the Earth equal to the radiu,i xef+f9kwe*s of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface wp.rnuw btd h b3 )/ctr23qd6/qill the accelewqnp) trbh6/t d33q b2.dr/c uration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars ahd8 buf rh-04 bud:y bcod :lg4h*c6/at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the sb c :o acr0hu6/ul84 yddhdf:g*4bbh-atellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 140x3r kht6mwi)w1fb 8t)00 km from some planet's center, the acceleration of gravityt) f1h xm 6b8kw)3wtir 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 surfa ku ne*5-7d 4hwa+lbs ,b1dmvxce of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what i,hw-d vldabxsk*m47+ bu5 ne1s its weight?

  By how many newtons does the weight of a 100-kg person change when he goebyk4,hy-wo/ w s from sea level to an altitude of 5000 m? (The mean radius -ow by/kh w4y,of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r.fbf;nb8ibdi( hh+r6w jc w) +5 A satellite of mass 100 kg is at a point 3r above the Earthfwrc jhihid6f8bb+5w+bn ;( )'s surface. What is the satellite's weight?

  A spherically symmetric planet hass4ww l 5i ;s+fvb5a)iudca )e, four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would i;uw acs 55+)ifvlbesd4,)awit weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sytm6iw e2 s)a3un all lie on the same line, with the Earth between ts63a mwye2i) 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 ball is-;fr +is b4ia1p8;oix czpx2 z 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 circulax 1pmvtwv)9iz mft7 dmhlvoe0.7*k+/r orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of/zw7me7*+o v i)1 htdm0k vm9xpf.lvt the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth 7ndiqz 4ag0g6 (i.e., it just skims the surface of the Earth). How long does it gdi z a40qn76gtake 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 suk hho*-30x-pywejgj8 rface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earthw-h j8j-ox e0h3*gykp? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orb ycig3 ,2ysif+ 4yaid-6x 7w-4oibzvlital 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 srbp2 /.kfggo: t t66forbits 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 A7tuu2m 66to8 8gum9 cre6myc+fzn(uc has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. H 8ouecugtmm896cfur mc n(z26ty u 76+ow long does it take moon B to complete an orbit?

  The planet Jupiter i: z4-rqpuz* lbhzqo ,8s $7.78 \times 10^{11} \; m$ 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 i ;kqa:(.lnfrs s the average distance from Jupiter to the Sun? (The distance from thes:rf.qn l a(;k Earth to the Sun is $1.5 \times 10^{11} \; m$.)