Is it possible for an object moving with a constantr*k,hqtxgc 6j*p: mtd)r6fe ( speed to accelerate? Explain.x, 6tfekmh6 crtd(q*gr :* )jp

  Consider a particle moving with constant speedrq2x6r )453xfm7d9nnrq2dm dpqk k l3 such that its acceleration of constant magnit5 3m2krpnqx3nd)qkm9 fxrd 27 6lrq4 dude is always perpendicular to its velocity.

  An object moves in a circular* ue jm:qsjc6n/1x4w dl0dpi. path at a constant speed. Compare the direction of the object's velocity and acceleration vectold:pudc6wsx1j.me * jin/q 04 rs.

  When an object experiences uniforw,+szh hw*(v4ip e sc,m circular motion, the direction of the acceleration svc ,iz+e*s 4( hwh,wpis

  Consider a particle moving with c9io ote8wnyd/v5vjt 5/ dap1n) 3 l9jdonstant speed such that its acceleration of constant magnitude is always perpendicular to its veloci3o vi5d)n 8p5/d avjo1l9dtyen w/tj9ty.

  What type of acceleration does an objectc /.tbqk :0pbq moving with constant speed in a circular path exper:pq0 /bbqct.k ience?

  What force is needed to make an objer:x1 lgbt n;.eq/ms :vct move in a circle?

  When an object experiences uniform circular motion, the directivn 66w2tw:a)u o7u9w3ort zm con of the net force iuow29v: 7cw)uawzmt ron366 ts

  A roller coaster car is on a track that form u;fz8km,kdf11xz6v p s a circular loop in the vertical plane. If the car is to just maintain cozmzk v6d,11pu xf8k;fntact 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 tiu:kgqlj3 nh)w-le; c7r:e/zhat forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact c-z3w)e 7n;ljik:ehruq/l :g 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 9e/7okmtrtm 6follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on h7mte r6 k/9otmim 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 rwvca87e s90i+kqq9 +hgsw w0sadius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of g2n. j /gpu( qinz 0816yihbodradius r at a constant speed v. Then 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, compared to the first time1q0hgu 6 nibpz i8(oyjdg2n./?

  A car goes around a curve of radiurn4hl j)b vq d7mew:67s r 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 fi4vdj:76 qew)rn7 b hmlrst?

  A car of mass m goes around a banked curve of radius r with speed v. If the j opjw1cz)0r0road is frictionless 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 jz)cw01rpjo 0equal in magnitude to

  Two horizontal curves on a)57 xdzs+sang n5dam9 bobsled run 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 c+5anxsmn)as 5 zdg7d9urve 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, bun.b,* r:-t;panedicyjr l2 v6 t increases upward from the horizontal. Coming around a turn, the bt-pjn ril;.n*e6yv ,c ar2db:obsled 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 both p;qm9 4j q6;odfhvsnbwm0 (f g,0coc t4:c. tscentripetal and tangentp4mosc:bv4wmo0 ns;tt; (6qjh .dqc 9cfg 0, fial acceleration?

  The gravitational force between two objectsu,84kmlt lz v- is proportional to

  The gravitational force between two objects is inversely pr b4(sepw+w-tm+ r4ha joportional to

  Two objects attract each other gravitatio,ny/h/nfs1 cm5 f3dp rnally. If the distance between their centers is cut in half, tc fr/nf5p,1s/ 3hdm ynhe gravitational force

  Two objects, with massenb9f/k)/wo4e)gdxf(sef-xv) y6 yr hs $m_{1}$ 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 vr 6nh8mu p;p8 )r2u yntexdx(4e8qr :$m_{1}$ 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 o (4h y0rw8wfxh2 c)pmcn/1pbbf universal gravitation.

  Compared to its mass ovje0stmf/8 sj 3(jx 6 thk/f2sn the Earth, the mass of an object on the Moon is

  The acceleration of gravity 6 ;r llnblo*u2on the Moon is one-sixth what it is on Earth. An object *ro2n ll6bl ;uof mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's suri vsu-k: g-blczg39,(g /uho rface, the rocket's weight

  A spaceship is traveling to the Moon. At what poiy- t0- 1tuluo3e)sl aint is it beyond the pull of Earel-t)y-ous i a tlu301th's gravity?

  Suppose a satellite were orbiting the Earth just above tha , el*l0cakv(e surface. What is its centripe aa,(l0l* vcektal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radibklft s2ht )yg 4c6e;nn;4q8pus of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, thg8pt;n4 ;6yh sqcle2)bk4ntf e acceleration due to gravity at the Earth?

  The acceleration of gra.jv 7(g7llx55m6fytoyn / iw kvity on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-f(/y7lf.l5 5n6mwgyik o7t vxjourth 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 rs3pii5 -nlrh)8 9fswvadius of planet A. Ifr 93 hs-vi85i)fpwlns planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, bnav ep-b -9wnk3p,4lrl, h03k(jggv eut planet B has twice the mass of planet A. If planet A has radius r, what is the radius of planet 3nke-pv0(g3jnw v lp9 lk,re hbga-4 ,B?

  Consider a small satellite moving in a circular orbit (radius r) about a spheric1bm v/0gh 6m p+sknlk:al planet (mass M). Which expression gives this /p+bmv lm6kh1s k: 0ngsatellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and ro 1rc1ifg,,2b- e p c/s3tavrzmtates in the same orbit. Compare the two satellite's speea3i mg b f1e,svt-r1czr/2p,c ds.

  A person is standing on a scalon/oi )rgsu :+e in an elevator accelerating downward. Compare the reading on the scale to the persono i:)sonru g+/'s true weight.

  Who was the first person to realize g1hxy;t zx2z1that the planets move in elliptical paths around t1yt;2g1 hxxz zhe Sun?

  The speed of Halley's Comet,+:sf rkgwkelwu -ub l.6oo 1dw-0y++)ib9nlv while traveling in its elliptical orbit around the Sufksv9 :0wgdiw1u o-lebwb .oy)k+n+ r l+l-6un,

  Let the average orbital radius of a planet be R. Let the orbital jdicc1.1jebum l bgj: ; 7outks*5-;bperiod be T. What quantity is constant for all plane t.s db1mjlk ; ubug;ci7j:*o5j-bc1ets orbiting the Sun?

  A planet is discovered to orbit around a star in th r tx5f6dl.wh9e galaxy Andromeda, with the same orbital diameter a 65trfx.l9hwd s 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 orbital period?

  The average distance from the E(g tmg.y) ucs.arth to the Sun is defined as one "astronomical unit" (AU). An astu.(ms .g)cgy teroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.jpty*er: ,f ; qo.fdy6

  List the four fundamental forces in amea9i yz hs2v-s+k 1t:m8;renature.

  An object moves with a constant speed of gkjimc9l7x4 m9q/r vk/e :-qt30 m/s on a circular track of radius 150 m. What is the acceleratix mekr99mckg:7j4- ql i /tq/von of the object?

  The maximum speed ar7hgym ,gmf:+. xbe8 cwound a level curve is 30.0 km/h. What is the maximum speed around a curve with twice tx.m fh, b8:e7gyw g+mche radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeteeui,j7nvpmgcblq69 ,3lf +k.r of a bicycle wheel of diameter69gj7 +u3mv.qlce blk,p ifn, 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis. Wha2mp be4 h bm3dh5/9mhnt is the centripetal accelerationbbm 2phm3 m d/h54enh9?

  How many revolutions per minute must a circular, o/ o *f*i9,pyr:lj pmqrotating space station of radius 1000 m rotate to prorp:9o opi,q*fm l/ jy*duce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes arou,fpl*jwxd w ;,0w 0nb6p.rjbfnd a 13.7 m radius turn at 96.5 km/h. Whaf*;bfnl p,0j.dbwpx0wjrw6 , t is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m sd02fmmr w+*-ikc 44lke,ex b mtring. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is e m-xir 4wl20bc kfed 4m+mk*,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 vekgn ,nr kiz(65rtical circle of radius r. At the exact top of the path the tension in the string is 3 z irn(,5kkn g6times the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, imuhv-+c55 v3u9qj8ztrc7dzw2 i) tpy s attached to a strong string and 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 stovzpyrwtcv 29 5izudj)3c785 + mq-uthne's speed at this point is given by

  A jet plane flying 600 m/s experiencea 0uvqw/ox2nru91uk: s an acceleration of 4g when pulling out of the dive. What is the radius of curvature 0quaw/vnu2orx:u k 19of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop/s32w/uxj / t nkm eas*whao95 is beneath him) of ra/*9xs/o5s2 at hjae3u/kmn ww dius 3200 m. At the top of his 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 about seven times his m e,e+c;y m7e.ux8iesweight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/y m+ u cei,x;e8ee7.mss?

  A car traveling 20 m/s ro(pj k si6w5mt4unds an 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 coeffikt5 wp(s4m6j icient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radrjd c:j 6l4a;xius 50 m with a speed of 20 m/s. The centripetal force prjr :a4dcxj;l6ovided 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. Wha nst7v.j+7g( otv4vr)1bls got must be the minimum coefficientr+ t1 l4vvbj s)7vs.no(7gog t 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 cc1jhew+bo5l z137-qx2ki jsfj j )yoi(1f 6fhurve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radik e ws)i5bfl1 2-h q1+j1zffo 6yc jj3jhxoi7(us of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negotiajupkvs , 9.hrghqhwk.- 929lhte a 100-m radius turn at 35 mqkuks 9hh jpwg 9,lh ..h-v92r/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run b *3rtaj3p,k fis 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 affzqeq)q .,*od 2rtv -uw(kk4ngle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked y 8,p9w ewu:t(vdvx1o 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 unifnq1b,d 3hg d..aqvv0b ormly in a horizontal circle of radius q, vgd .qv0an.bh1 b3d0.500
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 carzi;dy w9g4bj )0,cj mp accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (on9wcg0,d p)zmyjb ji 4;ly 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 pt uoz, x7kjyu/s3 )f6u,:fnucroton 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 fkeic* b(ian- v8t ,.m5qzmp0c 8fb9wyorce on a 70-kg person standing on the Earth, due to the Moon? The mass c(wnfpmta5e iv-b.q9ci 8mz 0ky*, 8bof 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 masses is F. If the me)vdb s42 trt;asses are moved to half of their initial distance, what is the gravitationa tte;4br2sdv) l attractive force?

  For a spacecraft going from the Earnfib0+ (u8ozb *nbf0sth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and t+nb fu0s*bbn(0oz8 if he 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 isg(,ce gdjf:3lgw. l ima*6:mb $7.4 \times 10^{22} \; kg$ 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 equ 7ulw5f;twc+lal to the 5lulfw w+ tc;7radius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At ,h. (o :o9oqxyzx vi8twhat distance above the Earth's surface will the acceleration ofo(x8vih yz, to9xqo.: gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal tp 1 ) .*;tsfct+sgmvlio 3 times the radius of Mars. The acceleration of gravity of vcps*1.tsglmt;i+) f the satellite, 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 accelerr: uctk*5jhx-ation of gravity hj-:x*r uc5tkis $32 \; m/s^2$. 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. Thu.7,n ihmfq7uorj- + se Earth has radius r. If the object is raised to a height of 3r above the Earth u .7nosri-fq m7,uhj+'s surface, what is its weight?

  By how many newtons does the weight of a 100-kg pom)dj3vhz o7d2 s8jz*erson change when he goes from sea level to an osz *jv)h73z82ojm dd 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 a point 3r ab)r. za rutryyxr:x7f 9h*0q0f ove the Earth's surface. What is the satellite's weight?xf*q)yz9x:7y.frrrhr t ua00

  A spherically symmetric planet has four times the Earth'/6vht dtiavn 89( 3rmkbei1 i)st6wx8s mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much w 68 8inv3vkeaxbt(wtsi6rtm dih 1/9) ould it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun al y8xux3eik .wyn,2bt5 l lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mas,.ny82tky5 x xwe3b ius 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 tranr qz3c8l ;3pgcsported 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.1u8xbe 6d:apge., it just skims the surface of the Earth). What6 1g8apb :duex 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 circu6)q-e w/d+q 6vqezhoo lar orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? ( qev-qe +qo6wd/oz6) hThe mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circubm8c2i s-z .vglar orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. 2-giscv z.8bm What is the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diame0w;dilq 5ux(rb7 x7ubter 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 radius of wx3 ytxl hy 8b1kie-*y-5ms/i$422 \times 10^{3} \; km$ 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 radiuq2x :r5+uzm. - m7 8hlwdggjhzs r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one or5ljw2r+ -m:7d.hxmuqzg h g8z bit. How long does it take moon B to complete an orbit?

  The planet Jupiter ixzip g)7fs76l s $7.78 \times 10^{11} \; m$ 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 c-mebd*)s)6) ,rbc irpukmku5 f+ y,x Jupiter 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Eamue)-pi ,6sxd))k+ ,kb rrfccm* u5byrth to the Sun is $1.5 \times 10^{11} \; m$.)