Is it possible for an objt*); n 8rlymue6 kvok,ect moving with a constant speed to accelerate? Explain)l 6 *k,8ekmy vrutn;o.

  Consider a particle moving wpu ww0*psg- /iith constant speed such that its acceleration of constant magnitude is always perpendicular to its*-iwgspw u /0p velocity.

  An object moves in a circular path at a cowswm3un: + ;s z dd6:u65kdixanstant speed. Compare the direction of the object's velocity and +: s;wzm das5k6dudwu6x:ni3 acceleration vectors.

  When an object experiences uniform circular motion, the direction of t8 ahah*4dy8z 326aa j wxg dra6e:/nfvhe accelerfh/awd:v84h 68xj6 za aegdar23*ny aation is

  Consider a particle moving 781jz ml.kscmwith constant speed such that its acceleration of constant magnitudeks1m7.l8 mz cj is always perpendicular to its velocity.

  What type of acceleration does an objw omtg*m),ws9xx4q z,ect moving with constant speed in a circular pat xt, s,)xq94z*gwwm omh experience?

  What force is needed to mf s+j- -a5 l0lcqn:1 .lm oxdj)6/fy -vhefqtdake an object move in a circle?

  When an object experie pzac/x;jv)9mp;id g( nces uniform circular motion, the direction of the net forcm)9;pdpa / zjcgv(x; ie is

  A roller coaster car is on a track thatfoq6x/fg( 7y n forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top (y/6q7fo fnxg 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 form8ed d(m x ,t5t1em0cpqw 7g1obs a circular loop (radius = 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 itwe cq10m 7 e,do1(dgt pb8txm5s speed at that point?

  A pilot executes a vertical dive then follows a semi-circulalm9vy,mdf z;1 r arc until it is going straight up. Just as the plane is at its lowest point, the force on him is19 y;lfmvm ,dz

  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 radiusk e)4gvj )4kql $r$ 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 constajuow *du6+b1d0pe vv+nt speed v. Then it goes around the same curve at half of the original speed1uov*+ 6wp d 0v+bejud. What is the centripetal 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. Thens 3+.-ov2 chk4+ihqsezwu q. z 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 firsqk ziz.3vuc2+esw s-qh+ 4ho. t?

  A car of mass m goes around a banked curve of radius r with speed p or3;cyc )im .p;kod*c0dv*1pzu4vn v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car f rmd.*z4vcp3) udvop; ; op c0ink*yc1rom the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, but on;*6g-av f- w b;omkrike 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. k ;-bv*g i-oarmfk;w 6 What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic boo5 s)rnv9l6s fbsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsosfl)rn 6v 5s9led 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 movinsr7ima h5- iaro f. .:r70emdgg around a circular path to have both centripetal and tangential a75dmhim7aas-err fi. .0 r:gocceleration?

  The gravitational force between two:4b/ge80qknctq l6+ 9 dezdzj objects is proportional to

  The gravitational force between two objects is int lg64rd7vo7b) gvrf( versely proportional to

  Two objects attract each other grmjn48 uyc+a 9njg65rravitationally. If the distance between their centers is cut in half, the gr956rnjnyg j c+4 am8uravitational force

  Two objects, with malth7/4x imfw)sses $m_{1}$ 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 massei iz.-8gqrr*u; vuw y 7u,tj7ls $m_{1}$ 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 graym-u7lg7dg+q 2szq-u vitation.

  Compared to its mass on the Earth, the mass ofpzc8g)7zhw *8u8bim8 u apbt7 h4* gtj an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on E-lbrvv //7 kurwv+tf.arth. An object of mas l/v+v/brv. ut r7wk-fs
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket'd5*ant27 n6v wvho,nvs weight

  A spaceship is traveling to the Moos ,s h2t ml(s7sdqwu*(n. At what point is it beyond the pull of Earth' q(wsds7t(mu ,h2 sl*ss gravity?

  Suppose a satellite were orbiting the Ear+nvs04-nf dkfzi x16cth just above the surface. What is its centripetal acceleration?-nv01nfs fd4z +xk6c i

  A hypothetical planet has a mass of half that of t2(cv8i ush2mnt+9 fi nhe 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 +musi f(ci hn2n9v8t 2gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth fafuk5.h*w/k . The radius of the Moon is one-fourth tf *kh5w.ak /fuhat 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 twiczi q6l g+,w2d2bgs/fv e the radius of planet A. If planet A has mass m, what is the2wb2sgz iv,d qgfl/6 + mass of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass of pl+8-souz6x hp qanet A. If planet A has radius r, what is the radius of planet B?8+o u-hsx6pzq

  Consider a small satellite moving in a circular orb8ybtm3/des 8)ksel05o l h 1gd- jcej;it (radius r) about a spherical planet h8bjys-8lkmls0 3d gd/jetce)o51 ;e (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. ;j2 ;hqr turtx) )(y3kmhny5y Coyr;;uh)x jy h3m2(5tytq )knr mpare the two satellite's speeds.

  A person is standing on a scale in an elez3 8 q jjr*2k+ohuy,ac vcu)l/vator accelerating downward. Compare the reading on)/y o q,u8aj+ khzr culvj*c23 the scale to the person's true weight.

  Who was the first person to realize tha68j5seha ec*i t the planets move in elliptical paths around the icaj 5he86es *Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit aro0d( rcaw ndi*e5 nc+3ound the Sun0d( 3rinwncoc*5a d +e,

  Let the average orbital radius of a planet be R. Let the orbital period be T.*vy1lptikl1uz4qx;uz8 i+e1i vk d5/ What quai4;qz y1lt dx58pu kv+vzlk u i/ei*11ntity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the*7agv ty/o14 aizow9sx mn0i9 galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If mzio 4xaniaw7 yo gs t0*991v/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 Earth to the Sun is definslzqf b m77r2w ai/u2:ed as one "astronomical unit" (AU). An asteroid orbits the Sunqa /s77b:murf 2 zli2w in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.gf y9c,r vq:yv4ob6r ;lz78zk

  List the four fundamental forces in natu:w(rl6ztiz1pu nj 6h//zb3 u ure.

  An object moves with a constant speed of 30 m/s on a circular track of r-d(0xf9dl;u sm egh8dadius 150 m. What is thexf-h e(0;d ls 8gmd9du acceleration of the object?

  The maximum speed around a leveluek7i nwd 2* b2.h kk9khclk:2 curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume allb9kh:u*kc2hle27 k.k ik2w nd other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle a f*cg+ lf)u+zvvq o+ycv8- +dwheel of diameter 70 cm when theyf++vouvaqdf z l+*)ccg +-8v bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 o. 6, omh8n;e7-rwyi34lh:imb y ltqom from the axis. What is the centripel.irmobn- qo:i ;hwl,h6yomy 473 8 tetal acceleration?

  How many revolutions per minute must a circular, rotating space station ofcl ;/d e tsyud:q(4jn. radius 1000 md:(c/n ly qe.dj tsu;4 rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at 9 y:ilx9y0vy a0h hm)b:6.5 km/h. What is the cex v0 : hym)0b9yahliy:ntripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The sysjz (xhh/8pw/tfw v c81tem is whirled in a horizontal circular 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 f/(wzh /vt81j8w pc xhnot to break?

  A stone, of mass m, is attached to a strong string and whirled in a verticw4 g0q:3h htoqtt;ccxi)8f t)al circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The stotq 4) 3q) o8ghixc:c;ttw0th fne's speed at this point is given by

  A stone, of mass m, is attached to a stn3gbth 9y43s l.kdcp(rong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the stringd9y.n(t34 pg bscl3h k 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 accelege z+5i z4-ye2udiq (fration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is iez -eu 2(4df+zi5q ygflying?

  A pilot makes an outside vertical loop (in which the center of the loop isbkic 08b- wc8a beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat with only one-half of h cwc-ik8bb08ais normal weight. How fast is he going?

  The maximum force a pilot can stand is about seven times his weight. What is t jb6n)j 9d8rcrhe minimum radius of curvature that a jet plane's pilo6djb cn r8r9j)t, 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 curve with the tir9r3r x9f g8bmpn*7wvh dd(yg pq7ed o 48m;m+jes on the verge of slipping. How fast can this x*bw +hqp(8dg 38gpfrd9n 9omrme4y7 jd7vm; 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 curve of radius 50 m with a speed of 20 m/s. The cenv-4utwv:pbg 1tripetal force provided by tw 4:vbvu 1-gpfriction 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. What must b,5mnpdm: dkg6 cxhr9 :ur1so4e the minimum coefficient of friction between the tires and the road for the : 9hsr:r5p4udo,m 1m kndxgc6 car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefficientdp+nb na :lg;c* k(i1e of friction between the tires and the road is 0.40. What is the minimum r nc; aepkd*:b+1lg(inadius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobson dpl1+m a3(yled to negotiate a 100-m radius tur3on pm (yd1la+n at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is/r28krayssv0 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, banked5/ynd9h84gzm vnp 4qq at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is nv c4fa,j;)sfuqa4pz- q2nqes )u7 1zbanked 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 inlt6f7ftq1 s b+t:br;n a horizontal circle of radiub1bf7t: qtfstrln; +6s 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 accelerates5 k( qyh di5ow*)1yes)n 6frtd at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (o)dieqyr6 t on5sh(5)1yfk*dw nly 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 aclr a -l2jm;s/6zhwi/66dl k proton 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 Earth, due t53ule cc8x5sf8,ll q do the Moon? The mass ofcdxlc83 se8qflu5 , l5 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 betweer2(n*n34mnercw jo -j n two masses is F. If the masses are moved to half of their initial distance, what is the g jrc nrn4w2o*(j-m3ne ravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from tt k4 mhcdzlw f0t/45/a .jie9ehe Earth will the gravitational forces ae0j95/t m/d44e kzcwht i l.fdue 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 ii5wbpb: 7j;agw jm(t2s $7.4 \times 10^{22} \; kg$ 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 9yr)qnz. gvcx)b.,q+bca7x wp6l(bj; mr3 kba "space-walk" at a distance above the Earth equal to the radius of the Earth. What is her accelerationkb)lx qc36,b.x7z;jrb.yb r9v ca w(+qm) ngp due to gravity?

  The radius of the Earth is R. At what distance above the Earth';s3h;xjp y2ag-8 (gcqrl7 ;ka /flwg fs surface will the acceleration of gr hlkxgj3afywr s /lq-g(f;c;; a 87p2gavity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distayh,7 nqyujj6+ ild. k(ti)3 hlnce above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acc67,h3u(j l.inlj+ythik )dqyeleration of gravity on the surface of Mars, is

  At a distance of 14000 km from tf2(9/zhn:+ qbmvrvzsome planet's center, the acceleration of gravity ih tmfr z/: vn2b+9z(qvs $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surface yt;;( ln ibhr(1p3vngof the Earth. The Earth has radius r. If the object is raised to a height of 3r above the g(rby; ptvhnn1li(;3 Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person changem:rrtjg c( a-ez ,d3b6 when he goes from sea level to an altitude of 5000 m? (The mean radius orzj r ,3tg-bdm:( cae6f the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg igo;whgl,( jkg:a c .,ls at a point 3r above the Earth's surface. What is ta c.j ,k;lghl(ggo,:whe satellite's weight?

  A spherically symmetric planet has fo2eviln 4w+-i5m gqf 2 4kry4fwur times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N oi vgn 2ff5rq2w+i4wym kl 4-4en the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon-ic,pjpds5ijp n6s;08;q i1fkus nb., Earth, and Sun all lie on the same line, with the Earth betb1 6i s,f;j pc qd ji;5.-pispk0sn8nuween 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 tran4a 1 yecw0py7vsported 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 abou(x9*pks3mm vz ,y*vydt the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radiussy 93(kdpm x**y,vz mv of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circum (3r)svzs,o-u3gr mpv umss7a 7+3 dular 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 sapu3+rmvmro ( 7)3d uu,vsss- 7zg3m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the sud 79 jjn:yhl)+22okyi ;irugbrface of the Earth. It is observed to have a period of 89 min y:+)9 jbgi7 2jl ;dou2yirkhn. 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 orbit /y zs)9.vktubpg+ lc)al 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/icp/vo 0tv0gdr: 5c n.qx5gw 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 inbl 22qihe66e m nearly circular orbits. Moon A has orbital radius r,ebql6mihe6 2 2 and moon B has 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 isrn37-,(mj-bbh ggot4 mz b(hm $7.78 \times 10^{11} \; m$ 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. Wh-j1 :cpx, pw3c5p) kgo4jfy97nbyfdkat is the average distance from Jupiter to the Sun? (The distw9 j)fppog, jx 1ykdn 4b 5c:pk37cfy-ance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)