Is it possible for an object movib +ee9kb:n)lsng with a constant speed to accelerate? Explain.nkb):ls 9e b+e

  Consider a particle moving with cop 6q t176t c,g 54fpeab 2apv+3yyui7lwyd*rlnstant speed such that its acceleration of constant , vq d5ryec7li42p*7tyt+gfaw 6bpa lp316 yumagnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compareaw43gv,)qerh /t ov;)yl qs 9y the direction of the object's velocity and acc/,agv4v tyyqw; 9o) )rlqeh3seleration vectors.

  When an object experiences uniform circular motion, the direction of the;fmh zqx9c ns/a:e y10vc,7wk accelerationsxnvma1fzh ,7 e9/ck yc :0q;w is

  Consider a particle moving with constant bk h/nn 7p;d8yspeed such that its acceleration of constant magnitude is always perpy;pn/bhd nk87 endicular to its velocity.

  What type of acceleration does an object moving with constant speed in b1 ut0qol l;ca*vro36a circular patlv*l6a 1 o;0u qrob3cth experience?

  What force is needed to make an object move in a cyh (,, s+ravxiircle?

  When an object experiences uniform circular motionzu6dv/ x4dq :m, the direction of the net force isq u4xdvmd6z:/

  A roller coaster car is on a track that forms a circular loop in thii *xvf optq;.iw29o -e vertical plane. If the car is to just maintain contact with track at the - p92wf*o ito.iviq;xtop 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 loo5+kn4(sedf -z) ictqfv j9g h7p (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 fog n 4ve i(f9kz 5fst+-cqhj)d7r its speed at that point?

  A pilot executes a vertical dive thenzr19 d9giapr;0 yp6v5depd n * follows a semi-circular arc until it is going straight up. Just; dd9nieayr15 p6 9d *z0gppvr as the plane is at its lowest 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 curv j/atjdq8ub0o:i(p(g e 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. Then it 0 4u9 j9fc8xwn2lpidwgoes around the same curve at half of the orid wxnc9w 2u 9if48jl0pginal speed. 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 radixa1s-4m uze, yus r at a constant speed v. Then it goes around a curve of radius1mxe sz4 uay-, 2r at 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 p3knd.nz5qk-l3 hev+of radius r with speed 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 from the road is equal in magnitude tvnq+-n p.e lkz3 53kdho

  Two horizontal curves on a bobw4 w-n; vm:mgfsled 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 curve is v. What is the safe speed on the larger radius f:v;4 mmwg-wncurve?

  The banking angle in a turn 4b.m 0xsd )tomon the Olympic bobsled track is not constant, 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. Wos )tmb0. xmd4hy do they do this?

  Is it possible for an object moving around a circular path to have both cel(gc irof7f;yc), g8xqhtc -0ntripetal and tangential accele xg7,oq;-t8fcl)hfc 0 yir (gcration?

  The gravitational force between two objects is pk r4xw1chv*bj /t3p 8eroportional to

  The gravitational force b,y/h 2xrdf2q-ll0gc +og*obm etween two objects is inversely proportional to

  Two objects attract each other gravitationally. If thevxb0m0 ,gy;cj distance between their centers is cut in half0 g;cb x0y,vjm, the gravitational force

  Two objects, with masshwzj(1s0 t mu9lw7uxi79 zk (ges $m_{1}$ 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.lyz:nq2:br6j8xfma dh5y( *)nup d 6mdyfj3 $m_{1}$ 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 univ)n;jsnzqi8o .vg+ z5 zersal gravitation.

  Compared to its mass on the Earth, the mass sje g;hb3:4nnof an object on the Moon is

  The acceleration of gravity on the Moon is one-si :1*hry m+y;8zfsx,8m pacqrd:* gw ohxth what it is on Earth. An ob, z8pq wyo1;frm* 8yscha:hdr m:+xg *ject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rock zba bd-*9c f)w46mlkaet's weight

  A spaceship is traveling to the Moon. At what point is it b qlav tu/w9y) gshg98)1tzs/qc-tdx2eyond the pull of Earth's 9-t))wx8tcdt uy// avhzqg lqg9s2s1 gravity?

  Suppose a satellite were orbiting the Earth just abojzgi,(f9 wrgcx32x1er:hxa/ve the surface. What is its centripetal acceleratigj3e2(wr af/9 x xhiz r:gx,1con?

  A hypothetical planet has a mass of half that of the Eaejpl*pj y1i*0rth and a radius of twice that of the Earth. What is the accele * *pliey0jjp1ration 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 whaukc:ut l y49 za,yf,c+t it is on Earth. The radius of th4kca ,t:f+,l u9zyyuc e 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 radiybfi bdjordy/* tk+ox (880z7us of planet A. If brd bo 0yk+d7i(8fy8* /ozxtjplanet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B hat/cg i-57he0* sjciowunfic:j l95z0s twice the mass of planet A. If planet A has radius r, what is thejfc 0c0 ew-/chui7 i*n o:9gjzstl5i5 radius of planet B?

  Consider a small satellite movincrk:c5 q93ab pg in a circular orbit (radius r) about a spherical planet (9 ar5: 3pqbkccmass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same b5uxc(qhoz/1wu (ye2*.nbw g orbit. Compare the two satellite's spee2w/e(qgn.5w1o(uuxz b hbc *yds.

  A person is standing on a scale in an elevator accelerating downward. Com p -yse3b.uxkutch ,)jx6l/6wpare the reading on the scale to the pec. k blwehy6uj3 -) xpsxu6t,/rson's true weight.

  Who was the first person to realize that the planwdtq.0he1b a/7px9r wml9 vb.ets move in elliptical paths around0b vaml.x9rpwe7d. thqw/ 9b1 the Sun?

  The speed of Halley's Comet, while o dnpfz,2td( wf1(m z7traveling in its elliptical orbit around the Su(od(n ,zfz2t wfdp 1m7n,

  Let the average orbital radius of a planet be R. Let the orbital pi4f c8egv.cxuorj 2v p33 /y)a,aobs3eriod be T. What quantity is constant for all p 3ja3.u8, /2eaovrxcp svfg4) 3iobyclanets orbiting the Sun?

  A planet is discoverep aegm:*jca569tpo c/+ *a8xc4 rwkted 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**/atm4orecp5pa98ckjwagxc + :6 et the Earth's orbital period?

  The average distance from the Earth to th:q/jw,lw 6b2qrgd;vn e Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What isqn,d 6:q/ jv; lrbw2gw the asteroid's average distance from the Sun?

State Kepler's laws.qfdmv ,p9uzxk;me6 m l cw/ ai /nfq97jcw2;;(

  List the four fundamental :9y 9gyikgdd17no91b1g czzwforces in nature.

  An object moves with a constant speed of 30 m/s on a circgx(tuu-2r-4-cm:py thpr nm 0 ular track of radius 150 m. What is the acceleration of the objectmc:xu4 p ptu-m(-yrrt-0g 2n h?

  The maximum speed around a level curvr/83 u uodijp( vcxw:3e is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors rerdu /3(c8x piv:3o uwjmain unchanged.)

  What is the centripetal acceleration of a poign; ro+1 ur wg;n 1f6zm6z3junnt on the perimeter of a bicycle wheel of diameter 70 cm when the bike ur;gjg wr6nz+n6;m13z o f1 unis moving 8.0 m/s?

  A point on a wheel rotatilc,6kqhaz65. cho- cjng at 5.00 rev/s is located 0.200 m from the axis. What is the centripaz6qk5c6-c. , hj ohlcetal acceleration?

  How many revolutions per minute must a circular, rotating space station of+*g(, mmpahda vy*, ec radius 1000 m rotate to v* ham(m*,dyeg pca,+produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes aroundyh6p7i(5 j:drcxuophioi 8 o- /kc74t a 13.7 m radius turn at 96.5 km/h. What is the cent ytp/7 4o8ciko5riu-j o: 7p(xhi6dhc ripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system/ t-eq6 opo4acpz4(z y is whirled in a horizontal circular path. If the myzocpqe-(p4/ a zto 46aximum 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 atu6 ostteqfh 6v; mnt1b.-2fo *tached to a strong string and whirled in a vertical 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 tho1tv ne u;h-os.tfm6b2t*f q6is point is given by

  A stone, of mass m, is attached to a strong string and whirled in,kd/i, o gh.ob+erc 8n a vertical circle of radius r. At the exact bottom of the path the nr i8edo ,.+hc,gbo/ktension 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 a g35wpi;e yle,cceleration of 4g when pulling out of the dive. What glwe,ipy; 3e5is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outsid p9mwn7 i7p8ake vertical loop (in which the center of the loop is beneath him) of radius 3200 m.7 k 9n8mppa7wi 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 weight. a vcj2izkg;b 2bi 9l c,:z:p2u What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolpk:vl2b; i,b2:zizc ugjc92aerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with the tiresa bkm,/03o18 a1pjj7ckjsy cr7gc:nv on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same :k b70 sonm7c1j8rygk1 jcpcj,aa3/v coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 )-g.c k ilam1w5-fuh). gu2pynl+ vlym with a speed of 20 m/s. The centripetal-v gl n2ykllgc..5 ) m)+ipauu1w-hyf force provided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of :pi( th+fr4uepnda5) radius 50 m at a speed of 14 m/s. What must be the minimump ut n hef5:i)(pr4d+a 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 aroundk6;zvb)k 2wmu7n n5 qh a level curve. The coefficient of friction between the tires ;5)7 k6buvmqwnkz2 hnand 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 rei-st9 bdbdjt0)cv 3)yquired for an Olympic bobsled to negotiate a 100-m radius turn at3)0 jytb)dv-sibc9 td 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a b+,iq /u.pjpgs 3mhw2r obsled 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 radiusq:.dqxr ; xrn,0ezi6s 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is ban mah7 9ae.b0rhked 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)/qbfs+ ah14, b4*bqslm spdw of a string is revolving uniformly in a horizontal circle of radq4h,a4*mb/ b1dsbpq ) ssf +lwius 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(f 5dty b7ars;1/3jinxqr vt: uniform rate to a :t(yir7;dt1sbqvf nax 5 j/3rspeed of 45 m/s in 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 protyby q h5zo)tan7)2h- y1e r. o7hbp4skon 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 standingxl(v -)2+xoj.raivo q on the Earth, due to the Moon? The mass of the Moonxv+vq( r-olx a.)i2jo 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 masses are mhf sq) p+j(tr0oved to half of their initial distance, what is the gravitational attractihq +ftr)p0js(ve force?

  For a spacecraft going from the Earth toward the Sun, at what d+67 bsa n:zc qx4+lsdlxw22t distance from the Earth will the gravitational forces due to the Sun a7 bc: x++ln 4qz2xal6d2ss dwtnd 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 is s(hfod/,to:l,c z 5 fo$7.4 \times 10^{22} \; kg$ 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 t.1jiraz f) z*ohe Earth equal to the radius of the Earth. What is her acceleration da iojfzz*1.r )ue to gravity?

  The radius of the Earth is R. At what distance above the Earth's surkpn:qoh sq///o 7 +ouwface will the acceleratio w/nu/ ph+/qo:osq7ok n of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface e.in5lsfyhbe:548 o uaf3z/ fcqual to 3 times the radius of Mars. T4 l5fn8 o5f/3z.s ybfhue ic:ahe acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km f vtm 9 -vokon(xm3)k ri6rf+6hrom some planet's center, the acceleration of gravity is rim- rxk9 3(okfnvot )h+6 6vm$32 \; m/s^2$. 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 Eaxw n0phbg b ;2b-yov8)rth. The Earth has radius r. If the object is raised to a height of 3r above the x b n0bo 2);pb-g8hvwyEarth's surface, what is its weight?

  By how many newtons does the weight of a ;l+ jmdiayp;28 t -e f-el.yjqo0x1dt100-kg person change when he goes from 0j2;-ltf ;-+odylqai1td 8.yj epxem sea 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 a point 3r ary6xw-cc 1jx3 bove the Earth's surface. Wrjx 1w6-y cxc3hat is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its r8pkkc4 v t*m8uadius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface pkm8cuk4t v*8 of this planet?

  During a lunar eclipse, the Moon,y+em/6onv t5s5niy y3 Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mass of+5 6ye5y3iomns /vtyn $7.36 \times 10^{22} \; kg$; 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 the Moon. rig h7ce-blhm6q 6wvo9.,tf8
(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 Earthm7 2 dceaz*pp5cyb0 b o0 so1xx32yz)a (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radiu3o1 bp2d opyx05z27by )xcc * masz0aes 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 skj ky h:e*b;4aq8 f3tpxims the surfx:ba*t e y4j;8 hq3kpface of the Earth). How long does it take 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 tju;p6:ea*iyi;km) v n6-nt +h m. kbovhe surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of t +n)ykm:bv6;i ;tm*pv6aju-in oe k .hhe Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter v56or( e3pku)b wvsao*rf a: 9of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupi;im(de( - mwxr1vl8)o cduly* ter orbits 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 A has orbita/ c3deg en b-/tc6y+nu5fo (knl radius r, and moon B has orbital radius 4r. Moon A takes 20 days to completnungc/e/(d+ eyt6o- 5c 3nkbfe one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter iuw. - k o+npb;md4m8qts $7.78 \times 10^{11} \; m$ 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 Jupit4ng, b bfm/l iftl*d./er 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The d4l*/lfg/m .t nb i,fdbistance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)