Is it possible for an object moving with a constant so5omun)k + stix) g13dpeed to accelerate? Explain.minok d+)xts )g153 uo

  Consider a particle moving with constant speedo re :k9)cs ew8/tldc8 such that its acceleration of constant magnitude is always perpendiculwd)rc l8se 9ko8/tc:e ar to its velocity.

  An object moves in a circular path at a constant speed. Comaksksfys+(g9 2zu., t4f f /por8smz9pare the direction of the object's velocity anary/ k9omzf.s us k+z 489tsf2g(s f,pd acceleration vectors.

  When an object experiences uniform circular motion, the direction ofbz 5 5f **cg7ynd xon-fr6h0. )vinpwx the acceleraw hyn ) 5*xbnvi6xdo-0 fn rc.pzg57f*tion is

  Consider a particle moving with const u,fs3gsmenha xdum/,0*hgco*g 2u2, p y10gy ant speed such that its acceleration of constant magnitude is always perpendicular to its gy10, gsax*gfe sy pcmh,h2n o/ md g*u2,u30uvelocity.

  What type of acceleration does an object moving with constant* )j)owqj:o8.qu;kjr my :mix speed in a circular path e y;oq:j*)ri8)okx.u q: jmjmwxperience?

  What force is needed to make an object move in a cixv4eid,l zre/-n:8yd rcle?

  When an object experiences uniform hks :me6 t7t..xz jdq52g+.hu dq(gjtcircular motion, the direction of the net force s +5ku6 qm.7hztx.qd:ejtg(t.d2 jh gis

  A roller coaster car is on a track that formp/. y-atx2fye;,vy c qm9cup mc*w(2ms a circular loop in the vertical plane. 2(.9cmt/ m w yxy,uayc 2-qfmpv*p;e cIf the car is to just maintain 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 cixvq/arp)2t zl//-vr lrcular loop (radius = r) in the 2alp /rrx//lzv)- qvt 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 dive then follows a ;slg 4feg7s4am he61 fsemi-circular arc until it is goi;s74h ls4me 1 gaffg6eng straight up. Just 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 cvn 2,1d f+yesj)tfg7n urve 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 o7o/gq6 /we7n cdqlsq **wst9 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, com6o/qt*77lw9q /sdo qe s*wngc pared to the first time?

  A car goes around a curvexsh 5m8kmvk0y3i2xu* 8g 5dyp of radius r at a constant speed v. Then it goes around a curve ofmgyu052smvk5 d* 3yp8h x i8kx radius 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 c) lch6(e4,p nqf yrlr4:tbv8 of radius r with speed v. If the road is frictionless due to ice, c) c:te 4vrylq46r, hlb(p8nf 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 to

  Two horizontal curves on a bobsled run are ban2ka,9i k5;bpo ;kg5yg5a9 9zqm(qzr8 sjw p dgked 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 v5 zqiwam ;b9ggarpy58j(k2,ks5 k9qdp zgo;9 . What is the safe speed on the larger radius curve?

  The banking angle in a turn onqctf, /vh+k4 e the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intent4he q f,ck/+vtionally "climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an obmyz t-t zeab+e4b l+2a7 :j9woi1mgg0ject moving around a circular path to have both centripetal and tangential accelerat4t 90by 7 m za:j++ geeio1atz2-gwbmlion?

  The gravitational force between two s 0jfr:wf.kf 6objects is proportional to

  The gravitational force between two objects is inversely proportional9;ey1exvvqc 1 vtpkr .hom-,; to

  Two objects attract each other gravitationally. If the distxvc-o 178yon(-z beypance between their centers is cut in ozvxop(1n--y 8ybe c7half, the gravitational force

  Two objects, with masse r:p3us qdq-bsvq w-9*s $m_{1}$ 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 ma. kzd1)dsw( xcgvrn d+1-w/rb ji2tc( sses $m_{1}$ 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 unkzu yq7o9l.* vcf m,3g1 br5vtiversal gravitation.

  Compared to its mass on the Earth, the mass of an;/e d+upj9jps object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An m mlnk .)b mys589, le;4aawdzobjectw .kby n9es;aa ,m8)mm4ldz 5l 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 rsz3dx p)h0( k 9royi3hvg :we(ocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull of 9xgo(5 b6j ckvj5rv)sEarth's j sk5gj9)6 v vx(5cbrogravity?

  Suppose a satellite were orbiting the Earth just above the surface. Wy2l9 p+: sq z9d,elcezraf l51mdek6(hat is its centripetal acce qek(lszem9a5dlzdfr2:p lec +,y16 9leration?

  A hypothetical planet has a mass of half that of8wxdyndq+ t1kue5ax u*+y (o 7 the Earth and a radius of twice that of the Earth. What is the acceleration due to gravi1qon7*u ku(dd+ea xt5w xy y+8ty on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of grav (u5pd7gb 8c+w ped+fyity on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moond58 ep+cy7d b(pf+ wug's mass compared to the Earth's?

  Two planets have the m axuu8i o6ckf09ob 441srg*csame surface gravity, but planet B has twice the radius of planet A. If planet A has m f 4i*am4ccuro1b9 6skx0uo8gass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twickfg;al3/q o 8 5za vgig+7c:kze the mass of planet A. /gfkqvgac83lk z;:i7 5ga z+o If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radit 5v8iy fpu-93 p3uzwl )h3jyhus r) about a spherical planet (mass M). Which exyvljy z hiw359uf-83t)p3 hpu pression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same ouxo7eqs1 k(kx enq095 rbit. Compare the two satelliteoxu0e q7(qx1kkn e5s 9's speeds.

  A person is standing on a scale in an elevator accelerating downward/ u)ky ab xe.(0+fsxmsh d8v/n. Compare the reading on the scale to thexnm(fv bds/x0e 8).su+ /hkay person's true weight.

  Who was the first person to realize that the planets moveu0et 7umzme i5q (kxue40(5qx6qjc 8o in elliptical paths around (qz mi j6x uuq0m54 0t cexe8o(7kq5uethe Sun?

  The speed of Halley's Comet, while traveling in its elliptic x4,csk5 x8su :t m((smrjt0paal orbit around the Ssmj :r xtsc0t(m,ux(4psa 8 k5un,

  Let the average orbital radius of a planet be R. Let thy )(jg3)vv r8cyu1y ey9w7y ode orbital period be T. What quantity is constant 9yr8ye )yc y7yjvw u1 )(dv3ogfor all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxg).ui2rcdx o-8*y rth y 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 o -td2)8ry *uxhg.ric period of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance bcdccl-6+bkl s uo:.0from the Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distak cu+cb b.co0l-:dsl6nce from the Sun?

State Kepler's laws.vzpn8 a. m,cu()lmk l505szxv

  List the four fundamental forces iczy 8e3k,ycnn8- e*eg n nature.

  An object moves with a constaqm07 /kg3j yusx n6yy*cfnl /:nt speed of 30 m/s on a circular track of radius 150 m. What is thnx6mf lnyuy7 /s 3j :0kyg/cq*e acceleration of the object?

  The maximum speed around a level curve ipl9 f-d d/iws0 )6kvfqs 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other ffv k-f) s0d/ w9qdip6lactors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bybakfor -. m76b. 7;vnokw hk(icycle wheel of diameter 70 cm when tono6 ba.(b ;ykw77fr-k kvmh .he 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. Whamm5t0ui jzydux61o k)8 1e.wip-zpe0t is t) y1. 5umpiz-xw 1om8kezdjpe0ti6u0he centripetal acceleration?

  How many revolutions per minute must a circular, r41pw( hdy xc-4 y e0*fw,xrguootating space station of radius 1000 m rotate to prox*yg yfcww 4(p4 xedru- 0h,o1duce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass ofscrc.r(d upj026k r fl(sw*9 b 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. c0rc .(slw2s 9r6ju*dp(fkb r What is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whirled inb1b lup42t rhr/h ihm+r(,0in a horiz hnm4,ul (0i1 rrh+pi/rb 2htbontal 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 not to break?

  A stone, of mass m, isl isifc2;gt7jodrh)c ,+ m ;q/ attached to a strong string and whirled in a vertical circle of radius r. At the exact to;oitmr,7qcj+gi / s2;fcd l h)p 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 stron42 zjwejj +pjbo q g/,)v/j*ezg 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 stone's speev/ e2wj)bo, j4z* je +/qjgzpjd at this point is given by

  A jet plane flying 600 m/s experiences angg y.cxm8c cqo1 l,a(5 acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is fly5.cyc a,g 1 moxc8qgl(ing?

  A pilot makes an outsid nsk;ps/p b(r)e vertical loop (in which the center of the loop is beneath him) of radius 3200 m. At tb/;()s psnkrp he 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 pilkuw/ +cg,g) 0s81 1kbmv d:zigsqi )xdot can stand is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at amd1 b)k) wqgg10+d k,sv:g8ic/isz x u speed of 250 m/s?

  A car traveling 20 m/s rounds an k8/ jjk l )-f3wede; bcnj1q2y80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second cu/ ;wqf2j3b k-keeyc8jd jl1 n)rve 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. Th:ri exwmns0, ai,5at(w ;9zbr e centripetal force provided by friction is sw ximir,5z:,0t 9nare(wa ;b $1.2 \times 10^{4} \; N$. 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 musl4 4b8zhg6r ww+, 9jyf//nkj- pln lhwt be the minimum coefficient of friction between the tires r6k/lhn/w f48z ljg+9hlyp, w4nb w-jand the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefficiento1xpu**m m d q)im/l3f of friction bex*mlpm)*3 d/1 mfqui otween 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 re: lgp,eprhgy8md mn52 zgm;9:quired for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s withoug2 ry,d lhenzgm:g 8:p;9 mmp5t skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at adj8ctfo a: ((p $45^{\circ}$ 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 dqrqnw1, g 1:xm, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank(nj1:8sp zfazma( f4sed 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 in a horizozi(6o*r 1i5-uaer /n6,op yo w dnp:runtal circle of radius 0.500 d* z ,oo: rr6-py5/ 6eupwia (o1unnri
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 to( :2itnsnj0yf a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical 2n(tsnjif 0 :yvalue 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 massmi; tu8w;a gs5 $1.67 \times 10^{-27} \; kg$ 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 ona 24tkm5cgz x3ifod0-az s8 4jey f/(y a 70-kg person standing on the Earth, due to the Moon? The mass of the Moonm3 /x5j2ig4yk soa8(ctz0zy-dafe f 4 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 yaytic9h l2ek, 6 92edsg7uz 1 1ye6bcis F. If the masses are moved1e k 19u6cbiay2, lh9ey2s7 zt6eg ycd to half of their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth to xd;dnj *;qt1cward the Sun, at what distance from the Earth will the gravitati1q;c; d d*xjntonal 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 Moon c3zko 3 cp*vl zsx4q/: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 "spamx*gq bf n3 g3wi:(b;cc si1+fhfr f0(ce-walk" at a distance above the Earth equal to the radius of the Earth. What is w;fbrigi13 x3gf*nf:hm 0(qfc(+ bscher acceleration due to gravity?

  The radius of the Earth is R. At ew.zg2 54hskl w g4)agwhat distance above the Earth's surface will the acceleration of gravity be h s4wz2g.)wegl g5k4a $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal t4fx( t ore cgu1lk .,,knf1jf9o 3 times the radius of Mars. The acceleration of gravity of the satellite, as eulfjc. 49ff1o ,1xn(ktg k ,rcompared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's cente 73i,*mhrafq dr, the acceleration of gravity is qidr 7am3*,h f$32 \; m/s^2$. 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 radiuso8,nu q gy2*jv r. If the object is raised to a height of 3r above the Earth's surface, whg2,jyun8v * qoat is its weight?

  By how many newtons does the weigsoj0i-v/*y 73pv5dnea-e d wrht of a 100-kg person change when he goes from sea level to an altitude of 5003vw oeprd*ijv /e-s57 y 0and-0 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 above the yk) x5k zz,2klwhoq9( Earth's surface. What is the satellite's weig9kl)w 5k (zzk,2xohyqht?

  A spherically symmetric planet cgjj8 e7/fl)k has four times the Earth's mass and twice its radius. If a jar of peanut butterjkfc)jle7 g/8 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 oct6mtt+5 k41v42ttk hei,gk Sun all lie on the same line, with the Earth between the Moon and the Sun. ce4g65 kk tt,4im 1tot2h tkv+ 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 tq9ug. 3 t7hw.y/3dh9jwfn g lmransported 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.e., ieowbe pu55th9t:. j:;z :f bqbt just skims the surface of the Eartzf9qep5e :j uohb.b;tb5:w :th). What is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a lowd ):ra5 lqr/ksy4i 0 +hmktyz6 circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take tor)0y6/ks l5:khzadt+4m q iyr make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circula0r)cts5i/- v zku3jzsnu p03eoa 1wo. r orbit 230 km above the surface of the Earth. It is obsewn315zu r)ikp .sj v00asoc-te3o/uzrved to have a period of 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 Jupiterb5xjj( zsbs6 ,zsn:0y(m -f7rgntbi*, 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 p(- 5bhsr:mfs*rtt- wvlanet 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 j5bwqrsxj;7)6 -yue2i gk:z unearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one:;7-wqkue sx6zb jyurgi) j25 orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is wd8e6izy)0 mo$7.78 \times 10^{11} \; m$ 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 year8ao: tz :xqxmyt w,r,(s to orbit the Sun once. What is the average distance from Jupiter to txqo,r,8t (t:z m:xwayhe Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)