Is it possible for an object moving with a constan6xm w e8(6pckot speed to accelerate? Explain.x8po6( kw6c me

  Consider a particle moving with constant speed such that its acceler02adhg:xbmx6q c 2n*kation of constan da20hbx gkn2x*:m6 cqt magnitude is always perpendicular to its velocity.

  An object moves in a cix z/5w8hw)qie9yp;ygrcular path at a constant speed. Compare the direction of the object's veqy8whpge xy9 i)/z;5wlocity and acceleration vectors.

  When an object experiences, 2 gz7uvtnm :25ul see.ic7wo uniform circular motion, the direction of the acceleratiogw 2en2oemu,u75 ivz t7s.c: ln is

  Consider a particle moving with constant speed such that its acceleration oaomgba)sb fa 99/:v a4f constant magnitude is always perpendicular tov aabbasmg:f9 a94) /o its velocity.

  What type of acceleration does an object moving, w)hs8a9enr upoe1 d* with constant speed in a circular pa*a)dhue9p 8o s r,1enwth experience?

  What force is needed to make an object move in aarg qlit526smmc)lq(q77 t,f 2hz/jl circle?

  When an object experiences uniform circ/ va;*x7w ab t3iqnjj7ular motion, the direction of the net for*vwxj nabit7q/ 3ja; 7ce is

  A roller coaster car is on a track that forms a circular lui gk- ap27xa 55zm8.tpbk6rbpejldh /f-3 ;moop in the vertical plane. If the car is to just ma5 e-t ;7bpp6agku 8alpmjbhm/- d2 3zfikx5.rintain 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 (radop +hnndwf a ea 3;v24c7)wmr8ius = r) in the vertcd+hap7ao wwme82vn 3)n4fr;ical 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 verpkz5b-n1 -7mzbsu y/m tical dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest ps mpz -y/bzkbum75n -1oint, 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 curve of radius ik b7,wq53 lfi,m xazt+:e -dt$r$ 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 p;/f80yuu j ryspeed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as it r8j/0;fuyypu 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. Then it go/ut):u;c hmx zes around a curve of radiu)utx;m /hcuz:s 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 cawd c/+.)n5*bw/c imz qkao-g urve of radius r with speed v. If the road is frictionless due to ice, the caq//do c wibnzkc* a-+.m g5)war 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 a27e;aq3 iuo zj bobsled run are banked at the same angle, but one has twice the radius of the other. The safe spe3j;uize 7q ao2ed (no friction needed to stay on the run) for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track a q;aehd7,sbzf 5k97eis not constant, but increases upward from the horizontal. Comia5;es azekh dq779,f bng around a turn, the bobsled 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 : -w uf8jt03 .zwcdot yfm/ur9both centripetal andu 3t0zuof:mwfc 8ryt./ -j w9d tangential acceleration?

  The gravitational force between two gdh zm/dik8 h-q7i1. bobjects is proportional to

  The gravitational force j7mxul.ypq 2-between two objects is inversely proportional to

  Two objects attract each other gravitationally. If the digh7w84g)fv ufda; 3 6x j/zr6gfxto6mstance between their centers is cut iufgg676af)tr/v xjoh64wm; f8gxzd 3n half, the gravitational force

  Two objects, with masses cp,mvxw* :3 rf$m_{1}$ 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 massevtskk hx*:je4 ( b34jjs $m_{1}$ 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 universa 1h6 wcss ,o r;i53ljhx wkq-kdy*w*h6l gravitation.

  Compared to its mass on the E 0 qfc1 :w/2vf,dent-acq6 gxoarth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth wk z78iih v5xb,hat it is on Earth. An objxi k i8b5v7,zhect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sur:awf:e 2r(;aef (r yjaface, the rocket's weight

  A spaceship is traveling to the Moon. At what point ie: p eao5jfco1ty r :3d ad913 (u.ial(xjn+gws it beyond the pull of Earth's re t(fd3jao.l xip 1 ge95o+ ywj:1cdnau(:a3gravity?

  Suppose a satellite were orbiting the Earth just above the surface. Wwr/usboe1:wz kl1 ;0 p.e74cqwd 8u iwhat is its centripetal accelerat.dz /4ep1 b 1l:u0w8uiq sw 7e;wkwocrion?

  A hypothetical planet has az+jt77en;ccb; -t m na mass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravit+7cje tz;m7 -tbna;cny on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon9m*5 1niahag w is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Ear1 ah5 agw9i*nmth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B0 4mza+okss1,8sv4 twcyklmlir.3lu*y/p. o has twice the radius of planet A. If planet A has mass m, whatu01y4,irll+.vsaym3o stwcsl8mp4/ k* .okz is the mass of planet B?

  Two planets have the same surface gravity, but planet B has tl(3 7nb20qvq9o fg rffwice the mass of planet A. If planet A has radius r, 0fovf7 n9q3g rf2 (lbqwhat is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a )mc1 ;b ve*vs0v ,0uqq5iirz2dswvs6spherical planet (mass M). Which expression gives this sate6,00 v mdzvqrv1i;css2ub v )sq e5*willite's orbital velocity?

  Satellite A has twice the mass of satellar31qx8 ,c uuvy3k.h( fre tf;ite B, and rotates in the same orbit. Compare the two satellite's,;f3freu8th kc r1qu(vx .ay3 speeds.

  A person is standing b9qjhnd,k :6m.c /du h(m2z*pb lvh:d on a scale in an elevator accelerating downward. Compare the reading on the scale to the perz pd .d::9h2hl nub(,cjq vdm/*kbh6mson's true weight.

  Who was the first person to realize t .izr( 3hs*zolf:yp /gj.v/j mhat the planets move in elliptical paths aroun iph/s:(*z/j.lfm .r gozvyj3d the Sun?

  The speed of Halley's Comeny2 fdxpm4+y 5t, while traveling in its elliptical orbit around the Sun,x ny5+ 4ypdf2m

  Let the average orbital radius of a pla mbctajor0dol4)5n)h( -mm t 1net be R. Let the orbital period be T. 4 jaltr 51mmc( o-b 0hmo)d)tnWhat quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbitf3j) wr cc46:elm i9ku around a star in the galaxy Andromeda, with the same orbital diameter as the e f ljc9 i)u:6c4m3rkwEarth 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 8m /abc5appb6)zwl)/yw:a kq 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 distance from thk/)zlp8:ap/6ama)5 y bbcq ww e Sun?

State Kepler's laws.st*n1 sdai+dm.dz .bbw8j5 z*q6y *nb

  List the four fundamental fivjvyvm;wia 68 y k2/,orces in nature.

  An object moves with a constant speed of 3 laihrs5 6v+,a0 m/s on a circular track of radius 150 m. What is the acar+s ,h 6ali5vceleration of the object?

  The maximum speed around a level curve is 30.0 km kf9:+bnx yklm6 fclt wmdw.;.gf;e**/h. What is the maximum speed around a curve with twickltwd.*;m 6enf mk .f w9l+:bc gx*f;ye the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a km/eeo4.4k .8jfu nc jpoint on the perimeter of a bicycle wheel of diameter 70 cm when the bike is movim ne./4. fkcoej8u4jk ng 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the ao4pdp9/ iw+rg(s8 ubi xis. What is t +d/oiw(u9 bp4ps rg8ihe centripetal acceleration?

  How many revolutions per minute must a1)1 nowu.yxrdy0 cs1e circular, rotating space station of radius 1000 m rotate to produce an arr0dex1y1u)nc 1ow y.stificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. 5n,v ;d. jl brbrzs//fi2rs6gIt goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorc,fvdg;2b5r 6z/lsisj nr./rbycle?

  A 0.50-kg mass is attachtrq 71ah( n/hved to the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can /at(h vq1h7rnwithstand is 350 N. What is the maximum speed of the mass if the string is not to break?

  A stone, of mass m, is attache9mar-72)r muta/.qbg 4n7bx movtw8 hab ul09d 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 time7tob)aa2mr9rw9hlg um-8xmabb0 q.7/v 4utn s the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in avd g0s x.ky5fngp 93iw3: a2ca vertical circle of radius r. At the exact bottom of the path the tension in the string is ayc09:3 .snfkw5x adgv3ipg2 3 times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s expe c9a1gzy 4 xc2nid,8rf.u. wyvriences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in w 8xgrz c,d2wv yi u9yfn.ac.41hich the plane is flying?

  A pilot makes an outside vertical loop (in which thehpm99t 20x pycb9 cfkd(t1b a* center of the loop is beneath him) o *ttc2mf ya9b bxh90k(9cp1dp f radius 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 hzll5lejn0 3y.r in 96cis weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out oc en3y.ij6nl lz r509lf a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rohx2p379ig j5j.teslk unds 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 coefficient of friction between the car's tires and x7.2k e l9s3jtg5hijp each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. The ihv 6g:ma3 oul( n3hq,mxnv 1)centripetal force provided by fricm g 1(v3u)olnxam6hq v :n,ih3tion is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radiuakncc.7bud7 6 0(s v2zajfr: rs 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and t: fc 6r.( rbkv7s ja20dnc7uzahe road for the car to make the turn?

  A car is moving with a constant speueq trz )5ks+7+w. mdred v around a level curve. The coefficient of friction between the tires and the road is 0k zru7r.) +s mqd5w+et.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 Ol l.1ez7gl7siv4g 9nmk ympic bobsled to negotiate a 100-m radius turn at 35 m/s withm1e 7v sl9gligk47zn.out skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked atiib mv pdtppk/3 c0j1,*ws 1*a 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, ch;ks.jmmff4 2qgpopi;, 2u * banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked h 0/mu7k( maflat $45^{\circ}$. 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 strinueoizdl/eq(4, wg lh 2osi1,6g is revolving uniformly in a horizontal circle ofogildeli(/s 2wqh4,6eu,z1 o radius 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 uniform ra i cq22+mqx-0iq.l p z1pzurk1te to a speed of 45 m/s in 15 s, moving on a circular tracrl0q+2uip pkq-2z x 1mc 1zq.ik 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 protof/ 0m3hkqqw+ kn 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 stanppa38nb 8:kfk.mda q+ ding on the Earth, due to the Moon? The mass.3pk8qf dkbpn +8:ma a 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 attract bh,ixd t d+.ios4*0jqg*fnnp2r/g :xive force between two masses is F. If the masses are moved to half of their initial distance, wha g/*i+t,pio42: njhdsxrbf. xq*n0g d t is the gravitational attractive force?

  For a spacecraft going from a7fw.q:,pwe7fp x -td the Earth toward the Sun, at what distance from the Earth wil pfdqpefx,7 :aw-w7.tl the gravitational 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 ic)rbg8 us9+vl.z ln u6s $7.4 \times 10^{22} \; kg$ 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 "5ye e6ci s+z9bspace-walk" at a distance above the Earth equal to the radius of the Earth. What is her acceleration due to gravit b+ec i65zes9yy?

  The radius of the Earth is R. At whau)df :o. mmgnp(n)v, af)h6emt distance above the Earth's surface will the acceler 6gpue)vm,.oanf mmd: (f))hnation of gravity be $4.9 \; m/s^2$?

  A satellite encircles Marssfhj /,,g m.wk at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity ,k. mwfjh,g/son the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of gravitip76 ik d8 4mqohed66gy is pgim67q io8dk6 e4h6d$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on t oa; o5h88ouiqhe surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r abo8hq o5ai 8;uoove the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg pha2a6)1x i2 svlo/ zvferson change when he goes from sea level to an altitude of 5000 m? (The mean radisl )2z2vav/ 16afo ixhus of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kgphqd5lysc:et)d 0i 97 is at a point 3r above the Eart hes: 70 yqp9ltd)i5cdh's surface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twi/9q4s-jylu kjll5kx ;ya 7 lp.ce its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surf-/.5lx jlaj7qkpk u 9y 4ly;lsace of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun allc8pdz;s/, rr 6vzkf.o lie on the same line, with the Earth between the Moon and the Sun.rsor , kfz/d8v.cz6 p; 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 ballbd4 spw)6ang:v) xfz. /)rpnq is 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 circular orbit about the Earth (in .tu -fan;4eykg+b y* :rrxlb7n6lv3.e., it just skims the surface of the Earth). What is the speed of the satellitybnae ;u:4rrb xn3k7-g+ylt l.f*n6ve? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it si(t;ub. zd hvm6w;*4ve . rg lx5cyr-just skims the surface of the Earth). How long dog.rsvl;y *t4w; zxiu h .dr5c bme-(6ves 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 the surface of the Earth. It ))d7 ( q ucxp; 8cc8*h* cannf4ufqngkis observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the E*) hc7upxdf4aq *c( 8cfk8ncn )gqn u;arth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupim.jsl8c7y- yl:yp tyy,h9u :kter, 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 orb -dxgv,kz ::vbits 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 ( znvx(/:h)ugyx ve n:has orbital radius r, and moon B has orbital radius 4r. Moon nyhnv/ (u ve)x( gz:x:A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter isd8-qj0bhz2wyt p, ng( $7.78 \times 10^{11} \; m$ 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 orh./g2eg 8nqqq5()d 9 bcos* riqty:qzbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth to the S/5:qqbyg.n9)i g *tq dh2or eqz(sc8qun is $1.5 \times 10^{11} \; m$.)