Is it possible for an object moving with a constant speed tk*jwk aqbl+0+ o accelerate? Explain.a +0j+*qbwlkk

  Consider a particle moving with constant speer qyugd2x67t48-m8v h( qtusjd such that its acceleration of constant magnitude is alwaysxhm6q7 (ygdu8tvjs4 tq-8 ru 2 perpendicular to its velocity.

  An object moves in a circular path at a const/o49g upfqt. :b1;oyw un4 mbmant speed. Compare the direction of the object's velocity and bm u u4noo9pmgt4b;1:q./f ywacceleration vectors.

  When an object experiences un3.n:1 z(jlqxevwg6mrd)q : cw iform circular motion, the direction of the acceleratvnxwj z( 1w.3 6)qr:cgdmq el:ion is

  Consider a particle moving with constant speed such mk5dps39xan 6,qvmo +wqh 26ithat its acceleration of constant magnitude is always pep93d2w6vso m,q 5 a+knx6iqh mrpendicular to its velocity.

  What type of acceleration doesu 6o,aebq5k,k an object moving with constant speed in a circular path exp e,kk5qubo,a6erience?

  What force is needed to make an object mov83nbq ;m r x2vwd83y9gdbz +die in a circle?

  When an object experiences uniform cirr2cqe hl y /+trshpwx8e)044hcular motion, the direction of the net forh +t4sqr e2hp4r) c0 lhew/x8yce is

  A roller coaster car is on a track that formwjpk-v q) fg;1s a circular loop in the vertical plane. If the car is to just maintain contact with track atq;fwgp- 1k )jv 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 ciuq;aoh *39 xtrrcular loop (radius = r) in the vertical plane. If the car is to just h;9tr3ouq* xa 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 semi-circular arc until it iu i/1z )(glkpus goin ulikp1g()uz/g 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 curjea, ;u6h hc 0ue-zp5tve 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 goes aroun*j.+fpoj vepe:;xny6 d 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 firsv*yjnoexj ;+fp.: 6 ept time?

  A car goes around a curve of rad3curf5j-qpq v1y1q u 4ius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is 1- jvq5qcq4 uu3yp 1frthe 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 of radius r with 8*4pk- /jp3gyh lkhy 3xz0qkep5lnb7speed v. If the road is frictionless due to ice, the car can still negotiate the curve if th7 l-n0xkz3yp3p e/kkg84p h5 b*hjqyl e 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 banked at the salxotfd92i.de c 1qj* e4mklwx6s: y.2me 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 isos2 1x6f wx.l*2d4ctmd.j9lqie e:ky the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track yj yh 1po4x58xpl0 s(/x7(k eu-rimoyis 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. Why do theyo p78hsj 1-5(ky0y/x(reyio4 xul m px do this?

  Is it possible for an object moving arounku/89b j ;fpt0st hzfk9f-qa0d a circular path to have both centripesjfkbu0-89 ;q kf /0tpht fa9ztal and tangential acceleration?

  The gravitational force between two objects is propo 1n/x0ot:mhg k+n,w lvbo; nsk mf2:v*rtional to

  The gravitational force between t4z0)6 at mpjilwo objects is inversely proportional to

  Two objects attract each other gravitationally. If the distance between thei hg/d/r:tl+dw r centers is cut in half, the gravit //d rwl:ght+dational force

  Two objects, with masses0dbcum5ezo/dm9 ,sknlkf52e0y5 2 vx $m_{1}$ 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 massesaf7fu/n-ey2-a. qq7 oln t *mk $m_{1}$ 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 gravitation.6g, o;2aa28vwbb eeum

  Compared to its mass on the g,vf0un3 w3 pdv fk-y;Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon ilm -36w b-nnv sh3x3vx- u4 7dqy+q,tkfao7zb s one-sixth what it is on Earth. An objedhmv-nq3z 3xn a,t- vy 47-qbok3+w6 b7usxlfct 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 rocket's wf;( x .br+tjrceight

  A spaceship is traveling to the Moon. At what point is itziybrd rjf+6wt .rv,z,u22 y, beyond the pull of Earth's z f2,6rvrtydz +w2,yi.bjru , gravity?

  Suppose a satellite d2t9wh /f6-k+ wxz0d* jk kikfwere orbiting the Earth just above the surface. What is its centripetal accet0 idjfk*kk6w+9kwfd-z 2x h /leration?

  A hypothetical planet has a mass o9fx yguv egfq f1:mm3,;2c8v df half that of the 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 acceleratid yc; gm:,f8fue1 fqxg329vmv on due to gravity at the Earth?

  The acceleration of gravity on eozvd f n(5;4/ae( 2 d1gvbu1ckmtc7i the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that o;ag(edf1cdkb zc m(2/ 7u 41iv5te nvof 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 radiui;q8 c,ql ;v k,ny,ndfs of planet A. If planet A has mass m, what is the masf l , 8,qq;kv;iyc,nnds of planet B?

  Two planets have the sgqs f lr i2p ho;e4k0z)wd-/.same surface gravity, but planet B has twice the mass of planet A.;hek4 lds-izos/p2r) fw0.gq If planet A has radius r, what is the radius of planet B?

  Consider a small satellite mabec:**hdx/et 4n6nb oj:z1coving in a circular orbit (radius r) about a spherical planet (mass M). Which expression givxb zcj*1:nbd :a 6h*t4e/ coenes this satellite's orbital velocity?

  Satellite A has twice th - qosr6rgw0/se mass of satellite B, and rotates in the same orbit. Compare the two satellite's speedswr q6so0rg/s -.

  A person is standing on a scale in an elevator acceleratijjbyq9 c se,q1*oggmtva)ho /:luc.r ,2w/:hng downward. Compare thee ,touc,hoam )c *j.qbg2:/9ghrq w/ j:1sylv reading on the scale to the person's true weight.

  Who was the first person tcr(gvy(z:,v )mp)9hv eo hp5to realize that the planets move in elliptical paths around the h (pzrh)t(v)e9p:,m gy v5vco Sun?

  The speed of Halley's d goa0ic3ir; :z ue2.bComet, while traveling in its elliptical orbit around the cb rz;0e.gauii:3o2 dSun,

  Let the average orbital radius ofseg xgz-d i584 a planet be R. Let the orbital period be T. What quantity is constant for al gzxd 4i5g-e8sl planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromcuw7 ,p9 6w)zhwrr6tzde 67cxeda, with the same orbital diameter asc 7r,u zw)d6w 6xr6hwzc 9etp7 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 Earth to the Sup v :enxn(te0s .vmo72ahik2,n is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What iee :v2ithnm,n( 20vksa. pox7 s the asteroid's average distance from the Sun?

State Kepler's laws.zu0* kt1*kw lu

  List the four fundamental forc xf+p(+m t o7pclq*3zjes in nature.

  An object moves with a constant speed of 30 m/s onjnt,qt 2 (.sfnll3 uz) a circular track of radius 150 m. What is the acceleration of the obttl j) 3n(n2.,fuzs qlject?

  The maximum speed around a level curvef er:6xj5g0gl is 30.0 km/h. What is the maximum speed r:xlggef0 j56 around a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetmp +w ;*7mzgbnal acceleration of a point on the perimeter of a bicycle wheel b;gmm7z nw +*pof diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel ro, ms)2 )cb0bi 0owor1nxdcqtj;;(es ptating at 5.00 rev/s is located 0.200 m from the axis. What is trs tow;o); jp)d0,cqc2e(bbni msx01 he centripetal acceleration?

  How many revolutions per minute t.-w a;1fkxsj /c8rqimust a circular, rotating space station of radius 1000i;/wk . 1aftr8qsx -cj m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It 9i5 t) ;pyrsj ,vi0wjfgoes around a 13.7 m radius turn at 96.5 km/h. What is jtr)5iypsw ; i, fjv90the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whirledc10uzm wp:.lj0w 7t o2 vyx tj2w5cq/o 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 i0tot5p2j/2u wmx 7y:j.q1c wo0lzvc w f the string is not to break?

  A stone, of mass m, is attachfq: j0zac4c 4ced 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 this:f4cazcc4 j0q point is given by

  A stone, of mass m, is attached to a strong string and whirler8k5a/u2r j xd7uf pa.d in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the / pfux2a u85kjrrd7a.stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g 31b yu)6myj zowhen pulling out of the dive. What is the radius of curvature of tyboz6uy j3) 1mhe loop in which the plane is flying?

  A pilot makes an outside vertical loopz-hmjir jml97ac si+)t8 d 1 zwvx6h(2 (in which the center of the loop is beneath him) of 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 goi(c2xdjav - 8hjmirh6 1l7sz)m t+wiz9ng?

  The maximum force a pilot can stand is zk.l*bj 0 zai;about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical d.izl0k a*zj;bive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius h(z3*y-rdr1n pxmnu. d(4 bsmlorizontal 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 coeu(xp dlnsmz r. 3m4(1-*nr ybdfficient 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 7 jov2l f)stj820 m/s. The centripetal force provided o7sj 8f)2vtjlby 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 3hh 5hn;n )pqxspeed of 14 m/s. What must be the minimum cn5qxhh;) 3 phnoefficient 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 curve. The cqr6v s;r 3eqfr*b+,vooefficient of frictio;bqrv*e 36,fq rvos r+n between 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 required for an Olympic bobsled to n/. vxc d:sijm3mkjg g-:n7eo9 egotiate a 100-m radius turn at 35 m/s without skim:j9/mejs . v7igngc-o x3dk:dding? (Ignore friction.)

  A horizontal curve on a bob 33s4czxx m*wzsled 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 radius 100 m, banked at an angzmo.-*g5n bo o -zvy ;jb)yk)sle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m iyji3qcj93,s de w5xk*s banked 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 unifuid7pz:/u) cuormly in a horizontal circle of radiuu7 id:/czpuu)s 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 theabb(imt-u 6q y5t0w )da )o4mh pit area, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of ram 6y4wo( t5i)m bua btdha)q-0dius 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 proton of masr fxk2;oow0+*mt + 5 uppi7kw upu)5xas $1.67 \times 10^{-27} \; kg$ 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 to 6lgel 7.hus pw3hsl:wb1;jc: :s2 kidthe Moon? The m6ldg:pbs:hw2clju3 : .7e;sl1hk s iw ass 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 attractive force between x17)5b .rg fztc+5r egiyj *aitwo masses is F. If the masses are moved to half of their initial distance, what is the gravitatiox.fc rr iag7j5t5 +z*yb gie)1nal attractive force?

  For a spacecraft going from the Earth toward the m3 i.-qe8ns xxSun, at what distance from the Earth will the gravitational f.3x i- xnqme8sorces 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 isphfmh,cgb168 $7.4 \times 10^{22} \; kg$ 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 "spa 7wrw fy* z*n.u+mv1bcce-walk" at a distance above the Earth equal to the radius *y nr wz7m+vb1u. *wfcof the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the dv ,ui 0n3qwc1b k1y,zEarth's surface will the b cu ,qidw3vk11ny0,z acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at ap;rkoss n*,y 9 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 on the surfy o,;kpnrss *9ace of Mars, is

  At a distance of 14000 km from some8 q p*qzlnh;tf 55lcz zt-a0;g planet's center, the acceleration of gravity i-;tq nlh gqzzt;l5 pz 0f5*c8as $32 \; m/s^2$. 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. ;ii90 9b +d e vds,dg3(zifptxThe Earth has radius r. If the object is raised to a height of 3ds9id3(0vi;+ feg,9xdpbi z tr above the Earth's surface, what is its weight?

  By how many newtons does h)c )zn4)d*.iqdabr( sm)bt zthe weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the.()qi thnbdb4zm))a c* )r zds 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 thui tkt4b0+ pg/e Earth's surf/b+p kgu t4i0tace. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's masuqj/r:iu,dc 0v2b km( ,p)jpjs and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this pj(/bki2d ur j,c up,)0vmjp:qlanet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie ongffhyb ;0z3ov, i0o-t 6mr+ov the same line, with the Earth between the Moon andtrfgoy 6f zmh;ob-3i0,v+v 0 o 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 transported to the Moon. dos 7at z )x-(vx3:hok
(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 orb)yo/goetp;j)(qmw/ftf* s .wit about the Earth (i.e., it just skims the )of/j;qyotpew.w(ms t * /fg )surface of the Earth). 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 low circular orbit about the Earths,e 3ivkip5x*r /bh9 h (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around tp9i,ik hh 3* /xvrebs5he 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 Eam7xv8h7ttp/ k sa4g b9rth. It is observed to have hgva8 x4/m9 ttp7 b7ska 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 Jupiter, has an orbital we1 sqs.hokh5 h-/kg(y0rz .h1gj9v qdiameter 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 orbi o*t)hnlq,c2 hts 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 o0 6ivp m32p-tb0dfj6c p:eriin nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r.bv0:2re pitfcop0 d3 -pj66i m Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 1 fnka ne1ve qex77/-c$7.78 \times 10^{11} \; m$ 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. Whauo:vdr.aes-xcz; or 51rz.46.q;gz b :hyk rvt is the average distance from Jupiter to the Sun? (The disy.;kzxhe q - za;bgv.rd:u.coz r1v4r:o5 rs6 tance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)