Is it possible for an object moving with a co k5b cv-hal,w+nstant speed to accelerate? Explain.w-l ha+cb5,v k

  Consider a particle be o -gx7/4mbomoving with constant speed such that its acceleration of constant mgm/x-7 4eb oobagnitude is always perpendicular to its velocity.

  An object moves in a circular path at a constan *r-lasd*k6rjn7a b 3ch :c1awt speed. Compare the direction of the object's velocity and shr*c-6aa akw djnb3r:l c1*7acceleration vectors.

  When an object experiences uniform circular3.7d*arqknzea + i.o 1 skn(nr motion, the direction of the acceleraties . kno*+3.ki17r zd n(nraaqon is

  Consider a particle moving with constant speed such thf bmt pabv::p62 pe1p3oj0m5 xw+z*rnat its acceleration of constant magnitude is always perpendicpz: ea 12*v npmrt05bp p6b 3f+omwj:xular to its velocity.

  What type of acceleration does an obi.)x6zy g10 +szy fc9;zjspi nject moving with constant speed in a circular ypi+ys x 90fg;)z1 j.z6zsc nipath experience?

  What force is needed to make an object move*fpl1nd 8ae 7lvu4. i;9 r+ bdyr;jldq in a circle?

  When an object experiences uniform circular motion, the direction o bwr)tk*x4w*gmw9uc)b n;:tg d0wl3nf the net forcegktw c)n rglwu9xd*;t:0bmw 3 )n wb4* is

  A roller coaster car is on a track that fc:yk) xqszve/s 80 9.eo+eanh orms a circular loop in the vertical plane. If ths:zya8o9n.0 )k ch/+vq xeesee 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 t7lcl8gol66e on a track that forms 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,6ctlo7ell 8g6 what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then 1hvtu1.;uokx ;b0 eknfollows a semi-circular arc until it is go1ku etk.b;u1x hon0v ;ing 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 curve ofi93n1p aookof3a/vfzuas 5 6/ 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 gmc zo0j;:r* to1o6 u35wam jdfoes 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, cmt6foj ;r5 c0m1zoa3 d*juw: oompared to the first time?

  A car goes around a curve of radius r at a constant speed;oh j/jhn2qr ne82ib4+hec5p v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on b2 eoj5r;q n8 h2/hnpj4+ceih the car as it goes around the second curve, compared to the first?

  A car of mass m goes aro5gpd0d5i z ycd8,q uk.und a banked curve of radius r with speed v. If the road is frictionless due to ice, the carckdyp,zq gdi55du08. 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 banked at theqb/ b7+pyde 9s 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 speq+bpy 9/esd 7bed on the larger radius curve?

  The banking angle in a turn on thekrh6f2d xsu5 ( Olympic bobsled track is not constant, but increases upward fu(s rd26h xfk5rom the horizontal. Coming 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 fgh1 -p4*x+fv* wj ofscircular path to have both centripetal and tan 4g+w*psjvfxhfo1 f-*gential acceleration?

  The gravitational force between two objec017xmlcj. bz1pw vvaq 2dwt5/ ts is proportional to

  The gravitational force between two objects is invenb , t gqxiin-+0)pprbk)k r,l9,6dsoq3 i.xcrsely proportional to

  Two objects attract each other gravitationalgl7eb6 z5j1w/*qwnkne qee-05y x2 fv ly. If the distance between their c2e qekwb*/0eg5 ljw5 nz7xvf -y1 6eqnenters is cut in half, the gravitational force

  Two objects, with mae 8gfe)l/b q.trc48ufq:(pchsses $m_{1}$ 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.tjqjwse*216)u)wnq bnse b , $m_{1}$ 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 gravita;q/iy jzl)jz;tion.

  Compared to its mass on thebeo:+cfof z71mcv 3 kmve bx9/3rp,/x Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An:ex3fyvmoi,s q06.)2 pck1 7g rkfyjw ob s vjm6: x3.,pgfykyeko0 ic2q)1fwr7ject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Eartq98ywygwj co v3k *qzkw933i,h's surface, the rocket's weight

  A spaceship is trave7gb7t u6tn9 yp 1dq-qeling to the Moon. At what point is it beyond the pull of Earth's gravity?9e q16-tgqpny7db7 tu

  Suppose a satellite were orbiting the Earth just abovetc*q 0wm4nmf+ the surface. What is its centn +0wmt 4qf*cmripetal acceleration?

  A hypothetical planet has a mass of half that of th.f.b xz(en2naa e/cn *e 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 acceleratin(a .a2cnfe/*z. x nbeon due to gravity at the Earth?

  The acceleration of g sjks+cg i1+h;ravity 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 Moon's ma+ssigc h1+;k jss compared to the Earth's?

  Two planets have the same sua14z phzp 3.vbrface gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is th zvh4z3pp.1b ae mass of planet B?

  Two planets have the same surface gravity, )k8. v h/lqqw w.hwrb7but planet B has twice the mass of plane7bqkhw. vw w8lhqr)./t A. If planet A has radius r, what is the radius of planet B?

  Consider a small satellic49 4*9tg2dsyx8x jzpatg s*n te moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this tz2g4ypd jnst99s 4gaxc8x**satellite's orbital velocity?

  Satellite A has twice the mass of szs-/,q(o 7zls wuc gi5be ;s9patellite B, and rotates in the same orbit. Compare the two satellite'g zz lip,(s-ses9 bcw/qou5; 7s speeds.

  A person is standing on a scale in an elevator accelerating downw h xcth m;+*dxfh4lao.d:pa0/ard. Compare the reading on the scale to the person's afc4a.;o+d xhl /h hd0t x:*pmtrue weight.

  Who was the first person to realize that the planets move in ellipt (l4+xlpeft6 gical paths around the Sunl4fp+(g 6l xet?

  The speed of Halley's Comet, while traveling in its ellipticalp m-sy oo0h3f2c5)aar orbit around the Sun3)0o h2my apcsf-ra o5,

  Let the average orbital radikr *5x b8/vwjmdnr60bus of a planet be R. Let the orbital period be T. Whatrr5xv /jm608bb nwd* k quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a st p -ayvxi2g0+sar in the galaxy Andromeda, with the same orbital diameter as the Earth ar-svpg a0xy+2i ound 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 Sun is defined as one "s .df)b,mx8ir astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's averagf, dmbi.sr8)xe distance from the Sun?

State Kepler's laws.qk 2qf pfb7c 8(x/ipi/

  List the four fundamental forces qg /9 5tvgtqhdo3eg7 /in nature.

  An object moves with1e(b dzqs,c(9q k+nxz a constant speed of 30 m/s on a circular track of radius 150 m. Wha1xk zbqecsq,z( (d +9nt is the acceleration of the object?

  The maximum speed around a level curve is 30.0a6eqof,ulnj(9 8b 2 vb2nhr:f km/h. What is the maximum speed around a curve with twice the radius? (Assum:q2ur fa9 h (6bfn2,jvb8lnoee all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicycle w3 02nz0ebksz82kkrzf3f u sk 3heel of diameter 70 cmzs02ke ukfn3k203fsz z k3b8r when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m fromfn( g*em7bl2see e9q (3 kn4dm the axis. What is the centripet4gsb e9(e (*e 2efql 7nk3mdmnal acceleration?

  How many revolutions per minute must a circular, rotating space station of (-z. 0e7nw0 6ibkz*dnyqm e9yf*mxdt radius 1000 m rotate to produce an artificial gravity offz mi.e q-mdkeb z*yxy009 nn* 7wt(d6 $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m r wslaq+mnjkm zm + b:640;5-du aw6ebjadius turn at 96.5 km/h. What is the centripetal06e: ;wm5zmskuqa++b ldj6m 4a-jn w b force on the motorcycle?

  A 0.50-kg mass is attached to the end ofe1i80 ecpvntd (+; vnh-krt+ b a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the mae+v;nic r k(p e+b8thvd 0n-t1ximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a vj3r7h yf8/,r7ff uikmt 61oxq7zh;u rertical circle of radius r. At the exact top of the path the tension in the string f 3/,yk1rfzhh xrm6j8 q7 utoi7;fru7is 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 strong string and whirled in a vert 8wons y7qy q gv fr.h81g+,9+cwyodz5ical circle of radius r. At the exact bottom of th vf1.5y +yoo gq8zr, dcwq8syn9+7whge path the tension 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 acceleration of 4g when )f 7f3ffp.o3tkbu+ rvpulling out of the dive. What is the radius of curvature of the loop in which t3k u37tf fp.fr+o bv)fhe plane is flying?

  A pilot makes an outside vertical loop (4s4n2qjw q dh(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 s(q44d2wnhjq ng?

  The maximum force a pilot can stand isnu9 g5c1:4 vl1jy orxi about seven times his weight. What is the minim1 rvoc1 x:ij4n5ug y9lum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s roa,pr :mjhb03m0uns uj lmgms7,, tw*.unds an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car rou7 30njamtsmpuh*bm:lg .,rw u,, m0jsnd 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 w7 d8*os *mc1 glqwp)6ymmkhw6ith a speed of 20 m/s. The centro)w1d m yq6gc*wm kslh7mp86*ipetal 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 3v *rq 944) veeva5zv9a pva(cs(c yzqof radius 50 m at a speed of 14 m/s. What must be the minim)avcqs9 va 3qv (v9e*z(ea4y 4r5cvzp um 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 around a level curve. The co; bsagfb;o,g5efficient of friction between the tires and the road is 0.40. g ;;bg,bsof5aWhat 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 t 0k/fg tjd(wj +*zoq..8h jncpo negotiate a 100jowp fj .+8j0dnt*z/gq .kch (-m radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on v57thdv:sr qytr- 63ygtg p*4a bobsled 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 angle csh,t m iy4at/ c: e0uo+z6.gxzmw/ w4of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked a p,q) z2jjmh;p-p 1sh4io ma)tt $45^{\circ}$. 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 ie/p .3ww 3tpx4d2bo5ndud; e( uf (jgas revolving uniformly in a horizontal circle of radius 0.523j d;f dteww (4.pao 5bg(udxn/u3ep00
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 gkyw 1gqf7*9r, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (ong7k*r 1gyqfw9ly 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 g--xo xc, oau2mass $1.67 \times 10^{-27} \; kg$ 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, k;xk q5x+5mqjf7z ag0due to the Moon? The mass of the xg;xjka 0q+k7qf z55 mMoon is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive forcppy2z,s 9 ye.c v, ejkhggcj4grd*27 8e between two masses is F. If the masses are moved to half of their initial distance, what is the gr9yev4 j.yg,2pr2*jk, hepg7c d zg sc8avitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distancxpuk*e dv. w)( -z1fo(sy /lyqe from the Earth wi*1wo ez/ qulxk.-)yf (yds(vpll 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 is jkz 0akfl4 g) hu8lxd f(g/eo( gmfkrs1 v504/$7.4 \times 10^{22} \; kg$ 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 "spaeuu y/+d2a zapi:6r.ace-walk" at a distance above the Earth equal to the radius of the Earth. What is her yze6d raiu. :p/ u+aa2acceleration due to gravity?

  The radius of the Earth is R0iim9tl q3qh0 . At what distance above the Earth's surface will the acceleration of gravity 90i3im0lqhq t be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its cpm-zs l9qviiywa; 913c wb3; surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity oqwz3v9swbp; l cc;3mi1 9i-ay n the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleratx926oly a v:www7srw tb*7iy. ion of gravity iyo.ywrib7w6*wx9 l 7avs:w 2ts $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the qe.dfw1nu(rl-1e mv -p-.n v jsurface of the Earth. The Earth has radius r. If the object is raisedn.ee p vm--v.ur( -wdln1qj 1f to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weig0 + i-lwjde5zxht of a 100-kg person change when he goes from sea level to an altitude of -xdwjz+ e0li55000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of ma 77qf/ /03 87woyynkea cird.dv hf:rcss 100 kg is at a point 3r above the Earth's sua:vnyew c.k 737fhf7oycqr//d0i r d 8rface. What is the satellite's weight?

  A spherically symmetric planet has four times the p4+j9i r9zakv Earth's mass 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 pkij 9v 4+a9zprlanet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on t6wue9j* b5evct1h w8+xhgvl1 he same line, with the Eae9 b1jtve cx1lhuvh*856w g w+rth between 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 kmyp95tdt 5u. 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 abo :v-e;fef i8uyk5)cp lut the Earth (i.e., it just skims the surface of c:)eu ;ly5e-i v8fpf kthe 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 Earth (i.e.hvhd8u h 3)us8, it just skims the surface of th3 d8uvu8)hhsh e 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 fa+5o7mp*whsw .vgt q hjv;d57u7m8z above the surface of the Earth. It is obsvpv78m;dm7 as+5.q j*thw7woh fu5zgerved 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 Jupit2w a3 jcksw/(ger, 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 orvhajh ut m2h7/zwjt,r*92l :ybits 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. Md c5kq*qz7 v xlv w3ampaas .l5d/x.q6,gzo: -oon A has orbital radius r, and moon B has orbital radiuxo m6c7zlsgxlv3w-.a 5z*,d daq q/vka.q: p 5s 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is pn1yr lbetkb(x::- ,x$7.78 \times 10^{11} \; m$ 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. Whaneddhi l :(l*,t is the average distance from Jupiter to the Sun? (The distance from the Earth to the Sun ilhldi,n (*d e:s $1.5 \times 10^{11} \; m$.)