Is it possible for an object mpfzcen lmd(tk))kr 4,dcb ( 3-oving with a constant speed to accelerate? Explain.m(nk,4 blpz)tk3fd- )ecc (rd

  Consider a particle moving with constant speed such that its acceleration e-smiqmj// kd+ n.6ou/sl ar* of constant magnitude is always perpendicular to its velocity..s6/o slerujm i-/ nmdqk a*/+

  An object moves in a circular path at a constant so 8cw7a l:tlukq/+)b upeed. Compare the direction of the object's veloci+qu 8 /ulw:kb7atco )lty and acceleration vectors.

  When an object experiences uniform circular motion, the direction of thesogirlq)j g/ /,;b42q hvy(pj accelerationgri s(yhgq/pj/blj 4 ; )o,q2v is

  Consider a particle moving with constanmk8pm3i - kf.jt speed such that its acceleration of constant m8f3 pm.-kmijk agnitude is always perpendicular to its velocity.

  What type of acceleration does an object movi1jz9ha*t s,rcng with constant speed in a circular 1c *9rjh ,asztpath experience?

  What force is needed to make an object move in a circl-gir1c1uvqk dv sgw0sj1:c ;/ e?

  When an object experiences uniform circular motionjbt v02):coaj zgv(k) , the direction of the net force isojg) k): vt0zcba2jv(

  A roller coaster car is on a track th, vhr wt7xy;o2at forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value for its ce ,wr7;vyxo2ht ntripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (rad2v+0 xmp w+j-l :qnlgrius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of the loop, w r mlpgx+2j+0q-vln :what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then mxl 9 *;e;zojss-b+yvfollows a semi-circular arc until it is going straight up. Just as the plane is at jbvl;y zsexm9+o-s;* 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/g0 wvjeih2q,9htg* z 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 goa3dbp w j 0 )rgmrbk(hhc0tf:* 20ebl9c5uf;fes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around 9(t0p53h c0 rgwd bmkrf:*hfa j u;b0lbc)fe2the curve for the second time, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. The m80+ts5:w cr1qmwhvkn it goes around a curve of radiu1s+m:t hvqw0m wk c5r8s 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 of rad3-ig o en1)abengz b o.23qj*xius r with speed v. If the road is frictionles2gq iegn *bx. -3)3bjno 1ezoas 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 to

  Two horizontal curves on a bobsled run6pzb (*glo1 7h7hf xam 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 radiu1 afbo*phzmlhg ( 776xs curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant (cj7(;ysjyxh8 )cvqryx (fet i)w*t7, but increases upward from the horizontal. Coming around a turnt7v yex(s(c*c); f7j)itxjyq ry8(hw, 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 pa zn3qo)s;rvtmg3o,5o b 2 +errth to have both centripetal zg, +2o)r3vm35esr bontr;oq and tangential acceleration?

  The gravitational force between two objects is pru6nn( -qbr g,joportional to

  The gravitational force between two objects iso0 gwp vr vo:qh*y b:o8izeg-, y//rg5 inversely proportional to

  Two objects attract l)7gux to4,v(0nvb pieach other gravitationally. If the distance between their centers is cut t0, 7)vx4( oblginpvuin half, the gravitational force

  Two objects, with masn0ohvj *k10.1 kvv dgyses $m_{1}$ 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 massun)me(-kx97nl lymv + es $m_{1}$ 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 univeg*k6 tfwl:1 5;vkw) (x kgfogersal gravitation.

  Compared to its mass on the E g50zl5uxhq r5e:74/wzq d-1g l llucgarth, the mass of an object on the Moon is

  The acceleration of gravity on +c*w3y*p muey the Moon is one-sixth what it is on Earth. An object pmyuywc3e* +*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 sy*x 3ufa ,,grrocket's weight

  A spaceship is traveling to the Moo/olb-qvdt7 p/u du,j2 n. At what point is it beyond the pull of Earth's /t-j /p,2uo7v l dqdubgravity?

  Suppose a satellite ws.l1*66 x v a+h c*frpufkq 6ld:mub;fere orbiting the Earth just above the surface. What is its centripetal accelera mc:+6fuh;q alx16s r*kvl.f*6dbfup tion?

  A hypothetical planet has a mass of half thsdpapz 7 hgwk2c* ;b35w jn:2uat 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 w:* gb5w 2p3up7shdakzn;2cjacceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth whar tmv,vk gy8;e/q5)p ww3yj0a t it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earttje v /yv8mk 0awyq,wg5)p; r3h's?

  Two planets have the same surface gravity, but planet B has twice the radiuw98n oy z(za7ms of planet A. If planet A has mass m, a onw8(9zzy7 mwhat is the mass of planet B?

  Two planets have the same surface gravity, but planet B hasszai;on e/y7w((flk ; twice the mass of planet A. ;((yinks7 fl ea;/ wzoIf planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular tc15 bwlrl ,h+orbit (radius r) about a spherical planet (l +5 ,cw1btrhlmass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellitw i3djh gg jt9: h:-axz5d;t,je B, and rotates in the same orbit. Compare the twxwjh3;a:j:- 5 hz g,i ddttjg9o satellite's speeds.

  A person is standing on a scale in an elevator acceleratin 2reoq eigu u/) 5t:tx 3a5ohe,1d9getg downward. Compare the reading on the scale tot5ou35 /)e u9g irto2qd, texeahe g1: the person's true weight.

  Who was the first person to reals imj)w0a/dfhhf g16nv*0 (atize that the planets move in elliptical paths around the Su h)160fianmt ha0/vgsfwj d*(n?

  The speed of Halley's Comet, whi fkidim: 0duxr9- ,fs- *zaae3le traveling in its elliptical orbit around the Sun,-iu*9x a,i-ddz ae:m3ff0 ksr

  Let the average orbital radius of a plane867 pmw8,dc:t /qdmg(x jhvswt be R. Let the orbital period be T. What quantity is constant fo c (/v8,t :dxwhp7gmqjsmd68w r all planets orbiting the Sun?

  A planet is discovered to orbit art. 5p;r z+bqnfound 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 q5fn rz;tp. b+that new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Suzv) ,d n*tmsn0n is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's *s0v,n mdz )ntaverage distance from the Sun?

State Kepler's laws.zqtir;at + l-*

  List the four fundamental forces in7*ns b yq(ky2e,gy ec 1e.kmh) nature.

  An object moves with a constant speedflq;p 2 *y ,blgqb)2 tq0v9vb ;avkzm9 of 30 m/s on a circular track of radius 150 m. What is *vf a);b,q2gqlzy t;0p2vv9ml9bq bk the acceleration of the object?

  The maximum speed around v;gsm n:59 wxga level curve is 30.0 km/h. What is the maximum speed around a curve withmvx:; wsn gg59 twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration o;6d3z4msu)-x6 c;v xlza c kfgf a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike 6x6c;l;xu3azc) ks-4mz gdvf is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locate6cm9d cubnwak36:;cl d 0.200 m from the axis. What is the centriluc;m9kcwc:b3a 6 dn6 petal acceleration?

  How many revolutions per minute must a iiv0+j.ee/aj circular, rotating space station of radius 1000 m rotate to produce an artificiei+i a/jv0j. eal gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn ax6uoa yn 7zy40t 96.5 km/h. What is the centripetal force on the motonu yya4z70x 6orcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The systcflyx;3n5 xk zykpfmg/ r;; 22em is whirled 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 if the string ispz3x2fcnm/ kf;5x gr2lk; yy; not to break?

  A stone, of mass m, is attached to a strong string and whirled in at4c(1n8u:zk9 oq2e+wfdv q yb vertical circle of radius r. At the exact top of the path the tension in the string 8yfqnv9 cz1d4otkq e2:+ ub(wis 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 vertica /y )qy5ve3rhqp2ku9 nb) a5zour2ke7l circle of radius r. At the exact bottom of the pa) qn7y5kva ehy9b 5okr2)u r3pqze/u2 th 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 4:/aez8aqa( ik vicz y06cj(f 2g when pulling out of the dive. What is the radius of curvature of the 2v(eacj z0yfi8/ac:zq 6ai (k loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the eswzl l1-*j) wloop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat e ls1zw w-)j*lwith only one-half of his normal weight. How fast is he going?

  The maximum force a pilot can stanyv /nb clp-.95*l(k6sf8ehee( qs pq md 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 a spn 9ls/p ysq(6c8heevkfm5 ep .*-l (bqeed of 250 m/s?

  A car traveling 20 m/s rone( tikai5 ,1ounds 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 each road s ien1aiko(,5turface.)

  A car is negotiating a flat curve of radi3b w1ede/dzs ,us 50 m with a speed of 20 m/s. The centripetal force pwe,dz/e1 3sd brovided by 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 speed of 14 m/s. Whtf*.lu li6u:fb2cv gnd8 i73lat must be the minimum coefficifucng u*lf8il:7vl t 2bd i.36ent of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant spliat (pp*;w1 9mru0cgp88.3h j pha daeed v around a level curve. The coefficient of friction 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.aa*hjid;pu8r9 a(p1t pwch l8 m3gp0 ?

  What minimum banking angle is required for an Olympic bobsled to negotiate a .()d*t c mjip042iuz 2myrzog 100-myz.i2d2mmr(coip u )*z g0t4j radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 9j + ;o6ua 5bl(tazknsa $45^{\circ}$ 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 o 0zu--owb nx5jf $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banke (pr2zff3nrj4 nhy j24d 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 uniypdjb dl: hb;:vhk qk2x d:1*qh:h*n6formly in a horizontal circ 2bdq*h1xpdh :dkhl*jqk n:: :h6;yv ble of 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 uniformg2mfk23 xcljp *elk uqe )349d rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 50p 3mdkjq49ke2gfcx)u e *l l230 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 ho s4j)r:. q 2zo4pfbqa proton 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 ebu3 4 c)s4)qsr1daat a 70-kg person standing on the Earth, due to the Moon? T3u ds brqe)4sac4t) a1he mass 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 two - 784qyi qp/)iw npz gqlw-7m6uy odr-masses is F. If the masses are moved to half of their initial distance, what is the gravitational attruqyp4 q--)i i7q/z6r wm gn8-7wpdyloactive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from t0vix w ,m2riq8he Earth will the gravitational w vq20xm8r,iiforces 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 Moonhzp0z4u1j,wq vq 3 gtxmc4,,r 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 "space-walk" at66:x jwx,ewq dpa2 s5 :p9cid)r0ekly a distance above the Earth equal to the radius of the Earth. What is her ac6kdy)ew:jxq c5ppw29 i: d6,0x rl aesceleration due to gravity?

  The radius of the Earth is R q4 9c bc9mu5f6k.anjf. At what distance above the Earth's surface will the acceleratjcfa4kcn f9uq6.5 bm9ion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Marsjz6cu)14-t/svxoplc nkl0g6 at a distance above its surface equal to 3 times the radius op g6 /cl0voj61x kls4-)znctuf Mars. The 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 from some planev8 0fseozho8mc75nosh nz9y b 0r,8f9t's center, the acceleration of gravity i ,0o 8v fse9s05 nh87mcozh89zrnfyo bs $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surfacew,ls)c: qu7 b)up2wzt of the Earth. The Earth has radius r. If the objeclzwu,27 wpbqutc: )) st is raised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does krkpj3 n-a h--8dip9 re tk46rthe weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Earkiken9jr4d- t 3pk-6phar8 -rth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius rq+ exqc u b/(4( o(noyxic/9gt. A satellite of mass 100 kg is at a point 3r above the Earth's surface. Whatxb( yu xte(q/ /o(c n+i9gq4co is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its ra0k 03qd0ampa :jz.87qms mfhu-krb1y diu 0ksp-d3kqzf1.70r ham y8:jq bmum a0s. 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 planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the sha- 6w*s /y emqi8xju.ame line, with the Earth between the Mey w-8ji q6/s*m h.axuoon 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 is trans)4l g-stssk+ dported 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 orbitn4u2bkuv7cm jg6.- f p about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of 24jm g- nckp6ubu.fv7the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just s/)dgp ,c b9hy p2;a fqeqi)bve4nj; 1skims the surface of the Earth). How long does it take to make one revolution around the Earth? 1nfh a4g,;d/;qyiq c e)2pj e)pvsb b9(The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular o+ 3uo;gguyvh-v b t;bni:-k7irbit 230 km above the 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 the Earth is+7o-i3gkuiy:g;b ub vnt; h-v $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter7g -m(upv m5ah)z5fcp 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 pi)wh ( 3as:fyzl,r )wulanet 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 orboevsj6 *yu32 eital radius r, and moon B has orbita*3e y j6sevuo2l radius 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 :eukcz2z./k n $7.78 \times 10^{11} \; m$ 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. What is the av 3 ,b)y:g1xlds2hx jmlerage distancb:3l smdj,g1hx xy2l)e from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)