Is it possible for an object movi /hhhy0x:s 7gay5a:vov1 q4nong with a constant speed to accelerate? Explaino71hn/ :yog0s:ahvhyx 5 v4qa .

  Consider a particle moving with constant speed such that igdk+nzyd5 ,i u/1(ktv ts acceleration of constant magnitude is always peky tv1z, (gu nd5k/id+rpendicular to its velocity.

  An object moves in a circul rqgi+* w0/,iwz nlx*gar path at a constant speed. Compare the direction of the n+ gi 0z*r*w/,wqgixl object's velocity and acceleration vectors.

  When an object experiences uniforh5s xxz k5 rju/ybec. mrv.)8( 4fv/zmm circular motion, the direction of the accelerationm/yv58z4jh vue rmf/k)sb5. z xc(x .r is

  Consider a particle moving with constantm6t7tbs/3sqh( x)n 5alk )low speed such that its acceleration of constant magnitude is always a(s txlm53)/sntqkl 7 hw6 b)operpendicular to its velocity.

  What type of acceleration does an obj lrv3;/s. sxk:i+pxqt ect moving with constant speed in a circular path exp/+vx.ti3 ps:sqkr ;xl erience?

  What force is needed to make an ob3g6oiv 6aq+- wuz5iz0za)6 h0e/w gcijd3kl r ject move in a circle?

  When an object experiences uniform circular motion, the d77ckiiq ys x;f+k,so5a :gu m1irection of the net forc 7ogqk1csimi+75: yufxsa , k;e is

  A roller coaster car is on a track that forms a circular loop in the vepg9hpo4 xc1 ss-u4 h8ertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum c4ug1ehphopss 4 x98- value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) r1 s;smz6h-dk 46fjzz is 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, what is zd s4z16-jkh ;mr fz6sthe minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-r :5mitlj9 bvxav-d52circular arc until it is going straight up. Just as the plane is at its lowest point, the forceir v2tmv5:xd bl9-5j a 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 curu7dw2xal * .kz,jghil*pmy::ve 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 goe0yns jt,epqlj ic+/k62 35 tdss around the same curvp 2s+q6jijtnty0k se/,c l d35e 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 first time?

  A car goes around a curve of radius r at a constant speed v. kg 7;6ujrhwt, Then it goes around a curve of radius 2r at speed 2v. What is theu ,;6hw7gkrj t 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 speed v. If the ro ldtqe9tj0(j25+ n)/zi jhzqtad is frictionless due to ice, the car can still negotiate the curve if the ho zj(9zqt+ltt5e0i d j )/nqjh2rizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run a-vte7 cq9ui6are 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 smallt-q69iv c eu7aer radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a b a: /0 v76sex7wk 8gyc-vidfbturn on the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobv78cb vgfi/y bk6e-s07wd a x:sled 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 b mnoomy4lz j1 g.3bt3-oth centripetal an ng3mo.34 jmt -olzb1yd tangential acceleration?

  The gravitational force between two objects is pd3lnk 48b.z toroportional to

  The gravitational force between tao r.g0 3xkixm3/lsiuc5w-a /wo objects is inversely proportional to

  Two objects attract each other gravitatiz66x/ iaoxj8 *b y7hcdonally. If the distance between their centers is cut in half, the gravitational y a/o66 78d*cbjx hzixforce

  Two objects, with masse*+ phl)j8xdrz-j 5za tr;xnr7 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 masc,: 8 fj16b sq3tlfmqbses $m_{1}$ 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(kedv,1zivk . gravitation.

  Compared to its mass on the Earth,;4b+z kqzbm91fbvd yhbd6z 7/ the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it + qbg,bk pa*w j774mnmis on Earth. An objec4n7+ jmq7kmpwb,ab g *t 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 weiv9qpsameaj4,0 iyu 3+ght

  A spaceship is traveling to the Moon. At w 85xmvlcn42 duhat point is it beyond the pull of Earth's grac54 8vlxnm2d uvity?

  Suppose a satellite were orbiting the Earth justcz4l 4hm y7xqn0e:uj8 above the surface. What is its centripetal acceleration?e7x8m:4z4u nhj0clyq

  A hypothetical planet has a mass of halct+8ein+8sj da1 q+w uf that of the Earth and a radius of twice that of the e n1d qi+s+8ut+8jcwa Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on th(ss.d pbwo/:1i(f awuqqxw n i28)2eqe Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that o2s wx( qw:e)wa2(u.pfs ibnq 8/o 1qidf the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity9p6asuz;96immz c4m l 7 4qfgj, but planet B has twice the radius of planet A. If planet A has mass m, what is the massjl4mp7;auczmm9f g z4s9q 66 i of planet B?

  Two planets have the same surface gravity, but planet aeb6* */(ipiz0mvac:qd+svt/zs uz :B has twice the mass of planet A. If planet A has radius r, wzzav b/m a*:/ u(csed6:*v+i0s izqpt hat is the radius of planet B?

  Consider a small satellite moving in a circular orbit (rdo*:ke)p d5 xtadius r) about a spherical planet (mass M). Which exprdkxp5o e)dt*:ession gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit.hsm4g78 )fi vp Comp )f vp48g7mihsare the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compare tp9 8yqy:p l6 kcg+e. fdg9zh0zhe reading on the scaczghgy0pepd6 l+ .:fk89 y 9zqle to the person's true weight.

  Who was the first person to realize that the planets move in (ec++k y- b3rf wberl:mri7u2elliptical paths around t cek3(y m+ru b-wbrrife +l27:he Sun?

  The speed of Halley's Comet, while traveling in its ev rb, 5f-j./b2 t xujx2g/im8ms*j ckslliptical orbit around the Suvb2- rx/*/itk 8m2ujs ,mj xb5csfg.jn,

  Let the average orbital radius of a planet be R. Let the orbital period bez+pp 89ohx/wafsb d;. T. What quantity is constant for all planets orbitih /8po9zfpa .b+ wd;sxng the Sun?

  A planet is discovered to orbit arounn1pok c1 e5xn*d a star in the galaxy Andromeda, with the same orbital diameter as thek nnxp1o *5c1e 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 Eart+pjmyxsv9g8(o4d gty g7i)6th 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 avergp6od(m+y9sg4 ji) 8gy7 xvttage distance from the Sun?

State Kepler's laws.zy hq2 9y,+dx4xx.voh

  List the four fundamental forces in nat/3qp9du5wf phm 5o yzax.4s a*ure.

  An object moves with a constant speed of 30 m/s on a circular track of ramu957kd+ajyj9,p8dzc u)d zwdius 150 m. dpjwuj, kd za9z)m98cu5d 7y+ What is the acceleration of the object?

  The maximum speed around a level curve is 30.vrb d3fjw,.gs)* ecj0,pub4h 0 km/h. What is the maximum speed arou,bhdb wpc3esjf4r *gju.),v 0 nd a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perim,w:sln ap)imw :f0ct 1eter of a bicycle wheel of diameter 70 cm when the bike is moi m wwt:,n0c:pf s)la1ving 8.0 m/s?

  A point on a wheel r. /pu6 xr)tot hh1;ou;b 5qsph4,6izy1gsim wotating at 5.00 rev/s is located 0.200 m from the axis. What is the centripetal acceleri;1/m.1p),6wgyiq hr suth 6xho z5tbusp 4; oation?

  How many revolutions peo/ b f;)7kk jr20vqrhfr minute must a circular, rotating space station of radius 1000 m rotate to produce an r7 kq0frv/2hbokj; )fartificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius ta)t h/bw j)ijwb)*3p -9nyxqgkv:: czurn at 96.5 tbhywn93jw )* avbg kqzpx:j :/ i)-c)km/h. 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 syst z7q z+qyhnvbqc3-(x1 em 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 s+zqq-73zcb1 h(x yvnq tring is not to break?

  A stone, of mass m, is attached to a strong string ap 2(hq-xl9 reknd whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times 2p e-x(9hr kqlthe 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 79x+e,gicr8pc 2tq d8fik 6oein a vertical circle of radius r. At the exact bott2dgp6+c7q8co 8erixkte9,f i om 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 jet plane flying 600 m/s experiences an acf 7bro8j9164wh uubmrceleration of 4g when pulling out of tj1 u6rrho74m fw u9bb8he dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outsi14naq4jz7c nx de vertical loop (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 going1nqx7j44caz n?

  The maximum force a pilot can stand is about seven times his weight. Wnse(y9qot byj(+ yvrj +( u)9shat is the minimum radius of curvature that a((esbuvst9j r+q yyj+( on)y9 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 rounds ux0xjj 4pll+ugsp g-s79*nd*an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve oflug4g9xssp*p jd * xnj-0ul7+ 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: pi9pwaz,9 yh m/s. The centripetal force provided by f99ph: w,iypaz riction 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/c2l z(.me 5 c9pmbtnu a speed of 14 m/s. What must be the minimum coefficient of friction enztcl9 2u5mbp. m(/cbetween 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. T41+;oxlno wqj7 is4i m 5z8py2jcr- lzhe coefficient of friction between the tires and the road is 0.40. What is the minjsmp5j7zw ;q l-1iy44i lx oz8ornc+2 imum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled t0 djm2.5i sdgqv hsqzrz:c1)( , +mozro negotiate a 100-m radius turn at 35 m/s without sk1si(: vz+0 qhoqrzz .rdm2m5)gc, s jdidding? (Ignore friction.)

  A horizontal curve on a bobsled run is ban q:j,8k) urwcuked 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 az- 7c h21kxhkpn angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank d(.(do.jjj;cjk (7mbteaz97d ik2uzed 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.so(h5k( rvpq a string is revolving uniformly in a horizontal circle (oq(5skhvpr .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 88fg sj0dh.kh the 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 radius 500 m. (only fill in numerical val8 0gkjsh.f8dhue 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 consiy:nn2lr9px kd 25qb1+zc3 opl sts of a 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 a 70-kg person gic9c-dpgw8d(w 0 rqmpsn+ 7/iwfp*) standing on the Earth, due to the Moon? The mawrwc9 ng d s* gimp-pw7/c)+q(0fpi 8dss 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 b,8m u5gp qezvt ccy62wx lm g9.09m4gdetween two masses is F. If the masses are moved to half of their initial distancdcu2vp4l,w9 8yztq g.g5 06cxm9 mg mee, what is the gravitational attractive force?

  For a spacecraft going from th6 spz/ u nu 3mxkm:rd7o86xirn5dj 2x3e Earth toward the Sun, at what distance from the Eartho33p7j /:2minunsddm urr58x6kx6 z x will 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 Moonkgj ww/bxwb3tyg4 ;n 6a, fd4- 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" at a distance above*reeqp 4xw8,k/ hg3dvi+ nzk82ytx9 m the Earth equal to the radius of the Earth. What is kvkw, +q pe9* z4 hemn3/xiy8rg82dxther acceleration due to gravity?

  The radius of the Earth is R. At what y.x.spu 5bsmi ec 38f;distance above the Earth's surface will the acce eu ps.8 3xism.5byc;fleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Madbja7 2 nz -jvun7r6m)rs at a distance above its surface equal to 3 times the radius of Mars. The acceleration of n7ubmj r62-z ad7n)vj gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from -3 kh1)i fgn(uvokt j+j82qcgsome planet's center, the acceleration of gravity is)(t -oq2v8 k +gihfknc1j3jgu $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N nz3b-r9)fj v zon the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's-jzbf)r 93z vn surface, what is its weight?

  By how many newtons does the weight o 4eqwkwu9tj 4+f a 100-kg person change when he goes from sea lw t+44ju9 qwkeevel to an altitude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellitead* kh -jn50b8pqz:,bxr :xkh of mass 100 kg is at a point 3r above the Earth's surface. What is the xhbq*zn xb::hkj ,5 prdka- 80satellite's weight?

  A spherically symmetric planet has four times the Earth's; k khv,ly(rzflib3.odt 4+; l mass and twice its radius. If a jar of ro,lldz.4 +fk (3lt ih ;bk;yvpeanut 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 a3s(l pqvu v4u0uzm dl5 *up7 aa9cy)5gll lie on the same line, with the Earth bez( 5v mav*0su7c5ud)auu4p9qy3pll gtween 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 is transpo 4e3rmvpp4sq3p)veo; t2x t+orted 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 c2bm6gt 9sd(kx. uppn 0ircular orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speexg.0296u bptkmd(n sp d 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 Earthdhb3t q+q,t;t (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Ea ;ttt,b+hqd3qrth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circularg9q*/ nxz5l+km+ ;wcg-stkel orbit 230 km above the surface of the Earth. It is observed to hc g -lste+9*;qxm5/zk k+nwgl ave 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 Jupitersg+q wd8vt4h9kp4gv93gf g 3w, 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 planet with a radius opts+axy5w- b3f $422 \times 10^{3} \; km$ 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 ox2 22lp ev/7gzfz j4rkrbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it takr2 7p4fgvj z2 k2xlze/e moon B to complete an orbit?

  The planet Jupiter ipdbr/,-d8h 4uvtc( bvs $7.78 \times 10^{11} \; m$ 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. W6 xmspg *5aksk(mp.8aka+;ak hat is the average distance from Jupiter to the Sun? (The distancepmas;x.8 (k5a m6+sa*k akgpk from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)