Is it possible for an object moving wi :th;8fr;k1w po uq*lcth a constant speed to accelerate? Explainq*k 1l8t p;ch orw:f;u.

  Consider a particle moving with constant speed such that its acceleration of connp62amr jaj5a.8cw0d stant ma05cr 2jnwpda8m6 .ajagnitude is always perpendicular to its velocity.

  An object moves in a circular u2 nqan6-p7mz,iow;k path at a constant speed. Compare the direction of the object's2;q - zon,k7i6unpw am velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of fmkj) etxe)o* 4h8 9xythe acceleration isyxtfox*m8ek h)e4 9j)

  Consider a particle moving ws/gnm t+*cy q*qas;v1ith constant speed such that its acceleration of const/ vtyc*m1q;gsqas *n+ant magnitude is always perpendicular to its velocity.

  What type of acceleration does an object +y //b r1kw2 yqgxv*rl1- qomymoving with constant speed in a circular path experienc /o y/bmq1 rryg21k+-*xvlywq e?

  What force is needed to make an objes h) n16 u*f;jlfqtr2grs l9ov6up8. pct move in a circle?

  When an object experiences uniform circular motion, the direction o5y1 s x f5goarin 9ca+g44r/shf the net for5 y /1nr o4sgrxs9a 5agi4chf+ce is

  A roller coaster car is onh 7: llcmltd,c+c/2h x a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top: h, c/c 2+cdht7xllml of the loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is odchg x64j68o,f3.aeq0 bdjno n a track that forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain con 3cqh06 go,o j adn.d6jex8bf4tact 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-ciruoivml*3 -w6jcular arc until it is going straight up. Just as the lijv3o6 wmu*-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 c9p6c b w05gu,,njde5w j*qwgfurve 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 ummh4 w mr)p8,r at a constant speed v. Then it goes 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 secondph,8mw )r4 mum time, compared to the first time?

  A car goes around a curve of radius r at a c*f h.2wc ovzu0onstant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripeta2o*f u.v wc0hzl force on the car as it goes around the second curve, compared to the first?

  A car of mass m goes arou6d6 b y*tbzz7uc6jh4cnd a banked curve of radius r with speed v. If the road is h6bcb7zj4yc6 dt6u z *frictionless 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 run au5; nv nu8; qmyf7ji7xre 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 radius v mu x7j8uy7nfi;;qn5curve 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 consp19e3bbyni m.ejwj ewmj81 )( tant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb ybmwmwpj 8.)3je ij be(n11e9 the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object xmwr dycn;bj5( fj,4:moving around a circular path to have both centripetal and tangential accelerfwm:j 5n x,4(jbdycr;ation?

  The gravitational force between two objec a m-k:bi7+qfyts is proportional to

  The gravitational fon zg1q +t52ji6m)pezhrce between two objects is inversely proportional to

  Two objects attract each other gravitationally. If the distance between sz cub2)5et m/oq3k -mtheir centers is cut in half, the5qu/ 2kzo)mm -c3e bts gravitational force

  Two objects, with massr+yd vch97) yzbq; dn9es $m_{1}$ 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 ju:wh4m e)f7r$m_{1}$ 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 gravitlj45q7l40t p mt kfob+*mqd jjxk4e 7,ation.

  Compared to its mass on the Earth, the mass o3qb6c9c *w c mn2yea8v12rz j w+g:povf an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is one e3:)ho2xl qz Earth. An obhle2) o:q ezx3ject of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away fromuzv48e1zii yzov8ahz k / -xk43 -a,iy the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is i9)jp z(ia6uxo t beyond the pull of Earth's gravity? ij(xz6)ao9u p

  Suppose a satellite were orbiting we9u, db7e e;cctc7m.+tu jd/the Earth just above the surface. What is its centripetal acce.e/cmd;cbt ewet7j ,d 9u+c7uleration?

  A hypothetical planet has a mass of half that of the Earth and a radiu)hy .nxu o,s31 orgcw1/flqv5tp;k(xs of twice that of the Earth. What is the acceleration due to fkxo.y;vt 1rn,gwolpquc ()/hx135sgravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Eartvt po3 09dkm4lh. The radius of the Moon is one-fourth that of the Earth.4t3dvo pk9m0l What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet Blg mv wi/gfy:(6u/4 mohg g+0d has twice the radius of planet A. If plane0/ ogh+:v6fmiggd4( m /uwlgyt A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twicl-gsn8j5c(p +ztk- ate the mass of planet A. If planet A has radius r, what is the g+ cj( 5a kst--tzpnl8radius of planet B?

  Consider a small satellite moving in a circular orbi4b 1c spvry+9:sa:; ih0bmmkxt (radius r) about a spherical planet (mass M). Which expression gives this satellite's+p br :s:cs v9hi0x 4mbkyma;1 orbital velocity?

  Satellite A has twice the mass ooe2 g1aunt2d b8bfx )8f satellite B, and rotates in the same orbit. Compare the two satellite's speedto b2uexbd82n fg1)8as.

  A person is standing on a scale in an elevator accel7.unjx 7 i88u-7rh6pra xccaherating downward. Compare t7xhxij 8h8u.cr ca76apr u7n- he reading on the scale to the person's true weight.

  Who was the first person to realij1rd3it9: mn3dj kh3hze that the planets move in elliptical paths around the Sund:mhdi1 39k 3ntj3 jrh?

  The speed of Halley's Comet, while traveling in 1piq9w4*ipz br-+pvz-mx8z8zl+g :t dffp5p its elliptical orbit around the Sunipprfv+8zxp +lb9i- zwg-p8 z p14tfqd *:zm5,

  Let the average orbital radius of a pladu2vl wb mvr ej//4.w3net be R. Let the orbital period be T. What quantity is 2wjw 3 4l/urmvd/b.v econstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in t-l v *uj-)vv,bo- /qjhf mpg8ohe 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 that oqvhp/- j8u lmvvb)*f,g j-o-new planet be, compared to the Earth's orbital period?

  The average distancefjaanv :rd q7i35y: *n from the Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one:j vnr5q:n* ya3fi7a d-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.(, mmm:bg rh-r

  List the four fundamental fo n.b/yhg2oj4ohd.d ;.)spbat rces in nature.

  An object moves with acjm- +x q-)xoa constant speed of 30 m/s on a circular track of radius 150 m.-xq-xj)m+ a co What is the acceleration of the object?

  The maximum speed around a level curve se) g,r9 iph5;uwbox( is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors rep,( we59xigrshbo;) umain unchanged.)

  What is the centripetal acceleration e,+ j8 jfy +g4dyy4gbjr00emz-qdal. of a point on the perimeter of a bicycle wheel of diameter 70 cm demy.-gqe 0+d f0z4rl+j ,jbjgy y8 a4when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0ojei8n 2ex d 6om*+aa(.200 m from the axis. What is the centripo6 +nai 2eme jo(8xad*etal acceleration?

  How many revolutions per minute must a circular, rotating space station of r;, 3pg ;9a8y)v ze(f1k kflhtg nuq7koadius 1000 m rotae f k1fht;aq(klok8g yp, z7;u93gvn)te to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 rgoju+0 e r1iux8wwu:r mv,p (+io13yc)u zp)m radius turn at 96.5 km/h. What is the centripetal force on + r om1xuz83 j uu)(ry0we+uvirc o)iw:1,gpp the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whirley 7thju2 jsvce1ej(:0d in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is th0uj7: t(jh1 2yevjesce maximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirledk6-ek 9- ud7f.izm1bo; tu kky 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 thk.k9e -u17zo-k kf ut;biymd6is point is given by

  A stone, of mass m, is ktc+xb-a +fh5 attached to a strong string and whirled in a vertical circle of radius r. At the ex-cfb+ 5+ hatxkact bottom 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 acceleration of 4gpsk.+k ,3c q62oezd cx when pulling out of t,dskc.zpo2kq6e + cx3he dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which t-5 suo; tm1vyq k2v2*/ljvk tyhe center of the loop is beneath him) of rad-vuv5stv1m* 2 ol j2kyqy /t;kius 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 abcv+n+mf-d,wexn 8mz 1out 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 a+ m,1-n+v 8nzcmwdxfet a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with tx 7ur1m56)vvuf+qcy ghe tires on the verge of slipping. How fast can this car )567v cqxf +u1gv urymround 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(od 9g6+bsjz(j.xj5kqo 5ocydy+ - cy flat curve of radius 50 m with a speed of 20 m/s. The centripetal force provid+( cq (ydcbg5 d+.ks9j oy5y-6 jojoxzed 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/sx9v 4lb 0rzs+q. What must be the minimum coefficient of friction between the tvlbq9rs +x0 z4ires and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. The coefficient o, adz.ku 8gq ng /d45rlj(y1ymd ;o7aif friction between the tires and the road is 0.40. What is the minimum radius of the curve if ,(d;na .g5 izuk4dda 7l1 jygorq8y/ mthe car is to stay on the road?

  What minimum banking angle is required fvw2 1m w/ vtiju)*4+nxb yoyh5-p wv:eor an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s withouty/nwo w*vwv5u4j+)2-evbp1 i x:htym skidding? (Ignore friction.)

  A horizontal curve on a ( xl)luzn3yu( 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 -x g:a7hjeib0m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 af59dz chubp+ q dw+plm63k4; m is 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 oum 8+bfke u(xcjp5m),f a string is revolving uniformly in a horizontal circle of radius 0mm5p(ce,b)8xjuk u f+ .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, ab1o ,qof:o 6kvgz*xfe1d cb8 gm/ ,y+f 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 value in the zgo vd*o+ ef/b 8bm1gxf y6,co:1q,fkblanks)
(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 cons.ip8/kgh,k ovsk m2 6vists 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-kd3 8(zh4c5qp6x dso59cqcl0 tcdoi b5g person standing on the Earth, due to the Mopscdd6(t05o 3bq 5 lioqd4cc5 c 9h8zxon? The 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 massesh7 .h vx ayoia2510x;mb ds)kc is F. If the masses are moved to half of their h)yxa. bocm a5 d7h;102sxkivinitial distance, what is the gravitational attractive force?

  For a spacecraft going from the Eau4qk+h 0:8ii nt+kv o+otqt8crth toward the Sun, at what distance from the Eai++qontt8ku0i: q8ov hk4+ctrth 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 Moon ib b:tt3od. qxe:z8zey r z9p 8lui/v37s $7.4 \times 10^{22} \; kg$ 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, ndp-);quxw xzt-o v2 the Earth equal to the radius of the Earth. What is her acceleration due to gra ;uz)2 d, -nqowx-vxtpvity?

  The radius of the Earth is R. At what distance ac:p a+do97 )aaum ys)nbove the Earth's surface will thac 7 9+pum)ay s:n)adoe acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above j jcggn,))ey:its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceljg )en,:y)cg jeration of gravity on the surface of Mars, is

  At a distance of 14000 km from somz-21zrbbb uz )(yf m,ce planet's center, the acceleration of gravity mc bbfbzzru,- (yz1)2 is $32 \; m/s^2$. 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. The757 mt zfo80zqdg uyf; Earth has radius r. If the object is raised to a he uoz5t g8ydfm7f;70zqight of 3r above the Earth's surface, what is its weight?

  By how many newtons does w-tb 7ip6bww5rl0ukj:r20bk the weight of a 100-kg person change when he goes from sea level to an altitudbkwb 2u0rw6lkpi-7:0 jb 5trwe of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius-ay0 epwox+yb n c+ebm:4ve8f5nk h63 r. A satellite of mass 100 kg is at a point 3r above the Earth's surface. What c36w oav-y n+m4ebhkx:nf+yee5b0 8pis the satellite's weight?

  A spherically symmetric planet has four times twrl3ujikm gq,(42) ybhe Earth's mass and twice its radius. If a jar of peanut b4y)j r,k3iu mbq(w 2lgutter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclips()3or w7-qrn dk: si7i 1gz tpyyabg +(me0oz9e, the Moon, Earth, and Sun all lie on the same line, with the Earth between the Mow(r ds9ia ) z3egiyq7o1b (ptk:ogm+nzry 07-on 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 transportev 3* c rrh,dlxs(sv txuho)+,;d 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 thekg;g5 s8 wydi4 Earth (i.e., it just skims the surface of the Earth). What is the4dg8yg ; 5kisw 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., it just skyhjih ; j)x4z:ims the surface of the Earth). How long does it take to make onzh 4i; x)jyj:he revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit0 ds:ya;rh1dc 230 km above the surface of the Earth. It is observed to have a perrdsyd 1;a0:hciod 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 a d yq8+po zfu1/r /f*opu)vr0jn 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 )ut d; n nfa1h)7ce0miorbits 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 plane0 s;: fiioeve4i-tc j.k u94lxt in nearly circular orbits. Moon A has orbital radius r, and moon B hxu0e:ktfjvo lii 4.i9e s;-c 4as orbital 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 isj 19jyjhg( yo. $7.78 \times 10^{11} \; m$ 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. Whatnh wu m*/o/vec obdwz/j:7 u38 is the average distauwu/wbvj7 :*ncome/ od3h8/ znce from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)