Is it possible for an object moving with a conslltw+52 1/tj9exr,xt wr.sc rtant speed to accelerate? Explain. ,.w5 s9cr1txr+twr/ ltxlje2

  Consider a particle moving with constant speed such that its acce31aab6dtcck9 leration of constant magnitude is always perpe9tackc 6bd1 a3ndicular to its velocity.

  An object moves in a circular path at a constant speed. Comparsi( yi*rh ;su13hm xlqvg/e0v**ghc8x*yep /e the direction of the object's velocity and acceleration vec he1 x*(u;8ehp*smivgciygl/ v*xh30 rq/ s*ytors.

  When an object experiences uniform circular motboz. 8 8guysl5ion, the direction of the acceleration58y8blo g .zsu is

  Consider a particle moving with constant speed such that its acceleratios q5x,rv4xr ,jn of constant magnitrjvs4rx ,5qx,ude is always perpendicular to its velocity.

  What type of acceleration dc+ iq; y*i)/ierdew4q)r hwj/oes an object moving with constant speed in a circular path experien wiw*e/r eryid;4/ci h)j+)qqce?

  What force is needed to make av*xg 3p(axq+r b9jvcp:v0on0 n object move in a circle?

  When an object experiences uniform circular motion, the direction ofsr-a*z rb sz4k.3zyf 2 the net fors3za4f sr*-.rkb yz2zce is

  A roller coaster car is on a track that forms a circular loop in the mktjc v )xvh)t nri/ccy qowt/k b/b71j() /34vertical plane. If the 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 ))x/n krvb1cmyjcic//v(j3 wtttbqo7k /)4h point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (radiuo 53fs )wj2ij /c,rhwrs = r) in the vertical plane. If the car is to just maintain contact with the track at the top f/ ,wwhrjr)ij 25 sco3of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-04mj8aytb5e13g ufx w circular arc until it is going straight up. Just as the plane is at its lowest point, the aem yb0gj5xuwf41t 38force 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 of radius v1o se2d4 6wst$r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curvevse.)4l ez8 a a,kcoww331zxp of radius r at a constant speed v. Then it goes around the same cvk34axp ,l1ws)8cez 3e .zoawurve 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 cons9 (-2mq yhaxzotant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal mz hoa9-2(xy qforce 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 wicn b2sz0wo18he64nwtstpx t-r -q(qvp )*+x gth speed v. If the road is 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 equatb1sq )p82+en0cg r -w q z 4*nostx6-thwpxv(l in magnitude to

  Two horizontal curves on a bobsled run are banked atq01o1 x7 4jfzfe)f qqf the same angle, but one has twice the radius of q f01jf7xq e1fqfzo)4 the other. The safe speed (no friction needed to stay on the run) for the smaller radius 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 consisbekl ;c pd0v.t-8+ftant, but increases upward from the horizontal. Coming ar ck;8ftdv0p.b + lsei-ound 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;f ag1jk/ (i nr+dl1u0lnoa2 oyv0mn3 object moving around a circular path to have both centripeta k+l1 0unald 2myorj/0(f;ni1oag nv3l and tangential acceleration?

  The gravitational force between two objet,oq r n6 ew:4ym+rt:i-zv,xpcts is proportional to

  The gravitational force bet ij13m y1pf: mkbk-w3obx:)atween two objects is inversely proportional to

  Two objects attract each other gravitationally. If the distancezc8g gp-:/ij 93 zahlw between their centers:ihwj3 /9cz8z g-pag l is cut in half, the gravitational force

  Two objects, with masses p20mfj(t) cvy$m_{1}$ 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 mal xm fr54mk58/b5zwco sses $m_{1}$ 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 gravitatiokig t g7o2/t rf*zi42ln.

  Compared to its mass on the Eart(r8 b )bo3f5bm0khocbh, the mass of an object on the Moon is

  The acceleration of gravity on2q)vb2.zpo grk+ a )us the Moon is one-sixth what it is on Earth. An objep.s oba2r v2kuz) )+qgct 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 weig;pz;f xzsr by2j;u0 y5ht

  A spaceship is traveling to t :qrfx x(grs7nnh)sny(;) hxd/,lbb 1he Moon. At what point is it beyond the pull of Earth's grxgnhqn)(r rf bd:/b,n l()ssx1h7 x;yavity?

  Suppose a satellite were orbiting the Earth just above jr,g yp +w)e4l1 fs j1ec39fmk9/rot rthe surface. What is its centripetal accel, fygel o/r rre9sw+jj1 9mkp)4 t1fc3eration?

  A hypothetical planet has a mass of half that of the Earth 1wpyys6g63 p sr/-pve and a radius of twice that of the Earth. What is the acceleration due to gravity on the p p-pw6s6 y/rsgv 31epylanet 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 Earth. Thk:g6 jxfjc6155e9dhjbbl3j4fz d0sl e radius of the Moon is on6cdx6f4j: ljjkdl 3ghb 0 5jz59f1esbe-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surfacejrvq;t3j ehymletl2bn;kx 1/ e 4/k;( gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of pla1jlqnb mke 3t;h(2jl vyk4;//exe;tr net B?

  Two planets have the same surface gravity, but; p:j.7bto m9;f*6zqwkoe tzc planet B has twice the mass of planet A. If planet A has radius r, what is the radi tje 9 zozw.7kcof;:p*;t6mbqus of planet B?

  Consider a small satellite mo9hy+g0n7)n,a o jd ydkk/g 1zgving in a circular orbit (radius r) about a spherical plane z/yog 0j9 k1y,nkd7)g+gdahn t (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellitj(u6jv7z*qg*v 8 ( gdbtc0pmge B, and rotates in the same orbit. Compare the two satellite(g8 d*7 6jbuc(gmtpgzvjv0 q*'s speeds.

  A person is standing on a scale in an elevrlot 8 rc086lcly6 s3mator accelerating downward. Compare the reading on the scale to tl c86y8l tcr l630sromhe person's true weight.

  Who was the first person to realize that the planets move in elliptical p:ubf-*1w g31ysmjd 5 d el h4uz7fc2ttaths aroundluzw e4j1t g sh*dt:ydm1f5uc f-2b37 the Sun?

  The speed of Halley's Comet, while traveling in its ellipticaltn j+zgl5* 6pq orbit around the Suzqlg6pt5j+ *nn,

  Let the average orbital radius of a planet be R. Let the orbital period be T. ,evh9xvh;vr/. ts1wh/bm: w/q i2q.o pv - uns What quantit/9r,nq2 x.wu w-s1v ivtmop q.:/;/hhh vevsby is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the gacp)) i/d: byt;f rm(lk5 8drkolaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If tc ;(yp5 8:fdm kkrr/)b ldi)tohat 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 deyd)f/vkbyyaro zb86k ki(be/ (d45k+fined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third kvb8iedz ybf(/b k(+r6k 4ok)ad y/y5of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.a 1jq7 v7pd(y+qpcu0j

  List the four fundamental forces in nature.l )4n5 wy: qp5wpz 7/in:bceap

  An object moves with a constrfd:nr,ti./ eant speed of 30 m/s on a circular track of radius 150 m. What is the acceleration of thetf n, ridre.:/ object?

  The maximum speed around a level curve is 30.0 km/h. What is th2 p3ety6uo55e metc57n9 gao ve maximum speed around a curve with twice the radius? (Assume all other factors remain u36eop2e oevnt yc a59gt57um5nchanged.)

  What is the centripetal acceleration of a point on the perimeter of a bicyclirr,g7rhq 6bbfh: q15 e wheel of diameter 70 cm when the bike is movqf6hbqhr5r71, i: g bring 8.0 m/s?

  A point on a wheel rotating at 5.00 rev+icnm / 8 nn*noe+svn+r;*yridjx 6z ,/s is located 0.200 m from the axis. What is the centripetal accn+j**+;n+nco8 nn esr y/vi6i,rxzm deleration?

  How many revolutions per minute must a circular, *shn (arv*m1brotating space station of radius 1000 m rotate to produce an artificial gravity rn*habm* v( 1sof $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius *l9ih/ rraenk fr9f48- lypw 6turn at 96.5 km/h. What is the centripetal force on 8lr6-yw9elnphk 9rf/* f4ira the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whf.b)f)/ aa- r;fuduht8y w t+virled 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 strinyd8urf w +)uft);havfb-ta/. g is not to break?

  A stone, of mass m, is attached to ap:,nh4x,cr m -fxfj)rux,(vp 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'sx)4mc, (hxnx r,p-ff vj:,rup speed at this point is given by

  A stone, of mass m, is attached to av0cw -;- /hkr9 sbttlk strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension s0 ;brct-v- tlh9 /kkwin 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 wi,w+cs(g e t60gu /ivvhen pulling out of the dive. W v6+(0evgw/, iutscighat is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in whi7kxd*rewgcl: m p3u/6 a:u6k gch 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.g k6/6d ce*xu7 wagrk3plm:u : How fast is he going?

  The maximum force a pilot can stand is about seven times his weigtfyo. p4jr 7bd8 + etj36;ch)n8ilcshht. What is the minimum radius of curvature that a jejth di3o7; rnyl j84be 6hccsp)8+t.ft 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 an 80-m radius horizontal curve with the tiret:5s o97unmy vs on the verge ofy tn :so97m5uv 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 surface.)

  A car is negotiating a flat curve of rad1 zxmm(0vmf nnh gw21 tpzp8.-ius 50 m with a speed of 20 m/s. The centripetal force provided by frict1wfnmnpzx mmvz 8- .1hgp02(tion is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat brt4q(0ifr)qzt 5n )0c7cwxl curve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction bet4tq0 5 rx lc)q)0w(irtfbz7cnween the tires and the road for the car to make the turn?

  A car is moving with a constant spee ng+0o4qs 5kemd v around a level curve. The coefficient of friction between the tires andkmoges qn+ 045 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 forazd,+r1/i,x:5( x vag pyee sm an Olympic bobsled to negotiate a 100-m ram(idxae: ae5gy1+r,p vsx/z , dius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 9k bemjksu;i p:s(6+gtnwoi +,r5e p- 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 smyo381lvgotv4)ey ( ppn,/ vof radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m5eucdor uhih;m(4uxy -;sq ,9 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 )q,d(x; duduuend of a string is revolving uniformly in a horizontal circle o,x;quu dd(ud) f 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 unif 3ld)vcj4mseh xgq2(* orm rate to a s)2qe*l 4ms3 d hxcvgj(peed of 45 m/s in 15 s, moving on a circular track of radius 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 0vy5j;;d3m5uhewi ab 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 forb rpe rt2i:c-*dtdn14ce on a 70-kg person standing on the Earth, due to the Moon? Thp bt*4tie:1c dd2 n-rre 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 sbutlnb,*6rh z8hj*4force between two masses is F. If the masses are moved to half of their initial distance, what is the gravitational attt ,sj*8b6rn hbh4ulz* ractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from thm) o 0l;xk2)ww.(yq-dc mlm jce Earth will the gravitational forces due to the0dl -lkw my omccmj);xw 2)q.( 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 ivae.;zuv v; :qz1h5 pys $7.4 \times 10^{22} \; kg$ 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 mxyd9c 0w x*nx+q(0zsic 0iw:above the Earth equal to the radius of the Earth. What is her acceleration due to gravityw(9sm0xc * z+wi iynqc0x0 :dx?

  The radius of the Earth is R. At what distance above the Earth's surfawmv fdy3g,p te4oa1umo5 39 / edt9kv3ce will the accelerat3w ea3d fm 34e gytvo,/5 tm9ouk9v1dpion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distan qld9pwe )dqyt+y ; wtv(5/m6nce above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compt/v6 yw ytme ld;()+ dqq9n5wpared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some plan6nm (tpc +kvw/+rvyg:et's center, the acceleration of gravity i+gr6v ytc:/n(wmkp v +s $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the surfacvf9 fyk+c ko7.s6l /vw*21hyl c-ihtee of the Earth. The Earth has radius r. If the object is ra9-k. wivstel y*2h1k6yf l7 co/f +vchised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 1hpj/ aod2;wn i)-u n+u00-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radius of the Earth is - u/un;pw)hjod+n a 2i$6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a poinc+pl5/c tmcoqz (4kss)0 j5w zt 3r above the Earth's surface. What is the sat /+wzp5mc kj z)q l(4ss05otccellite's weight?

  A spherically symmetric planet has four times the Earth's mass a xm 8wcq( okl;2+lqh7and twice its radhxo clmqw2l +aqk 8(7;ius. 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, an *xc. mwz ;+esduy)8ncd Sun all lie on the same line, with the Earth w;c mz*y c8.)+exdusn 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 is transported to the Mois1f wr c+/dex;d1*(zd4/ b jijwoa(x3ht;wn on.
(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 or 7x l5uv2rwf nnwr0w53bit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the saw nn32xu 0w5r7 frvlw5tellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth w;t *,n)i j6aqo8sm5j;ocmsd(i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean ra,imo*d6);8 j5nsqm cow at;jsdius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earth. It is o,nc))142k . mjht ebn:h mmrf+c:gj bvbserved to have a period of 89 min. What is the majnv hcrgb)4mht k+:ebm),j:f2cn1.m ss of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter o2lr9 bii80xth f $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orbits the planet with a radior/;c5tnn us-dn; b9o us 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 Axo tpk;:j/ 6i)eq d:fc has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to e/ kcjt6;i odx)::qpfcomplete an orbit?

  The planet Jupiter ibv*l k 5ua.h1fs $7.78 \times 10^{11} \; m$ 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 averagzq 28cx*8 6 ,awyk net zuyv/j4b)iu+uqb:.oce distance from Jupiter t4c82bwvb.eqy xkj*:u/ +ai8zqo unt u)6 cz,yo the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)