Is it possible for an object moving with a constant speed to ;mc vvge8lc+ chq9a3 8accelerate? Explain. 3+ccv 9mcl g8h;e8avq

  Consider a particle moving with constant spemaa c4a ,rmo58 za(*zved such that its acceleration of constant m(*8 z aor5 ,vzm4caaamagnitude is always perpendicular to its velocity.

  An object moves in a4 i l;dm5,jpbz circular path at a constant speed. Compare the direction of the object's velocity and acceleration j i; ,pldb5mz4vectors.

  When an object experiences uniform cir3 +a kph17vlqv*huu-(u ynof/cular motion, the direction of the accelerati+f/( -o vvluh n13y7qka*upuh on is

  Consider a particle moving with constant speed such thatl(5/jwgmuh:h kl 5 j9m its acceleration of constant magnitude is always perpendicul :g95k5 mhlm(j/j uhwlar to its velocity.

  What type of acceleration does an object moving with constant speed in i a +mf-tcuvhgi94gbd+ bd.5 6a circular path experienchitg .d -a954bbf igdumv+ +6ce?

  What force is needed to make an obj9eurhh mp).u5kd7t 3*2ib8e pti2x vq ect move in a circle?

  When an object experiences unifi mqgu 46;w9c8c0 hdjfg)ci)borm circular motion, the direction of the net foriuwdc; g0jgfh9m cbi64qc))8 ce is

  A roller coaster car is on a track that forms qa9j b*lg qb7m64nxo9a circular loop in the vertical plane. If the car is to jusn79l a*qm j946qxbogb t 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 ( v5 gy8j4rqki8+38u*n wiedgw+l))l+ ccz m xvmass = M) 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 tx+g ng)u8w)y *cdz8 l vrl jmev qwk+35i+84iche loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc u8zxtr)bs 4reih7o 4 oe as.q72ntil it is going )xee84r4 t 7soh razqiob.s72straight 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 8 o7i )3q ,j fwndq/c5dw5,1 meumnoztof 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 con78yhv (whlocu5 wb 54kstant 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 second time, cyw vhl4 k5b u7o(whc85ompared to the first time?

  A car goes around a curve i. -b/q4 )cxcwln0jkq of radius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. qci /xc jl)w.k0n-4bqWhat 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 o ct2l1nkzw0 pgr/j*b7 f radius r with speed v. If the road is frictionless due to ice, the car cpg0nb /wrz*t k j127clan 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 the same angle, but 2xmyg z)+f0 c0 1fecdjone has twice the radius of the other. The safe speed (no friction needed to stay on the ru1m 0zfc ) f02+jxdcgyen) 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 nuka0k)abg41rkf5uy) tx -n * track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower - )nytk)0akbgkua*r5xn 41 ufcoming out of the turn. Why do they do this?

  Is it possible for an object mov-djx u)7 n5kls 26gpiqing around a circular path to have both centripetal and tangential ac5k p x7ns)lg ud62i-jqceleration?

  The gravitational force between ttpo-myj8 y( 6cwo objects is proportional to

  The gravitational force betwext/nvkxqjx 5g fw4 6;0en two objects is inversely proportional to

  Two objects attract each other gravitational,/n*od )fjk1inys8 gshif- /nly. If the distance between their centers is cut in f)jihs*d-ky /sngi/1on8n ,f half, the gravitational force

  Two objects, with mas q-deut00e3tf ses $m_{1}$ 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 pqn j8xa)jdi m 6 6scd9xee897$m_{1}$ 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 gravig)dxxp/yv +0ibp6 8vh/3 js/cyzj/mjtation.

  Compared to its mass on the Earth, the mass ofz tb hqmeit(5(uj1 2y),(aubn an object on the Moon is

  The acceleration of gravity on the Moon is one-sixthob 4ju-s)xe/e8 pal7g what it is on Earth. An object ob e /x7g 84-psoe)alujf mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Ey yapc5 pj,z/)wnhx4) arth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what pointbdq a8)w*,qcolos 9kx h,/flkm ,3gr/ is it beyond the pull of Earth'q8lx)kgm/whq3,or,ka/* s flc b,o9ds gravity?

  Suppose a satellite were orbiting the Earth just above 0dof; l1nka.c the surface. What is its centripetal acdla. 0;on1ck fceleration?

  A hypothetical plane o( x uo-c0way7ofid3ui( z/t-t has a mass of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the (7i(ziuxy-0 wto ou3 /a-fodcplanet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-si( ai:6ysk.b j841fi/-wyvvgskt-wj nxth what it is on Earth. The radius of the Moon is one-fourth that wi61y :yba8s-sjvk4wi/ fng(vj- .tk of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravitmf jpuk3f;lerjz9 q. w33*ha;y, but planet B has twice the radius of planet A. If planet A has 3f3j azk9e.*w rulpfmqh3 j; ;mass m, what is the mass of planet B?

  Two planets have the same surfa - kbkujy*(0joce gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of-(k jkj*yu0ob planet B?

  Consider a small satellite moving6a,xitby .vx. in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital velocit6 . v,xyiat.xby?

  Satellite A has twicnk0mm1z4 8svsjskrb y-1p/p+e the mass of satellite B, and rotates in the same orbit. Compare the two satellmr1j8n+4ssvk b z-y kspm/1p0ite's speeds.

  A person is standingxnx /9:woy, ej on a scale in an elevator accelerating downward. Compare the reading on the scale to the person's true weightojn, x9yxew/ :.

  Who was the first person to realize that the plapcvvx(zk q)h8 k6sjz07n /mp7nets move in elliptical paths around tpnsc(zm7)hxv 7 /q8p6kkv j0zhe Sun?

  The speed of Halley's Comet, while tr/ebapf 7 s(muyvw08 32nj7chjaveling in its elliptical orbit around the 3u p h0f/e 7j(bnjcam2ys87wvSun,

  Let the average orbital radius of a planet be R. Letjzx/0vwk 43+lbg t/ pj the orbital period be T. What quantity is c4j /jx30g p/tb zl+kwvonstant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromeday1diy5 fp 9-q) dc(r w;n:utrfwpr v.8, 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 r(q:9w 8pc.i w yv5 df d1f)-ryrt;nupperiod of revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun inv:ttbn+4ldniy .4n8 a43 oibs defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?:baly ibi.vt3n4+onn4dt 8 n 4

State Kepler's laws. /gc 7 mism/ n-cr8it,kcm/;gq

  List the four fundamental forca -qprkye301s.sw*o.a;7 nct4a bjr xes in nature.

  An object moves with a constant speed of 30 m/s on a circular tram-nd 9a2a:kx xcg79cm ck of radius 150 m. What is the acceleratiok9 2-amcxdnm7g9 :axc n of the object?

  The maximum speed around a level curve is 30.0 km/1m-06e0txj fhe2b cmudl l99h:l1. e iiamg+qh. What is the maximum speed around a curve with twice the radius? (mjtuil9e bdha. lh0011: g-+9exmmcl i f26e qAssume all other factors remain unchanged.)

  What is the centripetal acceleratio4llux zuq.y-7eb wn(rjmu ;).n of a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike is movinl. ru(n. bxulq)ej7z my-w4;ug 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/fxu,tsq55.nl s is located 0.200 m from the axis. What i x.su5,5ntlqfs the centripetal acceleration?

  How many revolutions per minute must a circular, rotating space station of radiu .guq ;d(mf8uus 1000 m rotate to p;u8gmdu.u q(froduce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mh o(d18qeb3f+8zs lhqass of 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcycl8dh+o(l1qe bq3z 8s fhe?

  A 0.50-kg mass is attached to the end oa2 k akjp-,yr5f a 1.0-m string. The system is whirled i 25,aarjk-yk pn 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 is not to break?

  A stone, of mass m, is attached to a strong string and whirled in -, l/a.zut5x 6;wecauzr6lp z a vertical circle of radius r. At the exact top of the path the tension in the string is 3 timea5u z; -xzzr6atlp,.6ce wl u/s the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is at1 7;6c- gsfrnwbq xe2h-io cbn8en* 7mtached to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the paqbcnhbn8w*o;sr - 6i7-1xn 2f g7eecmth 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 exper 6e + yous0nq85v;ykzfiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flyis0u;yo +en65vfky 8qz ng?

  A pilot makes an outside vertical loop (in which the center of the loop ipo (l6:mb;lif *g ix,5gza6k jmon97ys beneath him) of radius 3200 m. At the top of his lo9x ;oj 7lp:n5bi,g(zm ykaf lmig6o *6op he is pushing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a pilo0wkr tdg , t9ifn;y;g)t can stand is about seven times his weight. What is the minimum radius of cur wg)0g ydi9rf;t;,tnk vature 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 rounds an zkb1.kdiw 0aeo 3 -lo380-m radius horizontal curve with the tires on the verg bl3-zk0keoaio3d1w. e 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 surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s.cc6oo 5q: -ls7exv0b/h. wsla The centr.wco-hxvs/l6l5b 0a e c:oqs 7ipetal 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 of radius 50 m at avkl)kahr7sfd9) n y ;8 speed of 14 m/s. What must be the minimum coefficient o9n8rya hls;d)kk7f )vf 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. Th*k+k gosipet7261q vwe 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 iw* e+1ko7vgq stk 2p6road?

  What minimum banking angle is required for an Olympic b ny t/5-lj8nwtu8pu( pobsled to negotiate a 100-(njuynp-/ uw 8t pt5l8m radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is qjx hn1np)):jbanked 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 ol +idbqja)2 p6bp t-pf;,)kdbfly2 q(f radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked a4wm1 low cm(;ay+ 4w dtegx1j)t $45^{\circ}$. 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 un gnrn8eka) 6/ +w5h; dyqk.vxeiformly in a horizontal circle of radiusn6 q/5era 8)+wgykedkxn .;vh 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, /m e7lphwma1 6r6mr*c a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular tra1 arre6p6 *cwmm lh7m/ck 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 prot99kv +ib4 hprjfm,if.on 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 pers(ypndyecrf -9 +;fa:ton standing on the Earth, due to the Moon? Thr+td;eff9p any yc: -(e 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 masses is F. If the masseswgfpp 5bj majm -8h;-c(j:q p.lm+d+r are moved to half of theirm;:5prbljgh+(m w a-c qm. -f8jpdpj+ initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, r6;x1nhgap) cagpe96 at what distance from the Earth will the gravitational frg ) h6apxge9 ;pcan61orces 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 *wcew *o;e9ah$7.4 \times 10^{22} \; kg$ 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 ant/fcuj2 p2 1ybove the Earth equal to the radius of the Earth. What is hept/ f2uj cn12yr acceleration due to gravity?

  The radius of the Earth is x hlzlrtm;+v pv3.*.rR. At what distance above the Earth's surface will tz*v.v;t.3+ rlpxhl r mhe acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircledr4w ww 35tn0bs Mars at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity ofd t0r 5www4n3b the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's dny to)e:07 qt av)cs +if4dh2center, the acceleration of gravity tidd0 ny7)atfv q4s )c:2eo +his $32 \; m/s^2$. 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. The Earth has radi .royuw+ /n( +bsmipg0us r. If the object is raised to a height of 3r above the Earth's surface, what is i i n++bgy(w0supr.m/ots weight?

  By how many newtons does the weight of a 100-kg person change wjdqnl9z d1 9d+1xsl+dhen he goes from sea level to an alti+d+ l19dd sxl1ndj9zqtude of 5000 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite o j7np2a(ex ,zrf mass 100 kg is at a point 3r above the Earth'z,xe(7rpja n2s surface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice its mt p()8;z3/rkviwp pr:ln, +u1q zlvvradius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it ml: pq )p;(ruv8/i,vv 3r+1 tznkpz lwweigh on the surface of this planet?

  During a lunar eclipse, the Moon, Ear gqg8 q-kr /lkx)u3.wfth, and Sun all lie on the same line, with the Earth betweengkl8 .-qxgw/)qfurk 3 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 transporte3cutf )v 4bs+q -gj l6izbw75x 9xlqq9d 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 o/:zol6mhk8rofi i7- hrbit about the Earth (i.e., it just skims the surface of the Earth). What is the speei- 8k lfoihohmzr 67/: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 t appbm9o q50,uhe Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolut50aopq9pm u b,ion around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orb6nvbs m d;d.vw* py6r.it 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of v r s;*wd.nm d.bp66yvthe Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter opwynh 9kn u2c54a 3vm9f $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jubomf90esq4 *rpiter orbits 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. Moon A has or0w38u1bxa.;y xbpx* hzw4efd bital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one p 1;*x3y dx4efxwb uaz bh8w0.orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter ic)zgmt i8 x22r83lces s $7.78 \times 10^{11} \; m$ 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. Wha837 o-r.ri9g 2p+fy)xum uykbg5 s unjt is the average distance from Jupiter to the Sun? (The diurjrb 5.9fk7sui 2gxn g)umo-p8 +y3y stance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)