Is it possible for an object moving with a constant :5v+fie-(pd 8jwjhbc speed to accelerate? Explainj chp:8 b(jie- d5+wvf.

  Consider a particle mov*g,kh)0x 7ia xkvz 3hxing with constant speed such that its acceleration of constant magnitude is always perpendicular to itagzxk*xhki 3 ,x7 0vh)s velocity.

  An object moves in a circular path at a constant speed. Compax98f gy(uk e4lre the direction of the object's velocity and accelelg84 y(f eku9xration vectors.

  When an object experiences uniform circular y0aw6k7 y vi*kf/) e4a sxmtuo88mu i)motion, the direction of the acceleratwya*iosey i/48f70km)t8ma uukx6v )ion is

  Consider a particle moving with.lv8nte 0:c kj constant speed such that its acceleration of constant magnitude isj0tne vl8: k.c always perpendicular to its velocity.

  What type of accelera)ely )urdqc1z ++* :4 zpoeufxtion does an object moving with constant speed in a circular path expep1:zu4 * ucedzr)xo ylqe+ +)frience?

  What force is needed to make an object move in a circ/ax-0jzetqx + le?

  When an object experiences uniform circular motion, the dirqx)c vc4 5bg-jection of the net force is5 bx-q c4gjv)c

  A roller coaster car is on a track that forms a circular loop in the vertig6k h zw xwkw(h)5* +uh;dhji4n9dqbz4r /o6fcal plane. If d4x6 hdkhnbo jfgh+ iw ;/*ur4 zw( 59qhw6kz)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 point?

  A roller coaster car (mass = M) is on a track that forms a ci focz/9i4 g(081qphr wq9aod .cckkf1rcular loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of thf 1qr(oq/kp dig90 k4fc9o.zc h8cw1ae loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive thenfq0ft r5-8vhtw molnds (c/(7 follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on him fv rlf/78(-0otdqwst h (c5nm 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 cub w qzbqa.3:l4rve 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 radg7q+ hn*rq z7n (xeb io4wp*z7ius r at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal f n*zz7n 4eho+wr*x( gq7 iq7bporce on the car as it goes around the curve for the second time, compared to the first time?

  A car goes around a curve o4 4ii:tdd tms; tmaj6.f radius r at a constant speed v. Then it goes around a curve of rst6.di4; 4ijtm matd :adius 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 radius r with spee.fzpm:bec ga)(mth **d v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal h*m e:b.f gp*)tzamc(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 atslg: *7/ boxva( aeiof+ 9.gxc the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the runlf.x7bosg : gic a9x( *eao/v+) for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn u dqh:;af09 qqon the Olympic bobsled track is not constant, but increases upward from :0 ;qfqu9 adhqthe horizontal. Coming around 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 object moving around a circular path to ha7sc ;6, unxysra9(4tioono. xve both centripetal and tangential acceleras x.xou in79ns,4oya(t;6o c rtion?

  The gravitational fo/k:mst -gih- brce between two objects is proportional to

  The gravitational force between two objects is inverselygw6ui ; dqkh3+ proportional to

  Two objects attract each other gravitationa)l(tti f*-/ fdrc jn7llly. If the distance between their centers is cut in half, the gravitational flfcn(/i* jdt l7rf) t-orce

  Two objects, with masse)6 -0jtnadcrp 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 mao9,zlsc43rr ow hx p.kz7lb66sses $m_{1}$ 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 gravitation0w42outq lu4v .

  Compared to its mass on the Earth, the mass of an obsa*whq cl (ve ndz:xo1f)041pject on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An obf;6te6qq )d5ath5 fb kject of masf;6t6 aet dbh5f kq5)qs
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, ts,71cv1 5elo.fvgtms us() obhe rocket's weight

  A spaceship is traveling to the Moon. At what point i3kje5 e)bnh :hs it beyond the pull of Earth's grb:5khj 3ee h)navity?

  Suppose a satellite were orbiting the Earth just above the surfa-/5 wxyz z8ng0 a6uwmm ngk6d9ce. What is its centriu 6w5dnywgxamg 8-znkm 609z/petal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius of/ ah w pf9mq6zz,8x-dyj-6ayn twice that of the Earth. What is the acceleratioa8x6a-y9- qzw/hp6nfm zy, jdn due to gravity 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 r x8p6wj-tt*q0nl jt+mc 3 v2vEarth. The radim-tn0 x3rvqp+6tj tl8 wc2 jv*us of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the sdhi9.d m.xu.t ame surface gravity, but planet B has twice the radius of planet A. If planet A has mass m h xdmi.9d.u.t, what is the mass of planet B?

  Two planets have the sam-r7 kg6r/.i c6bdv ceme surface gravity, but planet B has twice the mass of planet A. If planet A hasm6 7drcgkre c/-bvi6. radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius)o1/zjeytk1g;jlh( mp5p g, u r) about a spherical planet (mass M). Which expression gives this sagpmy1plk z5 (, )tuj1j o/eg;htellite's orbital velocity?

  Satellite A has twice thefn)l2045;mzgso qxnqez ),y a mass of satellite B, and rotates in the same orbit. Compaz)nfl) q0,2gma54 qyx ;zonsere the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward.oon 7q. +uq/le Compare the reading on the scaleq+lno/7.ue oq to the person's true weight.

  Who was the first person to realize that the planets move in elliptical pazt*cx6j.dl)vh . lurovkk0( w : v6wd8ths around the xr: o(vjuz vkwt .0*d6l)v6l8k.w cdhSun?

  The speed of Halley's Comet, while traveling in its elliptical orbit arou r:ftf-ej z-zg8 5t.find the itf ft-gz 5-f8r.:ezj Sun,

  Let the average orbital radius 7gg wft4qq f4zo.m d zs,jk274of a planet be R. Let the orbital period be T. What quantity is constant for akgzjdz mg4 f wo. 7qfst7424,qll planets orbiting the Sun?

  A planet is discovered to orbit around a star in t8*4ok4w cmdjnhe 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 tha8mwjc4ok* dn4 t new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as one "astronomical u5 :zcbkir9xwg;th p.+nit" (AU). An asteroid orbits the Sun in one-third of a year. What is +kt:; czg bi5xhwpr.9 the asteroid's average distance from the Sun?

State Kepler's laws.*r7 kcenyar9(

  List the four fundamental forces i sckb u8kh04fn2ud /1d /bbcw:n nature.

  An object moves with a constant s/ *dbrword0xz:eawym :n54 (z peed of 30 m/s on a circular track of radius 150 m. What is the accelerati4rz r0d/ xaobeydwmnz5*:w(: on of the object?

  The maximum speed around a level curve is 30.0 km/h. v08jrc cy0vbn1/ 0pqgWhat is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchanged.)vn0cg1 /qypr 8v0j0cb

  What is the centripetal accelerlm/n- 7sj:qmn )oy*eo ation of a point on the perimeter of a bicycle wheel of diameter 70 cm whe)j -7 nmosl:nyq*/ moen the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5. el 7s(j3*ajbd1nry:g1h s d (b76h1yng6 tpyz00 rev/s is located 0.200 m from the axis. What is the centripetal acceler b h6y*6ys7yn:g(1dhd 3b1jra npst1ejl(gz7 ation?

  How many revolutions per minute must a circular, rotating smmk9),w+wcr2c 2*s lsa s*zwypace station of radius 1000 m rotate to pr92* mrs,slm zcy cksww2+)*a woduce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around atz5bth h090 hj/hyh;a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcycle? 9 zhha/y;hhj50tb t0h

  A 0.50-kg mass is attac4wo4 xy* q8dbehed to the end of a 1.0-m string. The system 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 st y*eq8 4dxobw4ring is not to break?

  A stone, of mass m, is atfnvpn :i p6-sb) 8lq/ctached to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in the stringfnc p) vli:/ qpb-ns68 is 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 inxk(d wu*6czxx 4q2 yb646ivyg a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 tik6cz4u(g*w6 xy2qivxyb 6x4 dmes the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experieh pet .(jhk,2ences an acceleration of 4g when pulling out ofkhej.(pth, 2e the 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 the center of the loop isxj-71ldu y;v;5z h. g: e:hsxnk qxz/w beneath him) of radius 3200 m. At the topnk /delvzhxg :jzq.s-:7;h1x5w ;xy u 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 h.cgceg9 - (zais about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, gc g(.-c9ehza can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with the tirehqx(9;*rbw xqxw:vo 3s 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 9xb3v:qxw (;o*rhxwqtires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. T0tx dm8d4ow-2l 6t z,c0j krcahe centripetal f8mk c- wdd 0ozt2j,lac 406rtxorce 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 a speed dy9 os6 p);cai)f:oorof 14 m/s. What must be the minimu:)r; ps9oo af)6 ciodym coefficient of 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. The coefficient5r1k+)f wi/fbpat(h)yy uu r4 of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stau r5yt+k)(baw/ir y4hfu1)fp y on the road?

  What minimum banking angle is required for an Olympic boxc 5ggdj3lmc8iw 4h43*5xmnb bsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictid gcbi*mx53 4g8w4c3hxm njl5on.)

  A horizontal curve on a bobsled r cx;8y+3oyl hx; unn1gl7td1f un 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 m,7q- ty v8h3gnco*g ba; banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked r buh,7qa1 8lrat $45^{\circ}$. 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 unifof)dx8a uo3: ukle08zirmly in a horizontal circle of rax ku8iz3 au) lo8e0:fddius 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 accelerate jo7imdb6spw ub;a;)3s 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 ;bibd;o3pa )jus67w min 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 prohl0 awbtsi2,h *4evy)j5x4m g ton 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 st b5e-tv ikx6j/f:ge2 aanding on the Earth, due to the Moon? The mass of the Moon is tg ax/kjie:e-v256b f$7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masses is F. If the masses k6rn3+j1 moi:;f r fekare moved to half of their initial distanc3r1i rk;:e mnjo6ffk+e, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance y /c)m58ic5txchg irec+ lh t)+. spv3from the Earth will the gravitational forces due to the Sun and th tv+y)tml5hreih .cs8x/ic)cp3c+ g 5e 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 -o4kv ,v) :nqr* xvnyois $7.4 \times 10^{22} \; kg$ 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 ay(s k jcc1i09v0hh eah/5 8wjvbove the Earth equal to the v9a5e h cv (ch1w/0sj0 hy8ijkradius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At dd1t fr3 itt -7gq)k,hwhat distance above the Earth's surface will the acceleration of gravity b 1-qk7 ,g3dtt)hrdftie $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance abovb ygx9wc4x t+2e its surface equal to 3 times the radius of Mars. The acceleration of gravity obwcx t+x 24y9gf the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from s7fxv zvgp95ss15h6zarwa8 b7ro7fo. ews( , wome planet's center, the acceleration of gravityo wx71fba 5szzvrg7fps 9e o,7( rw85v6h.asw 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 d1z+e0eiqbmff20i;l on the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's 20izee1fmd0bf+ l;q isurface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when.xa,0l,p aghaa1. afaw7t5xu he goes from sea level to an altitude of 5000 m? (The mean radius of th,gl0 aa1xp7afx..t u h ,aa5wae Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 4i/zxdc e;4t ckg is at a point 3r above the Earth' xe /44tc;cidzs surface. What is the satellite's weight?

  A spherically symmetric planet has four times the zgjni n:czo9c 6/ (s0fEarth's mass and twice its radius. 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?cfci(zz9s nn/0j:og6

  During a lunar eclipse, the Moon, Earth, and S,5ihmsi z. 9fz o779 (pzliqubun all lie on the same line, with the Earth between z si5f,h (lzbm.io97 9iuz7qp 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 thewwsl1z3 q(c gs0g nvli669 zuh3nq9w4 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 the Earth (i.e., it just skimai+ :.6ozaou 7i7 bshna/+lgjs the surface of the Earth). What is the speed of the satellite? (The mean radius of t+ l7i.azo aij7+6oh b/a :unsghe Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., i;vqzjrzq g4 1z, -h lrodw 78zrs4j9)kt just skims the surface of the Earth). How long does it take -4r dzh4srrj) 1jzowg 87vqq9, ;klzzto make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular d : mevuf37l8w( pd3/a4ij dgsorbit 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 radil/3e:73g4v(idddf8s pj m uwaus of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, t/ ;+;hrf:q55ovr bvpmxblw 2has 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 th c:*bbgwq6e5 ue 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 b7 -) +vkk0tstubt wx6nearly circular orbits. Moon A 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 coswkb6t -0utk+txv ) 7bmplete an orbit?

  The planet Jupiter iss.jsx* (,u3wqq sp * ad5mb(hd $7.78 \times 10^{11} \; m$ 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 averag y.a4fav(g ab6e distance from Jupiter to the Sun? (The distayafv 6b.gaa(4nce from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)