Is it possible for an object moving with a cons 7+9mkr0vp bgatant speed to accelerate? Explainr0g vam pb7k+9.

  Consider a particle moving with constant speed such thai2g9j 7x.cz5 tznj;z.hjrp2 et its acceleration of constant magni59c.irej7 tzz;jj ghzx .2 2pntude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare t5ebyzanm-je-r. cpn -)u4yrd*j hx)7he direction of the rxpm7a)j -d-yh .- n )uc* 4ne5ebzyrjobject's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the achl;s-/igbwn6( ji3 c,d9s gvxl f29lkceleratio6n9s-hf2;bslg gdvwji 9 il3 (/,lxkc n is

  Consider a particle moving with constant speed such that its acceleration of iaqk d 6o4pkj( qugv5sn*8 ,0pconstant magnitudupipq o06a4nk*v5j8sqgdk ( ,e is always perpendicular to its velocity.

  What type of acceleration dof53n ydkp96vya mat50 es an object moving with constant speed in a circular path experience?mv 50ankdty y9 f6p3a5

  What force is needed to make uh ipe,)0j)xme rg-0muf1:;cp ju4ag an object move in a circle?

  When an object experiences uniform circular motion, the direction of the net dfp8594lwcm)ia*1ilnat8 p aforce isp*tiapnl fl8)mad1 a4i w895c

  A roller coaster car is on a track that forms a circul+g /.- hqfanazxc(76ajq 6hvbar loop in the vertical plane. If the car is to justb haxhc 6jq/agz-q6a+ (7n .vf 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)rbu9riemws*55k( lka f1 s)y. is on a track that forms a circular loop (radius = r) in the vertical plane. If the car rs5ksfk*9r el .m baw( )51uiyis to just maintain contact with the track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a v(hkjq3i e 89k,nxe 8bkertical dive then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force kieh8 (e qxkkb3,9n8j 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/tzb,*qa*of e of radius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a cur8: mcjx 5d ws*z6pgpp9ve of radius 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 :gw8pmd*6s9p cx5zp jaround 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. Then it goestd(z8d52p )yj r ;iy(lxueo 5f3 vnjy; around a curve of radius 2r at speed 2v. What is the centripetal force on the car as;55 tedvylynj82j f(o3 pd(xr z);yiu it goes around the second curve, compared to the first?

  A car of mass m goes ncx y.yb ad86.around a banked curve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal forny..ay dc 86xbce on the car from the road is equal in magnitude to

  Two horizontal curves tf.z9d6hu4zg on a bobsled run are banked at the same angle, but one has twice the radius of the ot.t4g 6 zz9hfduher. 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 tra*:)qif3uxattfd 6f y- 2uull) ck is not constant, but increfu a):xdu )-y6f2q3utlti f*lases upward from the 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 movingmna0k c4dw qi:5z-d.pop v;nd xx:h c.mfo ,,6 around a circular path to have both centripetal and tangip x 4wo.,mfd :- ;nh.x6z:o5dnc dqac0pkm,v ential acceleration?

  The gravitational forpc: (ct6e fuv)ce between two objects is proportional to

  The gravitational force between two ob;tl 9zib0nt; ejects is inversely proportional to

  Two objects attract each other gra j yo+5lv i*+1ltwix7:ymciw7frdw ;:vitationally. If the distance between their centers is cut in half, the gravcr ;ywjx:l+ 5v7w1wtmil+ y7idfio*:itational force

  Two objects, with maxt.7w uaw:4irsses $m_{1}$ 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 mat r* nl5/ t 4dwer9m6t0(z eng0lwnn btncx23*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 uh i7y0 ,pvl016qhthxmg;6lefa r61 k aniversal gravitation.

  Compared to its mass on the Earth, the mass of an object on themkxp 5es652pnc3z+ /sgs j5nj Moon is

  The acceleration of gravity on t8rgsz1a;c5 hya- (j5d a: ecsqhe Moon is one-sixth what it is on Earth. An object of massa dc5;(5ayae1g:r zhs q-8 sjc
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from t1 az 0a7,jm)6id. wemazcn fn6he Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the4lpd62 4x bzxs pull of Earth's gravitybxd4zs6lp4 2 x?

  Suppose a satellite were orbiting the 3p5 bie6 zic:iEarth just above the surface. What is its centripeti:iepi5 z3bc 6al acceleration?

  A hypothetical planet has a mass of half that of the Earth sm/w3s,ggvh 2+5jlkiand a radius of twice thl5sjgh/ m ivg,23+s wkat of the 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 the Moon il/v,t10ldp mh 04ln tus one-sixth what it is on Earth. The radius of the Moonl /,n t4pv100tdhllum is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice th.r jaz b z6m6(hp)*kgh we0fcrf5)a7ceu .e*ae radius of planet A. auakmrw. ejhep6a(.0*e b7r *zc)z 5g6hcf )fIf planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B ha .ax )kfi;poe6yq5.das twice the mass of planet A. If planet A has radius r, what is the rx5y.edp)akia. o6 fq;adius of planet B?

  Consider a small satellite moving in a circc7 b7r oh: 6phmee0th0yxpfqo h56rm5 ;yj+z 6ular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's or tc p6 6ym+05 5m7heb670h rzeoyhq;:frpho xjbital velocity?

  Satellite A has twice the mass of satellite B, a,f7rtgs h8uv3 ;ye4lqun q9gib 0)kp7 nd rotates in the same orbit. Compare the two satellite's speeds.ue 7,unq0f its4brvq9) 3;py87 lkhgg

  A person is standing on a scale in an elevator accelerating d l*-ics(-.vxwsd2s i aownward. Compare the readiaiw2s *(. -vlscxs -ding on the scale to the person's true weight.

  Who was the first person to realize that tr6 .x*/mofx f9jzcuhn4(. xie he planets move in elliptical paths aronm. u /o jz9 x.hx4ix(*efrc6fund the Sun?

  The speed of Halley'sf-i+e g0xg9fn Comet, while traveling in its elliptical orbit around the S9f-fgx eng+i 0un,

  Let the average orbital radius of a planet be R. Let the s l*pwhd8/j- 4g0v5hlm h.anut gt3j9orbital period be T. What quantity is constant for all planesl.gh4 uj nm3h9jla /tv-50 dpt8*gwhts orbiting the Sun?

  A planet is discovered to orbit around a star +b11 cyxf6fy o;0woh )8yymw 4ka d4asin the galaxy Andromeda, with the same orbitalx;wyy4fc8od)m6 w a4f k1o+s1yh0yab 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 new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Sun is defined as one "astronomicp3 h3wc p/hrq7al unit" (AU). An asteroid orbits the Sun in one-third of ahhrpw 3q3 /c7p year. What is the asteroid's average distance from the Sun?

State Kepler's laws.nk b7 sgn3o9*t

  List the four fundamentalj-.ouzi53f d x7pe/ ur forces in nature.

  An object moves with a constant speed ofn ww7;8+*c s3kcgwy gyhzu.c2 30 m/s on a circular track of radius 150 m. What is the acceler+zwsgcyhukwn* 32 c7;.cwgy 8ation of the object?

  The maximum speed around a level curve-i/yjf0h3ewo89 sgh/ p, c rym is 30.0 km/h. What is the maximum speed around a curh8 /yrypf3 9,i 0sh go-j/wmceve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal avzceb5(7.gl u 6p)nv;bnv7 m ccceleration of a point on the perimeter of a bicycle wheel of diameter 70 cm when lbm.ebzpn;)n7 v5vvc 7 gc(6 uthe bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis. *f1jbap0(6moana8py:0r(hbp2 zqwo What iso (aw h*bqa6bzo n m r8pj20yp0ap:1f( the centripetal acceleration?

  How many revolutions per minute must a circular, rotating space stgw7yh 1i b6b9e/rgb8w )zaq:oation of radius 1000 m rotate to produce an arg61b) h:qb/ 9g rob 7wwa8ieyztificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 k88u gv jdzy93 ilw*fp zn+l:ql6;lnx2w,fsk+g. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the motorcycle?l;xv3fd+wllg q8zk2 9 upsjy nl 8:win6*,f+ z

  A 0.50-kg mass is attached to the end of a 1.0-m string.h43pacdovz 86u fg+5bs 0k om0 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 th3 k5vs4ogmoc uh+p08a b f6z0de mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and su;tl*au9d+ *g 7;pli wy*d3im2z ynz whirled in a vertical circle of radius r. At the exm* nt 3lwdaszi u;+ y gp;7*l*du92izyact top 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 stone, of mass m, is attached to a strong string a j1s-z; i:ilieiqs sahx2* f/,nd whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3zfsqhisle1*-;x,j i :i s2/ia times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an q krx7hiu((vx7nz8.(xoda5l6 g xp+w acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plazrlqg h8 576pk xd(wx (u7 v.+xi(xanone is flying?

  A pilot makes an outside vertica4 ,:f3esqs n hr+a/lyhl 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 e,arh4ls3y:+ hns fq/ normal weight. How fast is he going?

  The maximum force a pilot can sta 7gc-p uqev8;0-yh snend is about 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 at a ec un;-0e8qs v g7p-hyspeed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve wit0h;r5 h 0ov.ytdd*vvpkdt2p2 h the tires on the verge of slh5k dvo2 dh0r;tpd0p vy2v*t.ipping. 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 fb,re2eys2 2j7iy:h wflat curve of radius 50 m with a speed of 20 m/s. The centripetal force provided by friction iy ifew222r ,eyh:sbj7s $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flatg28 7r/uoz7cm*ma.o*kq9a l zhly+kt curve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and t m*+u9aky8zkz* o/rlgq2 7 mc7.lhoathe road for the car to make the turn?

  A car is moving with a constant speed 28vd1 yzk) 6nsx3nh pjv around a level curve. The coefficient of friction between the tires and the road is 0.40. What is thjvnn86p 2 d)3x1 syhkze minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle ism+ln -ui+ eql8 required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s wm +nu +ql8-ileithout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is bankedh;qrpa6 yj z3( 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, bancar7*ewy 0 ,,dv+ wvvx9kw0ysked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 806r,:rj3 rmdc(s t)nb n 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 of a string is revolvijbyx:;ma bd 6t )51l.ph:a suang uniformly in a horizontal circle of radi1sb 6; pxu:ylmbj)a5 a:tah.dus 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 2cs)m g( 9- tfhaiz/oo2q fv9zuniform rate to a s(ohf92mtzo f)i-2c/g v qza9speed 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 proton6dc :1z l3fgpq 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 per *avq fvjp9b2xj lvd 6jn38w,,son standing on the Earth, due to the Moon? The mass of the Moon jvab 9,j8l*pfj,xw3nd q6v2v 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. I+t2f dd:,kub +cc r+tv)fz 8nzf the masses are moved to half of their initial distance, what is the gravv++ z, dzt2k+bnccr f) d:8uftitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance from thws0 67bbafg p+e Earth will the gravitational forces due to the Sun angb6sa+7 0pw fbd 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 vo 4 gs9a.8h -/gftj1 gw0kfptis $7.4 \times 10^{22} \; kg$ 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-wal4d8iajhels )1xg mnwm,/ t ,6dk" at a distance above the Earth equal to the radius of the Earth. What is her accelera hn84,ademdigwmj1,6 lst )x/ tion due to gravity?

  The radius of the Earth is R. At what distab 34hj(ft, vkezol5ngoj;4l* nce above the Earth's surface will the acceleration of g,v n5(o* otk3bj zejf44 llh;gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surfacex(g iu7 4h5urza gm fvwz6dqz1p475i9 equal to 3 times the radius of Mars. The accelera5u574ixz 4zhiq6p d9(avwug1 mzg 7f rtion of gravity of the satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 mxo9flvkv:ydd5 8c :4 km from some planet's center, the acceleration of gravity is:8 4cvldfk9vdx :ym5o $32 \; m/s^2$. 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 8 di*+pqyqn;hxcz z7 /Earth has radius r. If the object is raised to a height of 3r above the Earth'd;z yinzq +q*/78xpchs surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes fr3x853mi sm-ood h8wrnpf1 )gi om sea level to an altitude of 5000 m? (The mean radird18n of3s 3 xwgmi h8)i5o-pmus of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at a point 3r above +sjzgs690 13 nd n 6rveqx*xihthe Earth's se6*n vnx s6z+rj1 9qsihg0dx3urface. What is the satellite's weight?

  A spherically symmetric planet has four times thezym yp 0aa18d(6nixa4 Earth's mass and twice its radius. If a jar of y(6axa y amn1z80dp4 ipeanut 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 all lie on ths -rd3 0 vmcwin,8i-;h;dju ble same line, with the Earth between the Moosbd ;l-,riuwnc8v ;3id0 j- mhn 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 t(8b.a dly5 hx z*/lryaaw5-ajhe 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 skims tuf;m7czi ph7d 9j+ 8nkhe surface of the Earth). What is the speed of+ump7d zh7cf8 kji9;n 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 Ear))k2j) zwx6 rboc lgb3th (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean radius ofoj 2wxr))l c3bbzk6 )g the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earth. Itc4+cyz2 k-j qf24dtgq7ls/px is observed to have a period of 89 min. What is the mass of tql272/4fyc4qjz- xp dtk+s g che Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an -uak;,bzple z f+j 4n2orbital 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 ra14:ex ,fzwk/:wdvqr gdius 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 o ckro,l;d0(2 adgwna(rbits. 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 ,wd r ;dnl(go0k2(a caB to complete an orbit?

  The planet Jupiter i:2x6)5mzgd1 pypj l5 motrc5zs $7.78 \times 10^{11} \; m$ 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 yeart(: wgrz4ehjxc4k.p6:vi 9(o b bwqe5s to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth exwb 64e :zt.4:ij 5p(wqbh9cr gv(koto the Sun is $1.5 \times 10^{11} \; m$.)