Is it possible for an object moving with a co0 rc20av ulf)s w2m6lrnstant speed to accelerate? Explaiwcm6r u 0vla )ls202rfn.

  Consider a particle moving with constar 2t6u.1xylrs f fw:40m1k lz x/rol;5 kz0wtint speed such that its acceleration of constant magnitude is always y2if;xrkr w wl 5xsz0mk/4:.6ztf10lt ou 1 rlperpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare gfcl,6kar6 8 athe direction of the object's velocity and ac c6fka6 8lrag,celeration vectors.

  When an object experiences uniform circula*b(t5 5f5 )qubaodzf rr motion, the direction of the acceleratq b5ffr5d*t)zu5(ba oion is

  Consider a particle moving with consof.:+tb5z;isfd9:c5 rr ugk ctant speed such that its acceleration of constant magnitude is always perpendicular to its v irt.kf+ f9dcc 5zus5b:o;: grelocity.

  What type of acceleration does an object moving with constant speed in*.cvhy4v8g- zjjs v9s a circular path experiencejv 8shjvz-.v9s y* c4g?

  What force is needed to makj9ms 22uob qrvl+i7 u9e an object move in a circle?

  When an object experiences uniform circular motion, the d6-p x7eu5xi+tty -eslqc2k3 sk1 ze4o irection of the net forcsc6qkyo5xlt4xs 3i1 kp-ut+e e7e2z -e is

  A roller coaster car is on a trni83xo7euw t 6ack that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is 3wu7 n8 toe6ixthe minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular loop (ra fuw(dnw+a0cddb 75xt x+27j adius = r) in the vertical plane. If the car is to just main+0fwjb d ca7xa +dx7tn5wd(u2tain 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 vertical dive then follows a semi-0hki363vm)a9 xh17f vy,x ed(yzy twkcircular arc until it is going straight up. Just as the plane is at itshy d1kz(xk7y)w a3,mv0 i9he6 tyfx3v 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 of radius j++w65k q8u bm,krv7lyl z sv5$r$ 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 cnwis .wh0:x vv;lzi4 +onstant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on v;+zl4. wih:xv 0nwis 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 constant speed v. Then it goes ar ;ij9z qaslbg jy,:r9)l0g;o found a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes aro;oqjf blgjzl:gr99s ,);iy0aund the second curve, compared to the first?

  A car of mass m goes around aboj*: gu*sm7 b 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 sb7 j:*omg* ubof the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at t vb)frgk6hk ie7h z/0/he 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 curve is v. What is the safei6b k )k7fhr /0hz/gve speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constantpvyf8pcsh* p/51 41kydjq 7bl, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then goy48hl1 qf pd7/1pk pcjy5bs*v lower coming out of the turn. Why do they do this?

  Is it possible for an object moving,qujs*bs01:xdljmdc f :n.k( s gy+d0 around a circular path to have both centripetal and tangential accels:j0 fy sgd .d0snjdb 1k*(+,:qclm uxeration?

  The gravitational force between two objects is proportional to4 (2loiu 1whad

  The gravitational force between two oxoch, - 4bi6jlbjects is inversely proportional to

  Two objects attract each other gravitationally. If the dista-v0o-shmfy1 qnce between their centers is cut in half, the gravitational foos--vh fy qm10rce

  Two objects, with max5pb u(+,ed 7ie(znm l8bamg(sses $m_{1}$ 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 masseoabu5ofj )i;:ka7 p:f s $m_{1}$ 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 gravitatioi jmu1n p8pvofoi wks0dd4ux83.:: *n,dy y o2n.

  Compared to its massga5xc )mp2t n7/ j0ccv on the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what0*v6 qc09frs .kbdtjf it is on Earth. An object of mas 6fbf0d9 *k.0trqvcsjs
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surfacmlo 9y,j nr) ioan r:tn80z3f1v0 5ksbe, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyh m uzflu8e7x) myt tt3:3b;i.ond the pull of Earth's 8:h3met.;3t7tulzm ix bu y)fgravity?

  Suppose a satellite were orbiting the Earth just above the surface. v a;)hzfm87vtcwx; .jWhat is its centripetal accele8 7)cm ; vwxtzaj;.hfvration?

  A hypothetical planet has a mass of half that of the Earth and a ra y ;a5qt4 (m(tyn n05hutvv.acdzy5g ;dius of twice that of the Earth. What is the acceleration due to gravity on thd4v0(htaamtq;nn5 (; tygz uy 55.cy ve 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 Earth. There qnvq zn56j3mvj,t*nzg-48 radius of the Moon is one-fourth that of the Earthvjv 5 -q q,tn6ez*z3j4n 8mgrn. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B h4eflw(w oba8w- po 8 iffx(7)yas twice the radius of planet A. If planet A has mass m,e8 (7y (f8wwiawo b)flfox -4p what is the mass of planet B?

  Two planets have the same surface gravity, but playv giu48vj198uzt0; ir cl 5fsnet B has twice the mass of planet A. ct 88v4r5uivujf 0y 1z;s9 igl If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in au vgz,0s8xp(c circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellit8u gx, vp(szc0e's orbital velocity?

  Satellite A has twice the mass of satel;1yd-i-: en5z ikd2;cvb z dw3y8demulite B, and rotates in the same orbit. Compare the two sab2u de;ny : d3kdi-8; dvicme-z5z1w ytellite's speeds.

  A person is standing on a scale in an elevator acceleratij)f q36mqj75 kma.j) nrp9gnh ng downward. Compare the reading on the scale to thekq jmn)a9nqj.hf5 )prjg37 6m person's true weight.

  Who was the first pe/:1;j z;rf xodxnq+ifq q 7f ,0gge0asrson to realize that the planets move in elliptical paths around the z;q:/ n dff1 oeq7s00gqfaxg ,rx;i+jSun?

  The speed of Halley's qz /1lh:s *)m2t iargrComet, while traveling in its elliptical orbit around the Sulqrrms ghza 21/* :i)tn,

  Let the average orbital radius of a planet be R. Let the orbital period beqi +phxo0m/q6 T. What quantity is constant for all planets o60 /+iphqo xqmrbiting the Sun?

  A planet is discovered to orbit ard-agj3z1; tk::gihdr :qli/ q ound a star in the 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 perio;qra zihg3: tldji/: 1-k:q dgd 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 a: ;uj2n-f he0cb8yvl8pzd-b cs one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What b 8cehf2bpzln-0du; jy:v8c-is the asteroid's average distance from the Sun?

State Kepler's laws.5 qd )+- hck6vfi28oykjy7mca

  List the four fundamental fudy /+ ed,qzqly1ea6n) 3y0, kxxfjk1orces in nature.

  An object moves with a constant speed of 30 m/s on a circular tracg9lk xuknsro: n 0zy 1r6p;/s9k of radius 150 m. What is the acceleration of uz k9 nlp1s0;kgxs 6r/yron9: the object?

  The maximum speed around a level curve is 30.0 km/h. o9wv6o a. q)zh What is the maximum speed around a curve with twice the radius? (Assu q9.w6hazovo)me all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the k 97oq lm8ljy0syshfl-13o2z perimeter of a bicycle wh0 1zjllymolhkf92-3 s s7 qoy8eel of diameter 70 cm when the 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 r ,h6bqti4i1caxis. What is the centripeta41hi ,i6 qcbtrl acceleration?

  How many revolutions per minute must gv4zlj d*(c;sa circular, rotating space station of radius 1000 m rotate to produce an artifici c(;zgj4*v sldal gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes aroundh6(h r k,;2c *vykuiym5j8zgh a 13.7 m radius turn at 96.5 km/h. What is the centripetal forhzcmi,;hkj g2yu8*r(hk 65v yce on the motorcycle?

  A 0.50-kg mass is attached to thjf4ed+ 4fujrj5z9 g s-e end of a 1.0-m string. The system is whirled in a horizontal circj9-rz gf5 ue +fsj4jd4ular 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 attag/8x6zll8beef9yz . ;*g alx wched to a 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's speed fa.eg / yz8zx b6;lew*98xlglat this point is given by

  A stone, of mass m, is attached to a strong string and whirled in a jraz u2z 06*acu3 h3de -w:cocvertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The stone's speed ad3j2a zoc 6w30 -:ez*ucrhcuat this point is given by

  A jet plane flying 600 m/s experiences an 5hbl9a;tb wd. acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in whwl9.ba; b hdt5ich the plane is flying?

  A pilot makes an outside vertical loop (in which the center 26 rt66cgzgbbof 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. bb trgz662c6 gHow fast is he going?

  The maximum force a pilot can stand is about seven times his weighx4 r+ e +hfyi *4mhnukric7e),t. What is the minimum radius of curvature that a jet )u7h, rir+ieke +mc4x* fn h4yplane'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 horizon-/v p+e aznh/ds0amc(tal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient s a/(nc0+vd/ e -mzahpof friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radi( idpm4 s(iv-aus 50 m with a speed of 20 m/s. The centripetal force providemiv( ips(d4 -ad by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radiu5 lm tt-rp jd:9o: u+psqe-y7lt/ty a8s 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires aa:tlt 85 :tyj+p to/dsqlp-r-uym97 end the road for the car to make the turn?

  A car is moving with a constant speed v around a levelckg:m3s c: (el curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius (ce:m3 lksg:c of the curve if the car is to stay on the road?

  What minimum banking xqjg(1zpr i26ee :-qgangle is required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ijzi2p1g(eq6 :qg rx-e gnore friction.)

  A horizontal curve oneyf1(tj6w fxkm tqv c x26w8h .z+5 -k+7qlsdk a 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 m, ban1ps/ l0gwp 691c8l 5ezlqvhuo ked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m in(m;cu b) f(c,z1xao ss 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 revolving uniformly s8x3 j (2 ealn3:ql1ab :hmglkin a horizontal circle o j m(3blell13k:2xnha8sa:gq 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 accelerate*l9 j5d*piv3rz* fpigs at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (piiz93d j*v5 glp*rf*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 consbnfuog:5y +c 1ists 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 )(xhi-efnm.f l 0x n3r70-kg person standing on the Earth, due to the ).- n0r(ihfmxnxf3l eMoon? 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 betwx61j34 yk2pkxawc*4vwhk 8 tbeen two masses is F. If the masses are moved to half of their initial distance, what is the gravitational 36cw hw jxxbpak4 *yk214 kt8vattractive force?

  For a spacecraft going from the Earth toward /xkm-+hhn ru1)jgvz2yc k2., vqlmx. the Sun, at what distance from the Earth will the gravitational forces due 2/.rzx-h1c2+vh k u jmkx.l qmgv,yn)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 ,fa pve iwj22,$7.4 \times 10^{22} \; kg$ 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-walhog.c(avrork jvi-v;,4s9b:k" at a distance above the Earth equal to the radius of th-(vj:9i ,k4 hascb;rovgr. voe Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what dist/jc8*-w bl0qi qt uf56jynl6c(uno g: ance above the Earth's surface will the acceleratiogo u ci:5yqqw6lln b6/c*u8jf0n-tj(n of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance abo 88uxt*n52 kmev rznc;ve its surface equal to 3 times the radius of Mars. The acceleration of gravity of tecnxuzknv r; mt88*52 he satellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the accelerab(-tvd.mvq rid16ge5 tion of gravity isqrv6bt mv-id5eg. 1 d( $32 \; m/s^2$. 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 radius r. Ifbqw- q;+tfzk qjb6/ p, the object is raised to a height of b,kjqf6- +p/;btq zwq3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes frof 2d jl:5zbfwd0nv3i0m sea level to an altitude of 5000 m? (The 3dfz 2 bj0v0dwn5:if lmean radius 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 the a4 +zs6rrv m1 *zy(ow4ybv-n2ffewv2 Earth's surface. What is the sat1b y4*zy-vzfmw4r n 2rvo6+vsa2ew f(ellite's weight?

  A spherically symmetric planet has four times tuvvk)59fkc 6nx ( dm6fhe Earth's mass and twice its radius. If a jar odk(mfxu n6) fc v65v9kf 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, and Sun all lie on the same line, w 4a4,stownx ib+7tl (oith the Earth between the Moon and the Sun. The Moon has a mass oi o4 wa+sx(7bn ,4tltof $7.36 \times 10^{22} \; kg$; 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 transporm38yrzz h2di kt:jkeoe.w+5be80oz0ted 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 the Earth (i.e.vlon f.l ;bs68, it just skims the surface of the Earth). What is the spee; l6b.f no8svld of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a lowuvwsyz qmh8e;1s/ t.; circular orbit about the Earth (i.e., it just skims the surface of the Earth). How ls;e w 1 ztsv8q.mh/y;uong does it take to make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in cir2te3*tqr6p j/vx9) y oq,1 j7xwa osuccular orbit 230 km above the surface of the Earth. It is observed to have a pet)wx,7*v joa6x s2e1 qj9 u 3pqoyrt/criod 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 an orbital:n tkz i7nli;6)*tht j 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 oa8t( pqg4spyck4 +pg7rbits 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 orbit) eiixef3 0*bfs. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takb i)fx03ifee* es 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is xt/,x8h- gxtx$7.78 \times 10^{11} \; m$ 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 o6*)x2w gof7w p;cjskq nce. What is the average distance from Jupiter 2fq6 *jxc owk)wps;g7to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)