Is it possible for an object moving with a constant speed to 8cmfd5 ce-ct,bskm6j fg(1 (jaccelerate? Explainf bcf kj,mme1st (5g- 86ccj(d.

  Consider a particle movio 6le 2k5z(yeong with constant speed such that its acceleration of constant magnitude is always perpen5ly2ok oee 6(zdicular to its velocity.

  An object moves in a circular path at a constant spoziwkz2 0vkn 1d-s 5h7eed. Compare the direction of the object's venikz-swz270hd51 ovk locity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the a xwikzniw 9i7ak;4,e mof9szo8 ,-e -mcceleration ;9nii9im-kk,oawe 7,e zwmfzx o - 84sis

  Consider a particle moving with constant speed such that its acceleration of conm6z 6 blbn)/by)fvx; xstant magnitude ib6bbmxzl) v;/) n f6xys always perpendicular to its velocity.

  What type of acceleration does an ) (fb*i(na(t oes.worobject moving with constant speed in a circular path eabsw*roen () (( fo.itxperience?

  What force is needed to m z*o,t+vek y6xake an object move in a circle?

  When an object experiences uniform circular mojl,nw c:2e ux epk-j97tion, the direction of the net force in euw-9x:7pl ,k jj2ecs

  A roller coaster car is on r2k7:m*8rxip p83ii rcff mz k:2b o,o dqxs.)a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top ofix23x :ciik kpf,oq:)8z*os rr.m bmrp87df2 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 c qk8; m.:7io xlpwss2db 9,zuv 9qk,pcircular loop (radius = r) in the vertical plane. If the car d qk2l;8p 9sbm.v pi : k,,9szwc7xoquis 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 vertical dive then follows a semi-circular 6 1wqx:8tgran, mrr73l uj.a sarc until it is going straight up. Just as the plane isjt1mrq.ugx6 a7 rlr,wn83a:s 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 of radius+buik)/hdc c dh9 kz29 $r$ 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 constant speed) +/*pw4dxmx jjmjnscw7au 0 1s.4due 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, comp+jw 4n1xaw*mdj0 se 7.s/px duj)ucm4ared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it goes l hl (bm4f+s:karound a curve of radius 2r at speed 2v. What is the centripetal force on the car as it gohml:kfl+b 4 s(es around the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r wip g4-u5c ni(gwth speed v. If the road is frictionlesp(w4i5g- ugcns 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 equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, bu+ jbd4 dvsf.q9t one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the+ vqd9.4b dfjs 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 4g(*feo;y mjw,(qsg;ggn gq ( is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming o;,e w qng(4o(gj;gf (*gqgymsut of the turn. Why do they do this?

  Is it possible for an object moving around a circu(1 y); vydeukta8br092t,rp 1ikj toolar path to have both centripetal and tangential acceleratio1 kt9o8r(, j k ;t0yyi2)pvtb1d aueron?

  The gravitational force between two objlh5l7-d :pgwt 9 pkb3mects is proportional to

  The gravitational force between two objects is inversely proptu/w, n b 5gn29mn(c nch.pj+portional to

  Two objects attract each other gravitationa f/:kbggf5 ef,lly. If the distance between their centers ,e k/5b f:gffgis cut in half, the gravitational force

  Two objects, with massm jff. 4 a3brxq6t8s1oes $m_{1}$ 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 malxl8h4 esd4q lzz-zgtw,c+. : 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 )r-b 5xkrlkmcg-8*ed universal gravitation.

  Compared to its mass on the Earth, rvygy+9tdf3z6o(34n qf( awr the mass of an object on the Moon is

  The acceleration of gravity on the Moon is o2p(0.dm kjab cb0.:s7 xy7k etqccvo. ne-sixth what it is on Earth. An object of mak.cbpb .dcm7c(k tja70q s.y e0vx :o2ss
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from t,1 d89fw4kir cq e-xi4qj(ko vhe Earth's surface, the rocket's weight

  A spaceship is travelirkpxm0mnc/3b7w-u n2 s 5kr:ung to the Moon. At what point is it beyond the pull of Eapn2 ku/xn35rc s 0u :mwmk-7brrth's gravity?

  Suppose a satellite wer1 v*3jfq)m )kn3 c9hzpnpwt:ie orbiting the Earth just above the surface. What is its centripetal accel3ih) )3 kzwcpm *9q :t1jnvfpneration?

  A hypothetical planet hasu1baajom6td v609* a n a mass of half that of the Earth and a radius of twice that of the Earth. W06tb*jv9n udamo6a1a hat 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 is o9)df88uen z7+wxial yne-sixth what it is on Earth. The radius of the Moon is one-f9wd88a zie7 )ulfn+xyourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity,o g)0 y+( gezbveo)tf q76t-kq but planet B has twice the radius of planet A. If plgoof7gv6q0eqt e(t+ yk) b-z)anet A has mass m, what is the mass of planet B?

  Two planets have the slnhn ,w6-uyr1pvf4 4; j8dvh kame surface gravity, but planet B has twice the mass of planet A. If planet A has radiuwkh 1-l fnr46 yj;p,4dnu vvh8s r, what is the radius of planet B?

  Consider a small satellite moving inxmx.fnfbie0/:s0 l/ a9dgl +w a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbita9gb fna/:f xw xd+m 0li0es/.ll velocity?

  Satellite A has twice the mass of satellite B, and(ufkijs5alu73f:y, w rotates in the same orbit. Compare the two satellite's speedku (a37s wu:lffi,j5y s.

  A person is standing 4e019 iq;e z .cy8yvr u,rckayon a scale in an elevator accelerating downward. Compare the reading on the scev,zar 0ey 4ircy9;8c.kq1 yuale to the person's true weight.

  Who was the first person to realize that the planets move in el jh;dfhwwvhv4ihq .05f1m 9b fhjt4(2liptical paths aroh jf ;dhwt hh5.j 4fvmhf2wq9 v04b(1iund the Sun?

  The speed of Halley's Comet, while traveling in its;nhj+;t 2 5kiu 9ps;xmwpxx 8c elliptical orbit around the S+h mpp2;9j5x; ; ncxsi 8wktuxun,

  Let the average orbital radius of a planet be R. Let the orbital period be T. 9 q4;au i07xzryv(,lfnsu + zdps/ju: What quantity is constant fl(/d jxu9;4sfzu,qya0 s + :uzn ivrp7or all planets orbiting the Sun?

  A planet is discovered to orbit around af6 5wcaj(ikia*9 ,ps)tjn,a eq6gp6i star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass o gp)n6 es65a,c9ijwkqa6 (a* ptfiij,f 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 :*:eu 5cdv xfuSun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun inu* e df5xc::uv one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.y7 4i.fl0z:kr/a7 ysvvc / sjz

  List the four fundamentalhg+1jz kx9n y( 6t3s(f g-fu s3nxyub/ forces in nature.

  An object moves with a consta vh 5un4) 44tvdb(g;j5jyi dqgnt speed of 30 m/s on a circular track of radius 150 m. What is the acceleration 4qyn)h5 dj( g4 uvdvi;5 b4tjgof the object?

  The maximum speed around a level curve is 30.0 km/h. What is the max sbb 5g-4//:quetug wpimum speed arou qeuutb/b sp-g:gw /45nd a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimeter of6fq8i*,k: zahcd r5vi a bicycle wheel of diameter 70 cm when the bike vk*5a:chqiif8r, z d6 is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.28m0 ywhw8fqs w 4h/tbsw8(c0b2(dmrj00 m from the axis. What is the centripetal acceleration?0rds(8wbwhm8hfm8 w/ytqc0bws 2( j4

  How many revolutions per minute mustk uhqis .0) xnvoj6z+5 a circular, rotating space station of radius 1000 m rotate to produce an artificial gravity oi0s) .kx+vquh65o j znf $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 76l pf pfeeam8(ni24akg. It goes around a 13.7 m radius turn at 96.5 km/h. Whfn pa(ee4ilm p82a76f at is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1. epz6c( e7w2sojk2 sxrlhej6).i, z9;6dusch 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 ifhoe96dpr7(;c s6hzuse j wij2) ck.lxs,2 ez6 the string is not to break?

  A stone, of mass m, is (vzdl ;o di;g:g/zfo82oz3 ,af nblr-attached 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 ;(ab gf,rzz o/zvo oldfi:ln28 g-;3d. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirwajmz2*)zw r3m8 ik-mled in a vertical circle of radius r. At the exact bottom of the pa8-32 r*ajmz) zkwimmwth 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 experiences a. 77auy pvs.etn acceleration of 4g when pulling out of t7.e u pyts7.avhe dive. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in whinuhv4, er bf.d4n.q c7ch the center of the loop is beneath him) of radius 3200 m. At the top of his lood7qnu , c.verhbn4.f4 p 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 is about sev*gc+) o civ sh5ixv5*jen 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 sp +ic v*hcxoi55vj )*sgeed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontp 7j+m06sje9ulh(jax bo l+)lal curve with the tires on the vjxaebl (jlpsu9+0+ 6)7moj lherge 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. n wi.za.;e8;*n3kzvice zh:d The centri;w3ziken8ehza .*zc n: ;vdi.petal 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 o2 tdsyw* /s :6p5mjujyf radius 50 m at a speed of 14 m/s. What must be the minimjydms2w6u5 : s/jp *tyum 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 aruzk+ 7 j*9fe3f nizkk/ound a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radiu+zk* 3jzn /7ek9fufiks of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Oldcix.dk+a il:qw;v mwl;5 y/3ympic bobsled to negotiate a 100-m radius turn at 35 m/s without sixv :ddmyal; 3qk+./5ww ;ilckidding? (Ignore friction.)

  A horizontal curve on a bobsled run is v wcmv8pz;;+nqwft:m,j9 )lx:xb q,kbanked 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, banked at 2iaat f1dmme 4 zn8a;;gb) p1man angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at v-ek v.dm-oo, $45^{\circ}$. 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 in adjtinf jj /ovs2 69(d bh/jz/-t(/h ;/qi hxjm horizontal circle of radius 0.bv-ih mx/hj / njj tjzd( /92t(;ihjos6f//dq500
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 a8jf r*,gw+ hqaccelerates at a uniform rate to a speed of 45 m/s in 158 *w afq+j,hrg 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 con4vg cfblz ,,,ksists 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 .b1dyw jbi42qgf 9.u:,saqf e70-kg person standing on the Earth, due to the Moon? The mass of the Moon f.ef b9,qq igya 1dj :4u2.bswis $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masses is F. If the mas4: wez 1k5(dari (pkszses are moved to half of their initial distance, what is the4(z5 (zis akr:pde1 wk gravitational attractive force?

  For a spacecraft going from the Ea(w(ekxk1 0crx rth toward the Sun, at what distance from the Earth will the gravitational xkwr0e(kcx(1 forces 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 :le i mapu5t7(e1hijkt:(hj: ,xt,nd$7.4 \times 10^{22} \; kg$ 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 d3c4bh1)s 3oz mxc ,jlkistance above the Earth equal to the radius of the Earth. What is her acceleration due zklbm) 1ccxj3o 34s,h to gravity?

  The radius of the Earth is R. At what distance above the Earth's sum) b8/; )bpmkjhk/tcfrface will the acceleration ot8hcbkfm);jb/ p mk/)f gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its sumzoii8j:o86 2gvclpsz w9l 1r iy82 3rrface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the slli 8srzivo1m8jciwr: 9628zg p y2o3urface of Mars, is

  At a distance of 14000 km from some plane g/wygd(u eu9,t's center, the acceleration of gravity is,(wgy9d ug u/e $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 Ncj szn9zkjt+c,3rsr v l14r1 ( 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 surface, what is its wei crzv3lt s+z4(, rk1n9jj1 rcsght?

  By how many newtons does the weight of a 100-kg person changy..ub c*y,+ddu -ayw we when he goes from sea level to an a *wc-u.da,.wy+ ydbuyltitude of 5000 m? (The mean 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 aboo;3y+xur my) 15f xww 5sip;bxukrq/ 0ve the Earth's surface. What ikf3u r) r1 y5o xi;sxwyb/ +wmxp5q0u;s the satellite's weight?

  A spherically symmetric planet has four times tf -p;3;kvopi)8jr4 ot pw.wa*zf7v/w)ur cidhe Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would irv )u;3 /;. tipcv-afkop8w4*dz wj 7ir )pfowt weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sw0d6tvus/ h- iun all lie on the same line, with the Earth between the Moon and the Sun. The Moon hashswi06 dt /vu- 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+y -0(avd-5 thtba aob)g0f7ckn x1n phe 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.fmkr +ioe(+9 mr1xv*lg/ y jwm2r +zgdg1l))le., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of the E +yrz+md+klgl i)1/e xlm)wvg (j1o2 rg 9m*rfarth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just skims tctqyv y(p ve3 *0bbn;2he surface of the Earth). How long does it take to make one revolution around the Earth? vpb y;0tnbqcy2 (ve*3 (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earth.co:xi x3ah-lqi 8fx+7x d2sw( It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the Earth8 cx3+:qw-7hxioa(lf dxs ix2 is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter rn91(5tj-ajalwoi h0 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 5.w z tp:aeugv-5v;w fwith 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 orbib+ o bizr.uzur-xldw3 4 ez,o+z 2o;7ets. 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 com 3d4rooo2;bz + l,7ze+. uzwz x-uibreplete an orbit?

  The planet Jupiter is ouh;o/ uisfjmp)b04 5 $7.78 \times 10^{11} \; m$ 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 year ovsd;/xb ; m1)pbdo,ps to orbit the Sun once. What is the average distance from Jupiter to the Sun? (p)b,d ; o;pdv oxmb/1sThe distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)