Is it possible for an object moviqt :6;v7e4gxk,j. .ko nhrd/d knppx7ng with a constant speed to accelerate? Explai kx6.g4q7p 7dnov:.dtkk; /xprj,he nn.

  Consider a particle moving with constant speed *y1fno3qi0px14n*sf4 kt loi3ghj e8such that its acceleration of constant magnitude is always per4o1ejhp81tk xnlifi*q43sf30 ynog * pendicular to its velocity.

  An object moves in a circular path at a consc.3rvt h pj):ftant speed. Compare the direction of the object's velocity and accvhct.)rj 3f :peleration vectors.

  When an object experiences uniform cl 4wr eq/ (t3)hj3hwjeircular motion, the direction of the accelerat) wjjw3lh/eq er43t(h ion is

  Consider a particle moving with constant speed such that its acceleratpnff+5nck w5 *ion of constant magnitude is always f5 *wpf+ncnk5 perpendicular to its velocity.

  What type of acceleration doe0vys.6fk m (*vvp6mmcs an object moving with constant speed in a circular patvf6m sk(.*yc0v pmv6mh experience?

  What force is needed to make an o0x e3gi5 pmajh b1da9+pz;(mfbject move in a circle?

  When an object experiences uniform circular m(tcjfrdc*1 i 8otion, the direction of the net forc(iccdt8rj 1f* e is

  A roller coaster car is on a track that forms a civn 45 - p0johmrrj8b,ercular loop in the vertical plane. If the car is to just maintain4,b5r-h08 jmoevpnrj 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 foryz4yv 0bnez u)//)b wkms a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of the ))be//w4kz0yvzb nuy loop, what is the minimum value for its speed at that point?

  A pilot executes a ven98e4cm/n rvt rtical dive then follows a semi-circular arc until it is going straight up. Just as the planen4v t98mc nr/e 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 cd-iytxsa8/ 2 hurve 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 radsse m4pdr-0 2yius 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 around the curve for the second0 e-rssd2py4m time, compared to the first time?

  A car goes around a curve of radius r at a constant speed va7il v /qj+q;t. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car ajti+vaql /q;7s it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with speed v. kj68uw)rxe s; If the road is frictionless due to ice, the car can still negotiate the curve if t)k6j w r8xeus;he 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 one tzg gwt2m /w+4has twice the radius of the other. The safe speed (no friction needed to stay on thez/2+mgwg tw4t 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 ri s9+q9 ue/xqbobsled track is not constant, but increases upward from the horizontal. Coming around a q/+xusi r9e9qturn, 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 have both cecilnrf u:+i3g/g7-j:jtb- r jft/ ds ,ntripetal and tan:3gn-if b /s tjifrl,:jt-du7c+ j /grgential acceleration?

  The gravitational force betwiyd/3c2l f.vueen two objects is proportional to

  The gravitational force between two objects is inversely proportiofrf0v6 9x:85 ia(7kbv ory ffvnal to

  Two objects attract each ov)d/wj h7b9 k2 eq.jsjther gravitationally. If the distance between their centers isq 2 )9 e7jsdj/vbjkhw. cut in half, the gravitational force

  Two objects, with mass)wvl8krat(:rz 8(p goow 0t5res $m_{1}$ 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 ma3t/i-scq+ d6n9rcqs nsses $m_{1}$ 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 lp,awuv y t5922 3whbvb*e8fi gravitation.

  Compared to its mass on the Earth, thew 1k1fyv,h6pv mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Eartle/7 1fj 8kf kw.3sogyh. An object of masswg1sfj k8k7 ye.l o/3f
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rockeb4q5ha xln5k+ t's weight

  A spaceship is traveling to the Moon.n2 1 ghg9 rkvgtn42h9d At what point is it beyond the pull of Earth's grad r4n129h 9vn h2gkgtgvity?

  Suppose a satellite were orbiting the Ear fyecqg 7. 7sbgn/lzem y*/6+cth just above the surface. What is its e /g+fm/7g6* 7nszeby . ccylqcentripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and ag9p wj2gs+x4 c radius of twice that of the Earth. What is th ps4 2g9+cjxgwe 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 one- i+ 8u7tkm*fyysixth what it is on Earth. The radius of+7 ykt uyim8f* the Moon 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, bxn2o0gbb wi6- x3sz q(ut planet B has twice the radius of planet A. If planet A has mass m, what is szobxiqnw 6(g23-0x b the mass of planet B?

  Two planets have the same surface gravity, 5a6hyz8v7d k98rdr,wdg us se7- de3rbut planet B has twice the mass of pl6e7, r hszs vg5 73w8-ue kry9ddrda8danet A. If planet A has radius r, what is the radius of planet B?

  Consider a small satellite movingl f v89hl )9sj*1zch-fv+jgzw in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital9z vcwh 8)j fzjfv+l1*9- lsgh velocity?

  Satellite A has twice the mass9) ao vw g:xtxono do7;wr(-g3 of satellite B, and rotates in the same orbit. Compare the twog7v); owtna do(9rgo ox:-3x w satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compared tx+nn. -x38 qwtb2sc the reading on the scale to the person's true weig-sn2 xdwtb cntq3.x8+ht.

  Who was the first persoda4j-.-mv l1x nn0 ysw(fib- vn to realize that the planets move in elliptical paths around4vn-(ni0xmw f1s. -alj- v dby the Sun?

  The speed of Halley's Comet, while tray lghw7:t x)e6veling in its elliptical orbit around the Sun:t 6)lgh7yexw ,

  Let the average orbital radius of a(e5zlkyx n5)u) - qp erkj0i+c planet be R. Let the orbital period be T. What quantity is constant f-xye(5lu rkz ))n5p jc0+ qkeior all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Atbd, ibmx):** )v ojyhz5ac li;e;r :vndromeda, 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 that new plane,vv5i cab): lo; *:imezbh)r ;j*dxytt be, compared to the Earth's orbital period?

  The average distance fru /7ma3verp+sx*y oqyk bi (4d,8e 4inom the Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's averagyu43r/q x8de *ei b7 myi+vpn,(sak4oe distance from the Sun?

State Kepler's laws.kl.6s0)lmv cn

  List the four fundamental forcsh xb;/r:n/dgu,q1si.+edd g es in nature.

  An object moves with a constant m,n6v1jyz (pu/t v ue + h/-unsp+dfd-speed of 30 m/s on a circular track of radius 150 m. What is tv p/e +vd/n-t6j,uu -s+mu(pyfn hd1zhe acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. Whataj-l z1t5 j4:o1jfrkg is the maximum speed around a curve with twice the radgajjjr4-klt1 : fo 51zius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the peeg *9luo dv ma755o2utrimeter of a bicycle wheel of diameter 70 cm when the bike is moving 8.0 m7g2a u* m59eotld5uo v/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 o j88 mf4o:vdem from the axis. What is the centri8o:4 emfdojv8 petal acceleration?

  How many revolutions per minute must a3y 4/lkv99s5lk;owwr/gmry p circular, rotating space station of radius 1000 m rotate to prodl953lp yk k;9 vyrsrmo4g//wwuce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 ml723dy*r ru*/xaz ehf radius turn at 96.5 km/h. What is the centripea*yxf*h3urr d2lz/ e7 tal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0ij.par f adc w)4b46y.-m string. The system is whirled in a horizontal circular path. If the maximum tension that the strincb fjawi4pa6y4r .d .)g 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 wh u48vd(bsg7j/xlxh8e irled 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 w/74e88xsxh v(lgd j ubeight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in a vertic;0 ugqmmc i kc)adu1*1al 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 at this point m cumqd)1g0ka u 1;*icis given by

  A jet plane flying 600 m/s experiences an acceleration o+ciz0yn47gg3; u; dku p j/inff 4g when pulling out of the dive. What is the radius of curvature of the loop in which zjdp 3gyic74n;/gi kf0;u+un the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop im e):i vwifx79s beneath him) of radius 3200 m. At the top of his loop he is pushing dowewm i)i:79vxf n 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 seven times his w +zelj c18ex)ljxka/6eight. What is the minimum radius of curvature that a jet p/6)xecjz+8axl jl 1k elane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rb51m( 4 hxskxpounds an 80-m radius horizontal 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 of friction between the car's tires and each road surface14 xxb mpksh5(.)

  A car is negotiating a flat curve of radius;ku;-irw u )is 50 m with a speed of 20 m/s. The centripeuu;s ik-wi;)r tal 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 +qn o.e8x;yeegfhq. + m at a speed of 14 m/s. What must be the minimum coefficient of frictfeeo.x q +.+hy; ngq8eion between the tires and the road for the car to make the turn?

  A car is moving withuwmq / /: q8ki4k6m1xf l4q5 jcn3suyw a constant speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radiuswk36m1qjuwn4lx :uiy m5qk4 f/sc/ q8 of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic 6s+z9utjyc;n s f17cu bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore fri+69u1;c7j n fu tczsysction.)

  A horizontal curve on asht *+j4a /rro 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 ml nf4 (o1mhet+j6b3rm, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80q.9 hob 8.u)w4uw.,jwzrym d a 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 )ghai n4+ u.l7rtw.qq3ceqi5end of a string is revolving uniformly in a horizontal circle of radius 0.500 )h.7.q au+qwqlt53 ec 4ignri
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 uniform rate t unjk5 -xk(3o/oru2ls o a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical value in the su( /35lrjkuo- konx2blanks)
(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 proton of masq4oku: i)6vzh0t ah,qp9*u gcs $1.67 \times 10^{-27} \; kg$ 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 standing on the- hgj5y,qm )q cn4y*dh Earth, due to the Moon? The mass of the Moon isc*d5qghjm- q4 hyn ,y) $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between two masses is)+gnl .dgny6 8rdmpg- 8 -y d1z0jndu 1vra5gv F. If the masses are moved to half of their initial distance, what is the gravitational attractive p1 ln0 uyadnr+v 6v-1-zgdjdg.8)5ygrndgm 8 force?

  For a spacecraft going from the Earth toward the Sun, at what di7( 2 mpbsh g469,r2wi7xj talaub. popstance from the Earth will tha 76 2ml,2psp i (a4xbwh.o7jt rbpug9e gravitational 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 orb)2 r *tk ka)47hpig$7.4 \times 10^{22} \; kg$ 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 ujdh7 px iooen82pv/cx5 j;; 4a distance above the Earth equal to od4 h u8pxo/;n7i;je2 vpc5j xthe radius of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth'.vy.r:zl jwnln+1r 7u suy. aj-io:/oif1tt3 s surface will the acceleratio. w-u/1yjnnlor z.:y3ji.tvo lfu1ras: + i t7n of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times th/vh 7ec qhf )/5.7pwbmjf+fsi e radius of Mars. The acceleration of gravity of thf5 s7jqe .fp/mvc7h/ )wbi+hfe 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 acceleration of gravit 7h9i4 9adz0jzxdqavyx1 g7i3 f.yvk- y isagq7d.d9 1 zjzx9-fhyv xk7 0 43iviya $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on the su*+-ju(r q24 jluoua kgrface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, wha *2(ulq r+kujju- g4oat is its weight?

  By how many newtons does the weight of a 100-kg person change when he)3krn q/ps q1.st4wax goes from sea level to an altitude of 5000 m? (The mean radius of the xap kw).nqqst s3r4/1Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satyzo)6qm*oqy * 4/dk qbellite of mass 100 kg is at a point 3r above the Earth's surface. Wmbq oq/o*k4q y)zd 6y*hat is the satellite's weight?

  A spherically symmetric planet has fouzvrnw(m0*k+, p m-o plr times the 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 it weigh on t*k w-+nolpvmzpm(,0 rhe surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all li d8vb7 m)47rhphbjt k7be7gb3 e on the same line, with the Earth between the Moon and7he8pbv7bbtjb7 g3 r)hk d7m4 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 )) arg3 ubj+4nt intgom87:4eccxvb: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 l(prl r vlsmuenh t8;ux; td,+g6 ,y)u+ow circular orbit about the Earth (i.e., it just skims the surface of the Earth). Wd;,v ( gt) hl8suplt 6m rexu,y;++rnuhat is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit abot7emp xcr6h)5kkn ;1k dm lj1-ut the Earth (i.e., it just skims the surface of the dpk) -1ncl mx15 k6et7jk;hmrEarth). How long 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 cirv8 (dr+0s f:4glok, mtt* lbusrs+ ms/cular orbit 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 /mst4ldb* ,rg+: s u0sfkl8omt +sv(rmean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has4os3-dggya hb02 l+r v 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 the pln (ca-+ oifjd;anet 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 orb mbe/*4fxh.vztj73lo( gn fj9fz5 k3a ital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How longfo5lz7/( nbfkej3fgh*.axv 49tzm3j does it take moon B to complete an orbit?

  The planet Jupiter isd (e 05b;yysvd 5acct2 $7.78 \times 10^{11} \; m$ 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 avnxj- ov qi5al5(/k0xem 0qns)erage distance from Jupiter to the Sun? (The distance from the Earth to the Sun asx0 nivqqk -l5m x/one(j5)0 is $1.5 \times 10^{11} \; m$.)