Is it possible for an object movie19.k p,s/susaia5*z fi y0kung with a constant speed to accelerate? Explain/e. a1as5spz y,ufisk9i uk0*.

  Consider a particle moving with constant sp cup(pd0 : dbyr5k9kaxo e)a4-uocn*,eed such that its acceleration of constant magnitude is always perpendicular to its velocityyc(4u0pba)9uocnek* o d-:a5xkpd , r .

  An object moves in a circular path at a constant speed. Compare the directionmqb:ht /g9 1 tggdu()jh2;rny of the object's vel2qgut g;/y m(hr)g jhd 9bn1t:ocity and acceleration vectors.

  When an object experiences uniform circular motion, the dir d, pxzx4bob 9v78ot(2psy d6i*p ysh5ection of the accele v75,xpt69dbso4*h ozpysx8p id2( byration is

  Consider a particle moving with co3 t 6g-xnwq2gnnstant speed such that its acceleration of constant magnitude is always perp 2gnqtx6-3ngwendicular to its velocity.

  What type of acceleration does an object moving with constant speed in a ciryk 9r z:ni)u00qk6.hw- mr2 us/qzvlicular path experien2) miuw-v zz/r90iqks:r l6h .nuqy0kce?

  What force is needed to make an object+xuv inr x7(-n/dgpsty +*q7p move in a circle?

  When an object experiences uniform circular motion, the direction of the net fv k2jkk aoan bd3(4+y(cv3o8yorkvak8 33nc4b(+(yvaojdy 2ko ce is

  A roller coaster car is on a track that forms 8o6)tjqr e/mr 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 the minimum value for its cent)6rom /8 jrtqeripetal acceleration at this point?

  A roller coaster car (massrw xibw1ycoyt2++98 c = M) is on a track that forms a circular loop (radius = r) in the vertical plane. If the car i9bx ycy+w iw28+ or1cts 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 vertvf*2hf) (ni npqbz u,2ical dive then follows a semi-circular arc until it is going straight up. Just as the planhf22)*ibpq ,fun(n zve 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 curve of radi*dhs yo l 0)s)kf-x2ulb,2o mkus $r$ 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 .mw jtv;ml6-c 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 thel; cj-wmt.v m6 second time, compared to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it gikd7k. f t1ri60p88 ncmkx -ouoes around a curve of radius 2r at speed 2v. What is the centripetal force.kkkdn8 cupi7 r6f-ot8 1m0xi 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 speed v. If the rom vdq 0oj0s 9 +mvpuvf+ob 7a9*.o,hnsad is frictionless 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 magnit n+ 0p*q0 hbv,f svm7adsjmu.v9+9oooude to

  Two horizontal curves on a bobsled run are banked at the saj)/;;zol)la1 bn:ea* bkmy 5 yqu.myxme angle, but one has twice the radius of the other. The safe speed (no friction needed tma/ ;nj: );.)alykzelq* 1 x oyub5bymo 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 track is yo-sw/ (pk4c:z1xbhua inn 6 4not constant, but increases 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 :x(pa6n/n owsi-4 hk41zb ucy do they do this?

  Is it possible for an object moving around a circul.*jn/rj2f hsrcz6w. k4ueqe rja,1 l5ar path to have both centripetal and tangential accz/n u sr4w 1hj.j2f*5rea kcq6e.lr,jeleration?

  The gravitational force betwef+7wccec:z *zfy) u3k en two objects is proportional to

  The gravitational force between two objects is inversely proportionalxsytki+7, 3zr3p/7kn+9w asfg fl7 tl to

  Two objects attract each otahj 9q,:czs(5lr/nmoolwo)aa - (r+ ther gravitationally. If the distance between their centers is cut in half:l+5h c,o o)t(ra/- (9jmzla rswnaoq, the gravitational force

  Two objects, with mas0, oq ;xa,4t bewyvvy8ses $m_{1}$ 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 masses e4.beyfv nf )*;wm+oh/q0,w uf/t.g1zn fyti $m_{1}$ 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 grav5e inffo(r1xf-aq18opw,q4): w z qccitation.

  Compared to its mass on uz4lw50va-hp4riw * a:d6d9jv4d v jsthe Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what i df:1ecs:rchjo57 a: mt is on Earth. An object of mass j7mc:d crfeo1:ha 5:s
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket's w+q1k(r(z4 k4y1 ypknlf bsl6l eight

  A spaceship is traveling to the Mojobd xl+k 4dx c*i,yr79h )(pfon. At what point is it beyond the pull of Earth'l) b+* xdjh(y4kxpi9ofd7 ,rcs gravity?

  Suppose a satellite were orbiting the Earth just above the surface. xy)se dr c(0gvu23-mvWhat is its cen2esuxvmg0)(v 3dy r c-tripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius of a q)yw+ t0mkt4gd c5;ltwice that of the Earth. What is the acceleration due to gravity on thetwt4gmqc +k ; dayl05) planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth wh5l(abe.y b qj (b0xh,hat it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared.x5lbae y0 ((hbj ,bhq to the Earth's?

  Two planets have the same surface gravity, but planet(dshe ;xcbz 29 B has twice the radius of planet A. If planet A has mass m, what is th(ezbx9 h ds;c2e mass of planet B?

  Two planets have the same surface gravity, but planet B has td fcx +g)fb7y 2kdp-r2wice the mass of planet A. If planet A has radius r, what is the radius bfpx ygd22f7+ k)drc- of planet B?

  Consider a small satellite moving in a cir7xub,d 3yz4tqcular orbit (radius r) about a spherical planet (mass M). Which3zqutd, y b4x7 expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orseq25 m7mbo72epqo f1s3dr(+cq (gmlbit. Comfms32p(d gom+7o25emr 17sbe( qqlq cpare the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Compare z/4vc5 n*kubld: e j*6l j 9yn(ddl6xothe reading on the scale to the person's true wn*c9dll4 jyn/zbvdu6o6d*(jle x k5:eight.

  Who was the first person to realize that the planets mo8orkxnvwhf/ g i.*5iw/n8gvctn 879 xve in elliptical paths arnf8. i// gt8w975v hkwv x8r*nongxciound the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit arouv0y24cjc dzf oy83qv9 nd the Sunj 84ovyz0dcf2c v3qy9,

  Let the average orbital radius of a planet be R. Let the mwifip ic/azo-o(0q ;4-ady 4orbital period be T. What quantity is constant d4qpz0 oy4ci(oiawm/i;- a- ffor all planets orbiting the Sun?

  A planet is discovered to orbit aroy zlvz11;c ax,p c.yd3und a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 tzz x pva1.y,1d;3cyclimes 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 "astr3vx fk -);y x o4zmg6n6)kdiglonomical unit" (AU). An asteroid orbits the Sun in on3-)gvoi6 l6z) m;kg xkn4fxdye-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.ynl616)5(kmvbo) rxfvdo5nvof5ya )

  List the four fundamental jjbk**u3wj;cu+aepw2l g+ n, forces in nature.

  An object moves with a constant speed o1yproj )h(6 ajf 30 m/s on a circular track of radius 150 m. What is the acceleration of the obje(hyaj or jp61)ct?

  The maximum speed around a level curve is 30.0 km/h. What is the qlhxfe qneo i:qo, ;2: 1l7hl6b,vu1 lmaximum speed around a curve with twice the radius? o6qbhnxq2 hlf :7l ;, :,iqoe1elluv1 (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point5iyk o)xr6bf: on the perimeter of a bicycle wheel of diameter 70 cm whe)f ir bxk:56yon the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.208cn h ,/wl,wjd0 m from the axis. What iw,/ dclnh,8jws the centripetal acceleration?

  How many revolutions per minute must a circular, rotating space station of ra- -fdexsmxw1fnp 99d +dius 1000 m rotate to produce an art 1 9-ffxwx9-sddmp ne+ificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius tu7h2o .0v5 .bnyac2gni:ni5a2v msdkj rn at 96.5 km/h. What is the centrandbo sy25:ca 5vjki.2.vnhnm2i7 0 gipetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. Tks4f- s9a 8ob1 gpv zu9x8ch hq5q5ld,he system is whirled i vhcs849daxp 5qu9z bl-f8kg5oshq 1,n 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 string is not to break?

  A stone, of mass m, is /pggu do,u;z +f).qwcattached 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 sto dqu/ +fwuo,;cpz.g )gne's weight. The stone's speed at this point is given by

  A stone, of mass m, isq u61nu6 (sdj;/tb:d2b2w s0mhxqhqb attached to a strong string and whirled in a vertical circle od( ; tq0jnm: wu2d2qssbbu6/ xbh6h1qf 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 is given by

  A jet plane flying 600 m/koksj;j:jsda/ x4a*m y* w(4 kdf-j79g u(wwh s experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which yj :(;ks- *jh*dadj 4/ jmkow94xfgka(7wsuw the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop)b wn0xk bh fa sct*97e6)wlj. is beneath him) of radius 3200 m. At the top of s*.a w)ncb whe fl09 7jx6tbk)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 is aboutd1jhf-,9 gja0(uwjzt + crjc* seven times his weight. What is the minimum radius of curvature that a u9jd(ah1c+j0r -w gj zct ,*jfjet plane'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 horizevkr6pvi8( t-iv0 ; gdontal 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 v0v(;t-vp d i6i8 grkefriction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 5: n nxes xb+b0wis,;/4 mkr:ibj(rrr8p.w 7no0 m with a speed of 20 m/s. The centripetal force provided by fri7: bkr;mp: 8rne .x/0 xbw brj(onwirn4s +s,iction 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 gixy-;9v3nd+1htq bj,x fx8f a speed of 14 m/s. What must be the minimum coefficxq+1;hfgi93f-x 8bjxn ydvt, ient 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 l(86 0lwm,e tnj6a kk4;lo9aw:amoebyz 3/ sipevel curve. The coefficient of friction between the tires and 6a:ekpt ;z,0 8ewwonm/am kb 4ia3oly96 (sljthe road is 0.40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is rcugw;qnq v t b5637u+lequired for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictiovw cqn+tg375l ;qub6 un.)

  A horizontal curve on a bob*5sr :0n o+pke1y ltdosled 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, banked atlnugr-f:fw.yq (s f61 an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b 5f cfyztn6:.xc sm1izll6( c5anked 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 in a horizo. unlh5 9sg4wv myog13ntal circle ofsm43yh1.ngv g w5uo9 l 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 accelerates at a uniform rat w/qjm4k: rr(re to a spej rqwm4:kr(r/ ed 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 bco-k0yr5l ,jof 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 70-kg person standing on the Earth; 25t9h7jsycku ;p clbe/gr1/-mc sb h, due to the Moon? The mass of the Mog-clsy2/m h5sb 1ccte ;u/rb;hk p7j9on 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. If the:on sgzeh43zxbliw33 h40 yz* masses are moved to half of their initial distance, what is the gravitational attractb3eizn 4lgxh:y4z oz3 0 s*w3hive force?

  For a spacecraft going from the Earth toward the Sun, at what distareza, 4m 3uj zujng+d-) -do.xnce from the Earth will the gravitational forces due to the Sun and the4jz . -ez)-gjdomd+ ra3,xunu 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 Mooner*bajgn .yx5 v7z,q :cq* f;t is $7.4 \times 10^{22} \; kg$ 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 disuel6idc sj6/6tance above the Earth equal to the radius of the Earth. What iu i6c/ el6s6jds her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's sxs 1,7jm 8ivluurface will the acceli1ux j v,78msleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars /qcj ; 2 )nmvcew9 cseeiz8,d4at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface ofsjz8, n qv/cee2 m9c)eci w;d4 Mars, is

  At a distance of 14000 km from some planet's center, the af:ws aea5xjafg 29a r- ,iy.4u26rahr cceleration of gravity is i4a rguarsrf9-yxf2aa 5,: h2j6ea w. $32 \; m/s^2$. 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 Ea,d2mz z9 fzhz 3kpnz1/ :q.ijurth has radius r. If the object is raised to a height of 3r above the Earth's surfacenpz9 3,ifzmqzz du1k:2zjh ./, what is its weight?

  By how many newtons does the weight of a 100-kg (pbxnec13 n0;z,oa vz person change when he goes from sea 3;enx1pbzn0(cvoa,z level to an altitude 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 above thy rtc 47 ht86mn4jm;egxkt;)l7hc o7ae Earth's surface. What is the h4;t7reg7 c y;7ok8 6tnlmat) xjhc4msatellite's weight?

  A spherically symmetric planet has t p2teixdv19tlc. k u bjbq61) lq*l90four times the Earth's mass and twice its radius. If a j19jq9 0p cxtedi 1lb6*2t) ktlqvblu .ar of 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,mz:b/ u ;lwzyz/1 huw1 and Sun all lie on the same line, with the Em;/lyz 1 w/ zubuw1:hzarth between 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 the Moon. .sp mpp,+pj7 t
(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 vwmu0 xi: w; )kswcn;clq:5o (orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed of the satellite? (The mean radius of s5u:xww0;(il;nc )co wqmv: kthe Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., t5or e2m. mgwo owtp6vgb/+46it just skims the surface of the Earth). How long does it take to mg2vt6 opwmg.wr5o/6tb + meo4 ake one revolution around the Earth? (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. It p+(t d *6mjvstis observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of th p6(s+ tv*tjdme Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbidn+tbtn 3, g8ztal 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 z s5wmy 49zkpjq5wi4; 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. Moog1:t)c gm xg*ux8 mv3zn A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete v1gg*cxu)m3z8g x :tmone orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is 7(/i:mfv:ktkvv)fp d $7.78 \times 10^{11} \; m$ 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 (/,ztkgscy, m 12 years to orbit the Sun once. What is the average distance from Jupiter to the S,,m(ks gy c/ztun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)