Is it possible for an object moving with a constanqxq2 e. v:)yjqr 5xm1lt speed to accelerate? Explain.r1: x)qx emjyvq5lq2 .

  Consider a particle moving with constant speed such that its acceleration of comuxd,-lk1 zjj-b9+g onstant mag9job+ g-, xml-uzd1 jknitude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. ;pygj/ud 4w/3 hgmlg)7k x8sf Compare the direction of the obj/wmhxdglu834g;y fs gkj /7p)ect's velocity and acceleration vectors.

  When an object experiences uniform cirj-1 55b.vn ;i favdx 2nt9btmbcular motion, the direction of the acceleration isf9jbn2axv b1mn-.55tb idtv;

  Consider a particle moving with constant speed such that itrpt;0 2xy- mgos acceleration of constant magnitude is always perp-y2t gm0xp;r oendicular to its velocity.

  What type of acceleration d8 qb+:c1or;w1 tslromoes an object moving with constant speed in a circular path mq;18s twlc:oob1r r+ experience?

  What force is needed to make an object mov x u3v/z3;b4-7wlt vwt3h iaype in a circle?

  When an object experiences uniform circular motion, tid +m18iphp49nihdp, he direction of the net force ispd9+81p 4ih iih,mndp

  A roller coaster car is on a track that forms ed 2rk zc b rg;:2ru:fn++mukdyj )82ya circular loop in the vertical plane. If the car is to just maintam2r +k2urnc);d8+jy: gr:e yku2 zdb fin 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 8w2x t4anqh3 d+d0st ua track that forms a circular loop (radius = r) in the vertical plane. If the cauht dwd0nx+8qt sa432r is 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 foo/zz trdtx(y,7 0 x:zkw20rjc skwf3( llows a semi-circular arc until it is going str 7x sdj k(yw:2r0,z0/r3wcf(okxttz zaight up. Just as the plane 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 radius;nl)fpz /*u- njd 2mhs $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radius czy 6-8bctua9gt 1j8wr 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 g-cy1zb8t8t ac9jw6 u 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 ityxpe5o56 rkm + goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around y56p+5 mxok erthe second curve, compared to the first?

  A car of mass m goes around,dxk3 pd5*fozd t)3 oo 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 compo p5z x*dd3 )do3fotok,nent of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled ruvzc)3gd0e3( 0v yion t6ab,jz1 i siezbn; k40n are banked at the same angle, but one has twice the radius of the other. The saf e dy 0ibze 4ntzn;(a6g00bi,ioz 33ksvj1v)c e 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 tu(ku swpj7 r0+brn on the Olympic bobsled track is not constant, but inc 0(7r buw+jspkreases 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 moving around a ciws5 2yf vm8an:rcular path to have both centripetal and t:w 2asf8vn5myangential acceleration?

  The gravitational force between two objech syg f9jtf3d. 1.in1uts is proportional to

  The gravitational force between two objects is inversely proportionnut7 :fczw . dt.x i3x8u0 7ykmi2j3hbal to

  Two objects attract eachm9sbtot4, 6ttkhd y7n1tv,r5 other gravitationally. If the distance between their cen1t ,b h6mont9vs5 r kt,4dytt7ters is cut in half, the gravitational force

  Two objects, with massz )i5mnq3 rbh+yi zcbm:aq1+/es $m_{1}$ 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 mas8l co19g-.2d;ty+ yjpubk h rcses $m_{1}$ 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 gravidx*5vyr e*y g,-u 8mvptation.

  Compared to its mass on the Earth, the7e a)ub dzd6r/(mp-ix mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. )i v9p4zgq1 2spsj xmux)h4cw, sil+zi2l 3+p An objecs43 pc9wiquipx+m,g)p12jl)s4 si hxz2vl+ zt of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the b,h6g.vuh8hvy;go f 0Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pullnb;,5ujy y9e b of Earth's gravibj y y5;ne,9buty?

  Suppose a satellite wer mmoklzxg- 3i8r)6 1xne orbiting the Earth just above the surface. What is its centz-)1m lo8km3gn 6xr ixripetal acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radiusi3luj vx-az)t1(uy k4 jin+l. of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the accelerat(ii+ -z3kl1u)a.jv jux4 ytlnion due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixud(20gj q igv5b3fe4 mth what it is on Earth. The radius e05fudb2vg3qg4j (i m of 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 gb)x) (f )c2 ggoelj5ndrs -1 ej:n.awgravity, but planet B has twice the radius of planet A. If planet Aee)a) gw-l)foc: r5.xgsdn(1b jn 2jg has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, 72dkqd le:(tah5/zkk but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of plkde57dh2q : k(zla /tkanet B?

  Consider a small satelsb-l.(m i2phllite moving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satell.lip -bs lh2m(ite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates p b*- *283;k qol ys9tftkkdhlin the same orbit. Compare thepkl9q8y h- ldso* 3bktkt*2f ; two satellite's speeds.

  A person is standing or +zkg2dun36n n a scale in an elevator accelerating downward. Compare the reading on+r62dkzun gn3 the scale to the person's true weight.

  Who was the first person to realize that the planets move irj8f,c+ foe2nn elliptical paths around rf2nc jf ,8eo+the Sun?

  The speed of Halley's Comet, while traveling in idf:q6:m9 1x wn 0q zxekl8qv4nts elliptical orbit around the Sun,qw:q6 dx 89nl xq1 e0z4fv:mkn

  Let the average orbital radius y q8-.x b;xg5blfd) upof a planet be R. Let the orbital period be T. W.udx fb)px5g- yb ;ql8hat quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy chl c el3rti7-y qry;ia ,3l2t(ba)h:n0xb;y 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 period of revolution of that new planet be, compared to the Earth's orbital p3cqhe-,atxn20ry) l;; 7brhyt: (lyialbi3 c eriod?

  The average distance from the Earth to the Sun is defined as one "astronomicaljrglo2 ( czx03 unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asc jl( xgr03z2oteroid's average distance from the Sun?

State Kepler's laws.c:nykupf 8vkrqo7 )2ud oa848

  List the four fundamental forces inouz)x j07ik 2 r;wh6zuq7kxc ( nature.

  An object moves with a constant speed of 30 m/s onw0dpo5y cb+ix q6of4r8xn c.4 a circular track of radius 150 mxofb x cd50o44 8rqnwiyp+c. 6. What is the acceleration of the object?

  The maximum speed around a levexwoi-1f) hcgveea8 .*l curve is 30.0 km/h. What is the maximum speed around a cu-av f.)1h8oxeige w* crve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetvuqs .3+glntlxr,g6)ub -yn/al acceleration of a point on the perimeter of a bicycle wheelu -qgu+vtl ,sbr g6x.3n ny/)l of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rfhbo 6xf w+*po:ut9a0 otating at 5.00 rev/s is located 0.200 m from the axis. What is the centripetal acceleftp6+af wb*o09:h uoxration?

  How many revolutions per minute must a cir x9mg:(o k d9wlkf9zml+l,ni)cular, rotating space station of radius 1000 m rotate to producel fo:x9nmld,( gwk9)zk9 +li m an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes aronbd5f -*,/ tg0 xemz28mrjo ehund a 13.7 m radius turn at 96.5 km/h. What is the centripetal forc *08mo2ngej tbhmez5/-xr,f de on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m s2olvw8pyb-0n tl 8 0o+3db tpd70kulstring. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is thdn0usy30bd-0k bo tptwl2 p8v87lol +e maximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled ka/8zzpy(2g-pwa44f ,mi gvv 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 at th /zy,v4pp8w(2mgak4z fag -viis point is given by

  A stone, of mass m, is attachew*fa9i40g2f rssdg .cd to a strong string and whirled in a vertical 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*d0c4i. r29aw fssgfg's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of duz-+gip 5j p34g when pulling out of the dive. What is the radius of curvature ppz i35 +duj-gof the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the l+oqoy ff* cg15n+zppa7vw,n 0oop 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 pw oop z7f1aq n+0n,* vfg5+cynormal weight. How fast is he going?

  The maximum force a pilot can stand is ab 7,pc. gsacfxvw3 .5dzout seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical divz3v 5s7.cd,cxag. wfpe, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m rah+r z1i7 u:sqgdius 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 rogs7 uzqh ir+1:ad surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. )t2 uctx f-j :5u, ;dvfx*tlxcThe centripetal fot ,:tuc5l-fxdc xj*v2ux ) ;ftrce provided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve o. 4 d.h2oy6qdxfp69k7 lxntkof radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between then6t6h29d opl kfd xk.y4x.o 7q tires and the road for the car to make the turn?

  A car is moving withpbi296oy q szdrhdo31-p sm66 a constant speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What 63 ip oshy2pdzo-m6d9srbq 61 is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negotiat)zbm* -dfl64ana(ax):85d c xz gxt kce a 100-m radius turn at 35 m/s without skz8-xlx f cb an d6zxm5c4a*):a)t d(gkidding? (Ignore friction.)

  A horizontal curve on a bobsled run is b g2qh71lquir vpvs 244anked 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 oyplp0 3uo. yo*f radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banke2 p+u7mn n0qood 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 revolvingf(g+-;m rr;hsqa in9t uniformly in a horizontal circle of radius 0.(a rf-ti+r9nghq; ; sm500
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 toi7, e(r-0;c t)ryr qn:ztzs)g2xi nc he pit area, a race car accelerates at a uniform rate to 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 b-rr )rsozzy0:7 gt t(2, cnncx; )iiqelanks)
(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 mfcocltv)ody 2.6 xs( 4ass $1.67 \times 10^{-27} \; kg$ 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 forceqf.ms:f rla. * on a 70-kg person standing on the Earth, due to the Mo s:*f qm.raf.lon? 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 forcp jd ,tc4/o:cm3h6ysoe between two masses is F. If the masses are moved to half ofjtd: omc p3ch4o/sy6, their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth4iokwof6/;lm9dovtg hd7 x+) toward the Sun, at what distance from the Earth will t wod+m/lik4 x96hg;)oovf d7the 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 qmc1n l1qf4i9 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 foi :l9ix-i7zzdke.s t-1)wsn*q*sjgcr a "space-walk" at a distance above the Earth equal to the radius of the Earth. What-ngk i7-.s) 1:w*z xqdssl9*iti ezjc is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above : ds7a8:gfvr(k5 pzmxm 23fea the Earth's surface will the acceleration of gravit2dxrzafe :8m sp(:fgm7a 35 vky be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above llj-:wcr0h qd ws5 a5l4,*ntvs1xc b3its surface equal to 3 times the radius of Mars. The acceleration of gravity of the saq*av 5wn:5-blx0d4, rh llc 1scjswt3tellite, 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 grayz19ou9m* g h0ti8xr x*m1aeivity iszix919gio0muat*ry xem1 8h* $32 \; m/s^2$. 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. Thbd/ zy6h 1wbt:e Earth has radius r. If the object is raised to a height of 3r above the Earth's surface, what is its w h6bb:zwd /ty1eight?

  By how many newtons does the weight of a 100-kg person chaiye rvzyfag -:/3o2+qz t*,vcnge when he goes from sea level to an altitude of 5000 m? (Theey3 fz-o+:,/yvgit2z *vaq cr mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. Al9hloh) r/ddol369)x2m kqwanf 1uu 8 satellite of mass 100 kg is at a point 3r above the Earth's surfacen 6/lohk)8l1 x)m wod2hlu3q99fau rd. What is the satellite's weight?

  A spherically symmetric planet has four timv x,1qr)r49b hexz/8g8ljkayes the Earth's mass and twice its radius. If a jar of peanut butter weighs1xqb/z l)r 8gek h,ry8 9jax4v 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 they5i+mkds.- o4m7uf t-2 q3m 6z pvecpk same line, with the Ear4s2 po.3y k- 65umc7fzmmkp+t veq di-th 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 traeka/yej 9*oik g) *b;ansported 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 circul0cs- lr+ghg: v 22zmh nq0/umtar orbit about the Earth (i.e., it just skims the surface of the Earth). What is the02hzt2 g u nhcvsm:-l/0q+mr g 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 about +b4/honf oz y :9wrop1the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The fh4o 1yb9/pow +rzo:nmean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surfacen,iwd8 aev.sh/n2wbs59o+ bqwi +w- f of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radb.nne b vw,9iw-ofs 5/ 8qh+2isdwwa+ius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, ho8jij 3s6/gw3le 7oezas 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 Jug;c:n;xw/bf bpiter orbits 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 cy2p *r3mj- h3eqjacf . h8-g3 unrh)fjircular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long )rn -3f33jhaueqjhc2.y* hp jf8gmr-does it take moon B to complete an orbit?

  The planet Jupiter isi*o9ndp3t+o jef r.w)w:jo4r $7.78 \times 10^{11} \; m$ 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 Jupitsy0 a;10 gy*td 3ankzjer 12 years to orbit the Sun once. What is the average y1 n;aydjkt30* zgs0adistance from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)