Is it possible for an object moving with a constant speed to accelerate? + nbgskt*m* 5+br(dxc Explain.m x* gnkd*brs5t(c+ b+

  Consider a particle moving with cmj*3x 0-zy tr)meev- z+jck* gonstant speed such that its acceleration of constant magnitude is always perpendicular to -xt z +r-g)e*yc0 jmkjve3*zm its velocity.

  An object moves in a /:q ( dxc6. .boh0bue-f . hoxs3trnaccircular path at a constant speed. Compare the direction of the object's veloca:x.uhc . /qor s 3fcd(xe60to-bn.bhity and acceleration vectors.

  When an object experiences uniform circular motion, the direc0 sfo6 .jvb:pztion of the acceleration isbozf6sp .v: j0

  Consider a particle moving with constanit9of g3dw-n92mmk a+bx ;pkwl :tg33 t speed such that its acceleration of constant magnitude is always pg 3p:3i9a; mt o-t3b2x9dlnwmkkg fw+erpendicular to its velocity.

  What type of acceleration does an object moving with ctyp* mzqzr8732 tvcr. o+iy5nonstant speed in a circular path experoyi.8 2vr r3 tcz ym+7z5tpqn*ience?

  What force is needed to make anpj*5+;2j9 s8uv cv1rqi oxpst object move in a circle?

  When an object experiel6 k1e)i m8toynces uniform circular motion, the direction of the net forc)oiy6 1 tel8mke is

  A roller coaster car is on a track that forms a circular loopt9 m p,;iraaw1v )wr0m in the vertical plane. If thwr ; wp901vtiarma)m,e car is to just maintain 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 oen/l / rrh+ 0st53wup5j7mbeh n a track that forms 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 loop, what is the minimum valujrp u/s+re5e7w tn5hblm/h03e for its speed at that point?

  A pilot executes a vertical dive then followv2em r57u4 wnts a semi-circular arc until it is going straight up. Just as the plane is at its lowest point, the force on mnvrwte 7u245him 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 oze-.v3t5l ) q)pl-bsdpk sjn0f 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 radiusy vlgx0:siqel5-9rqn 8g.d6p 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 second time, compared.vle-q n5g:q08 si6xyr gp d9l to the first time?

  A car goes around a curve of radius r at a constanz+az* kmb8p *st speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal forcbz+ mka8**szpe 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 t8 7 ndpjm fxg;r4 9bzh48gpz5fhe road is frictionless due to ice, the car can still negotiate the curve if the horizontalg g ;pfmz5jxnp f4zbh8d48r79 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 hst34 t)la 10aycf6;mpux q6k +3uafbhas twice the radius fhu +claxy6tks4q1 0a3;b 6 ptua)mf3 of the other. The safe 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 turn on the Olympic bobsled track is not co;ak-n;qfy0lgq f w)e 1* tp7ynnstant, 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 do they do thip;fng *t 1y;qqe70n)lkf y-aw s?

  Is it possible for an object moving around a cir 6*n2.b1xp4/xsb kmray tqas*cular path to have both centripetal and tangential accelerbs 6*nqsmrk4 abpx2xt. *1ay/ ation?

  The gravitational force between two objects tbyqx (f-ji7w 4l*b ,lis proportional to

  The gravitational force between two objects is inversely pro5qxbr 7dx:32qxm bl) q9iwr,dvnf*.kportional to

  Two objects attract each other gravitationally. If the t ow )iwqukl 5)8c.wb7distance between their centers is cut in half, the gravitawwi8 o c7ltw5qu).bk )tional force

  Two objects, with mass1*wcy3 nrnta;rwu jyz6 yz.36 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 masse6z4n5ser 7hp ys $m_{1}$ 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 un:uoz,rsz q v,6hv.z g5iversal gravitation.

  Compared to its mass on the zb+ lpud*i+;*w9 ydcqEarth, the mass of an object on the Moon is

  The acceleration of gravityi8jb+2vy /8u dt*dr sx on the Moon is one-sixth what it is on Earth. An object v/ybudr+*sd2t88ix jof mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the xf(bd2;xqkhtj+ z8 )lm 6pl 1grocket's weight

  A spaceship is traveling to the Moon. At what point is it bemx gizq1e t06opdzho 8p221tb62u r6h yond the pull of Earh28p tzu66ip gd r2211 6ozx bq0mhteoth's gravity?

  Suppose a satellite were orbiting the Earth dsncwbmx y5) v(:0sf-just above the surface. What is its centripetal acceleratisdw0 vfnb- 5sx:c ym()on?

  A hypothetical planet has a mass of h:ixfh.+um4 vv alf that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet inxf4vvi+ h.u: m terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravit4mz0k njbw hopd,gpp547 r7/p y on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is t0n m/7pgkp4bzrp,7 o4 jhp w5dhe Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twp* ; qxa,zcco1ice the radius of planet A. If planet A has mass m,p1zc*,;ox a cq what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice thz4j1 d,mntq0h e mass of planet A. If planet A has radius r, what is the radiun,0 1djqmhz t4s of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a si vgjd7-x94ie 9d nrrl; tsz89pherical planet (mass M). Whi9 lrrx9;-iv iz89 dg7dt4jsench expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satelli,549lqjp3 ptip3pyia z ny8 ,ute B, and rotates in the same orbit. Compare the two satellite's a9i35zpi,ut8l3ppy pn4 ,yq jspeeds.

  A person is standing on a scale in an elex2,ixe fh x/7-4 ehmy6 .k;nstrnd vx-vator accelerating downward. Compare the reading on the scale to the person'i .rs/f 4ex,nh kemx7n2-xxd-thy 6v;s true weight.

  Who was the first perso-x5-sipddr : vhf5a.v +j i6ynn to realize that the planets move in elliptical paths around :-dii x6v 5h 5.fvn aysp+jr-dthe Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit around qw4g.9bp -a: 5,pxmxzkros/y the xqo4w9:bp5kr z-yp .g,ax m s/Sun,

  Let the average orbital radius of a planet be R. Let the orbital pe(spu vc3 lh a4e6zu1n-riod be T. What quantity is con1u4vh3(lauz-pn se 6cstant for all planets orbiting the Sun?

  A planet is discovered to orbit aroun z3np,g k*6g/y makgs7d a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 timesym*,nkg3azpg76 sk/g 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 "astronomicalh j/ u/z)t-riu unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the )z//jui-h u trSun?

State Kepler's laws.:l3o9:4uh st zukw(raf7 o5 dv

  List the four fundamental forces in naz * jyaq)3966,sf*7zn gfbjxaosgvrv +e h..uture.

  An object moves with a constant speed of 30 m/09dxs crri*rc tgsm,:q . 87j g3fnvp2s on a circular track of radius 150 m. What is the acceleration of the objec97r3i.nxr0dp ,8fg vgrs*ct 2ms:q j ct?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum c r grrg0eznfj* .8cu u28g:w7speed around a curve with twice the radius? (Assume all other factors remain unchangedugg7 c8rcrer.nj* 8zw0ug 2:f.)

  What is the centripetal accelerati0n)rimr tb; hptedu (f,too3*lhd8( 2on of a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike is moving 8o0e( (bi)d nf*;thr2h ,mt l 8uorpt3d.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locatef1u9 u8c8aikvd 0.200 m from the axis. What is thecka1uu8i9f 8v centripetal acceleration?

  How many revolutions,p7z2so 6na a,;pke 0:bibtwl per minute must a circular, rotating space station of radius 1b6 l0nkzw2p api7,;o,sa: ebt000 m rotate to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at 96:(bm/wg ax((uapv(4w;mi;vmxw yn v ..5 km/h. What is the centripetal force on the motorcycwww;m ba. / v(;m(a i( mu:gy4vp(xvxnle?

  A 0.50-kg mass is attached to the end of a 1e- cyp-,.dnzz.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N.-z ypc- ,.ndez 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 whirled in a vertical ciro-g ,kdh2az;6 )s7exg7t sejj cle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The ssz7t xja; sh ege)2,g-76j dkotone's speed at this point is given by

  A stone, of mass m, isms.;evwhqe 3hd k s q:h2: k/.r1yu+hy attached to a strong string and whirled in a vertical circle of radius rm+3y ked/q wyhes.:qk;1hv2 :h ru.sh. 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/s experiences an acceleratbr . he8hii8l+ u/*jneion of 4g when pulling out of the dive. What is the radius of curvature of the loop in which theelu8n/*8 bh.+jihr ie plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop imq39 oc *jxt,rcg9jn5s 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. How fast is he qcjcm95*jt rn,xgo39 going?

  The maximum force a pilot can stank jl3 k060 y6shwdz+syd is about seven times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, canss0h kzjk0y6w + 36dyl tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve 9 /:ll,pjtw:ten-/rddi, e ddwith the tires on the verge of slipping. How fast can this car round wl /ptdded d,e: /j:n,9-ltria 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 ofzit j.e7+o hcphpf ;1, 20 m/s. The centripetal force provided by frictif t hohp7+1pj,iez. c;on 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 a speed ofw2y(cy72 j35 eeqlhzr 14 m/s. What must be the minimum coefficient of friction between the tires and the r3lecy 5j2rhq72 zwe(yoad for the car to make the turn?

  A car is moving with gkf 4vu;)w u7ua constant speed v around a level curve. The coefficient ou)fk4u7;wuvg f friction between the tires and the 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 requrr.7e bgea -s,r jf- n+q(9sjsxr3q)mired for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignorsf3q-7se +jr9)mx-r j(e, r.nbs rag qe friction.)

  A horizontal curve on mcq )kkq8 thgzb 4.nzy46w1;za 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, banked at an angl y /.l81ckm2syo 0pseozy(si+ e of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is ban;jrkmj 1b(*0vg m xh5sked 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 v:m 1u l:y7cqiy8nm4d a string is revolving uniformly in a horizontal circle of radius 0.cnv :i:yqlum 14d my78500
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 x/f0.1 a8vnmb+igt nh*n)vu gcar accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circula) m*uh8x1nnfigtan+g/v b.0vr 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 of a proton(j ybe1y-im- r8okq, z 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, d xk*bgj sohy(d.d ieyf3 yry4/n)5 /6fue to the Moon? The mass of they kfr(id fy/*njb6h5 segy4 3xo.d/)y 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 between two mass7g4(mnpjkll1ua78. y jc p c(kes is F. If the masses are moved to half of their initial distance, what is the gravitational attrag.pk l7ca(mn4ju (87 kpycjl1 ctive force?

  For a spacecraft going from thew0 fkl.a 4 d ze/p9:pll,qao;w Earth toward the Sun, at what distance from the Earth will the gravita zlkppa4d /l.o9q;e wfl:a0w,tional 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:-ay:20nwt rzki c a)e $7.4 \times 10^{22} \; kg$ 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 "spa1-xjp x,u bs3pce-walk" at a distance above the Earth equal to the radius of the Earth. What is her acceleratiosbjppx - x13,un due to gravity?

  The radius of the Earth is R1 (97shzre aqbl3s3a y. At what distance above the Earth's surface will the acceleration of gravity a97r(sal3s zh e1b y3qbe $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its s-dqtg+xd t 4i5urface equal to 3 times the radius of Mars. The acceleration of gravity of the sg5 dqt -t4+dixatellite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some p3 ;lut2(r i.ln mzvojjtl-;ri5bmh 9+lanet's center, the acceleration of gravity is rm ;uz( 9- +;rt.on v ljlh5l3bt2jmii$32 \; m/s^2$. 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. T9tvu7y,/+,ldnsxw o xhe Earth has radius r. If the object is raised to a height of 3r above th txl7d+x/ouy wvn 9s,,e Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kgs.-s*c-t xm2pxg tyj3 person change when he goes from sea level to an altituy2*3ms g.t -ts- xpjxcde 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 1o da,h ;uw 8mr 5)m3gfo*psiw/00 kg is at a point 3r above the Earth's d5wf/air3go,pm*mows u8 h); surface. What is the satellite's weight?

  A spherically symmetric planet has four times the lc )f.b; ikxqn7zy) 6p)i2l duEarth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earthczyn)i .;6 )dbk7lu)x lq2 pfi, 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 li1l+qm4; k gasvvj7c 6.zgnmdvp6y 3j,ne, with thev lajm,n16 p.7 ;qs3dzyvg+v mgkjc46 Earth 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 Mnlr-9ijo 8qh1y;8jvc oon.
(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.eg*sxyvw,cj 2 v0 h2+io/ mb1sb., it just skims the surface of the Earth).gyj b+v,1s c2 o0s2b mwv/h*xi What 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 orru.q2ip1f wq (6-ry)iiicw:a tcs5t(bit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to m y( 2cwt i su c1qta6wf:rii5q)p-(.riake 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 is9 3qn 2ysn af5q4,qmna observed to have a period of 89 min. What is the mass of the Earth? (The mean r2n qamq n,53qyfsan4 9adius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamete s /+e994z-xoxdsxryb r of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupitdb(- vrb*6rwr er 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 circular orbits. o+dlr3j- h;el Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A tal3d+o- ehr lj;kes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter isagpf if0 8:-p5v3mj bh $7.78 \times 10^{11} \; m$ 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 fnc djr 0cfn6op99ewy-2+pp 0 is the average distance from Jupiter to the Sun? (The distance from the Eacjp0wn2r+e dco-990f p y f6nprth to the Sun is $1.5 \times 10^{11} \; m$.)