Is it possible for an object moving with a consa( xooxm+v8l5vah olse75lw k e;v1,5tant speed to accelerate? Explain.oma+5 vh7elexs5xk lvl,1oo wa8(;5v

  Consider a particle moving with constant speed such that j7b ubc *.6tkvits acceleration of constant magnitude is always perpendicular to its v* 7u cjb.bt6vkelocity.

  An object moves in a circular path at a constant s m ha8c5n,g6 gq5iorpra/w;m0peed. Compare the direction of th0hpr5q gga/m 5wrm6iona , 8;ce object's velocity and acceleration vectors.

  When an object experiences uniform circular +fsg g)(jn,u zyzp9*omotion, the direction of the accelerao ,p) z*9syggzj+u f(ntion is

  Consider a particle movylyphrl+p,:6*l4 /gyho yl 2hing with constant speed such that its acceleration of constant magnitude is always perpendicular to its vehop/4lyg l*yr:ly+l yhh2p6 ,locity.

  What type of acceleration does an obd : zzb)ej61kx zfbz(:,g 7cb,bf-je0m;ljyuject moving with constant speed in a circularub;e0,bm6dz1b7gz,z(jj x flyk)j zc: ef:-b path experience?

  What force is needed to make an objq02-5sg 9/ mz6msd2ploaatlkect move in a circle?

  When an object experiences un/d9u p8mh7 xf z1lp2og3axc*biform circular motion, the direction of the net force iszbafo3cup9xld/p g17 2 *hxm8

  A roller coaster car is xz1t e)ia.tjtftiu7a3-*+x o9ndt ) q on a track that forms 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 centripetal accelerat-ut*ad+t.onj7za )x3 )e9 xtq ifi1ttion at this point?

  A roller coaster car (mass = M) i jiccibn5 53w /k8rvu2s on a track that forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain con2ui5bji 3c8 v wcr5k/ntact 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-cpsro1shnh(3 0rfp3o bq z-(/s05og ryircular arc until it is going straight up. Just as tsh-oqpsfr5b3(g0 rsp1/o3 h0zy rno(he 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 currf 5 6yhyarr- 4 o *e;m3wnczak-edrk3we;v66ve 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 radius r at a )ev1a.desbr *l at-v)constant speed v. Then it goes around the sat)vd)1 l e.*be -asrvame 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 to the first time?

  A car goes around a curve of radius r at a constant speed v.bim5u4r(:8z9dmi e(whjq a2yq-+z xnn+a s-a Then it goes around a curvexa+zd+5j2 iymau-wn bi9 (qz( : hnqem-a4s8r of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, compared to the first?

  A car of mass m goes around a banked curve o ij squxifk*qg :z+*96rwsa+ak)35fcf radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of 6)i :*gj*q3axsz9 rcs5a +u f+wkkiqfthe 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:x d*k)dylyl+yv91ory :)vrbb1 ;y nk t one has twice the radius of the other. The safe speed (no friction needed tkb yo:1y *nvlrr1v:;ybx9)dyylk) +do 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 545sva f5sagb sc4*v)kvg: iyconstant, 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 doca5 4 g)5v5b4f:skvig s*avys this?

  Is it possible for an object moving around a circular .; xv2c+t j(l,qbrg* 2hkx excpath to have both centripetal and tangential accelerab kt;e(c+,xgv 2.*xqcxlh2rj tion?

  The gravitational force between teoh 5y6 g)t9 kufw/4ylwo objects is proportional to

  The gravitational force ;i3r fdx i.vu/jx r(.:3rk hvgbetween two objects is inversely proportional to

  Two objects attract each other gravitationally. If the 9, irbco/x9rd;pugwly48b 3h distance between their centers ispb9dx4l9io;ry/c rw,u 8hg b3 cut in half, the gravitational force

  Two objects, with massesrjm/g6vs4h 8 45wipwi $m_{1}$ 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 1dkpgaqz :-po):j6zd $m_{1}$ 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 universu.f/fi-x:i z7em,,wgx0 ) qvh: nwton al gravitation.

  Compared to its mass on the Earth, the mass of an objp(9fnps.e/i t ect on the Moon is

  The acceleration of gravity on the Moon is one-usl8tu+ wi *(31/xzueitbs8 nm;;jt y sixth what it is on Earth. An object of masssexi+w 3(s; ti 8;mjbt yn *8ul1t/zuu
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surfzbmp; ( x8u( cqzc0 wgn/8-xtzace, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pual( q/w5fk7ok;* pe mzll of Earth's g5 * qaplfo;kez(w7km/ravity?

  Suppose a satellite were orbiting t w-niu, p0f,y r:2e 6qyklpap8he Earth just above the surface. What is its centripetal accele pk-,ypueiafln8 ,60: q ywr2pration?

  A hypothetical planet has a mass of half that (sqo.:s) k8 qs5;gdjf7+shleo f1jxpof the Earth and a radius of twice that of the Earth. W qhpj+l;f1 d8)(5ogfxsqss 7.oj: ske 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 zcuue;oa3l3 8oohn 6r* e h by1 7zp9k8dmc6,ais one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's masl*e7keu8 1c9h6yzp;no3za,uc86dh 3a o mb ros compared to the Earth's?

  Two planets have the same p+l z l.7za/znsurface gravity, but planet B has twice the radius of planet A. If planet A .pan7lz+zz/l has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B 3rjw/8 ljvj ln79ot9vhas twice the mass of planet A. If planet9o98tjln rl vvw3jj/7 A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circuyy9 wvn 1qta*ru8iqg 4p3f*q;wqr,. ylar orbit (radius r) about a spherical planet (mass M). Whi4 q 1awvrwufyq*r.nq,; 3 *i9ypq y8gtch expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit.7/twgv rh -zu- Compare the two satellite's sv-ht 7rgz/ uw-peeds.

  A person is standing on a scale in an elevator accel2.00sl* hsezfb y ew5nerating downward. Compare the reading on the scale to the person's true weig0n * whe sl5b0syfz.e2ht.

  Who was the first person to realize that the planets mozglg1j+, v1z0spe z6 hve in elliptical paths around the p l,01esv+ggjhz6zz1 Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbish-uxcuqkg1 njs1/y) yr 1i)8t around the Sun,uryg1ynk1 8 jscisx 1h)/)- uq

  Let the average orbital radius1(eeob ba/:d r of a planet be R. Let the orbital period be T. What quantity is constant for all plan oaee1(b:/ rbdets orbiting the Sun?

  A planet is discovered to orbit around a star in ob7cyb53dr wdx);s zba(/ md1if(-wy the galaxy 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 oo3 d5firw(( bmb 7/1ys) -c;zdybaxwdf revolution of that new planet be, compared to the Earth's orbital period?

  The average distance from the Earth to the Su kap .qdc0;;iv-t 4bz 8k4amsgn is defined as one "astronomical unit" (AU). An aste ts;.p-4k;cmaaqk 48 zgdb0viroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws. f8 q 2f.3xrjs:ju 0npgo/t;jh

  List the four fundamental forces in 2pems2 zel7 j2nature.

  An object moves with a constant speed of 30 m/s on a circular track of radiukz (,v- nzx2bzs 150 m. , 2(zbzvxzk-n What is the acceleration of the object?

  The maximum speed around a level curve is 30vu2)c. xwgfqbd1 5r z6.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain unc urg2.q)6fwc 5x vd1zbhanged.)

  What is the centripetal acmvm c3-d hz00;1 upn 7kf7ythaceleration of a point on the perimeter of a bicycle wheel of diahm0a3tym;kvpdn - z1uf77 h0cmeter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rg7r)bj+4s tnyotating at 5.00 rev/s is located 0.200 m from the axis. What is the centripetal acc47 jn +ybr)gsteleration?

  How many revolutions per minute must a circulwd10 ga iek7,zar, rotating space station of radius 1000 m dzgeiw a7 ,1k0rotate 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 radiusis3-6nhz 1z ux5mb5kl a:y5q,lbb)yx turn at 96.5 km/h. What is the centripetal forci55k-n1huz3b z) 6mbyx :5bql l asyx,e on the motorcycle?

  A 0.50-kg mass is attached to the end oedo;i uqy0; dex3k7y 1f a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can with ;eo ue7yk xdiqd;1y30stand 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 anp 9(oldb4 h:bfd 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. The stone's speed at this point o bdf4bpl( :9his given by

  A stone, of mass m, is attached to l.:yrj cd5 w)2xj;n otnf(g1e 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 egn1c. f2j rwdoxjtl; y5)n( :stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration owgv3ed7zoxlr2 h o0 +/m3h tn8f 4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane rd htwhxg/v0 327m o8zoe l+n3is flying?

  A pilot makes an outside vertical loop (in which 9vcory0.8w vuthe center of the loop 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 normal weight. How fast is he go8cu09 vyw.voring?

  The maximum force a pilot can stand is about seven times his weibbquzd4 e fqpa .4i*7(ght. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250qe db7 .p(4iuzf*a4qb m/s?

  A car traveling 20 m/s rounds an 80-m xe(6kmb 7*l bo7v t;myradius 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 eacxt67km 7ylbo(e ;bvm* h road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. The censw int1d9o+x0jn j7s-(a*zp ztripetn+spjs0t 9 i-1z(nwdo 7xaz* jal 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 m at a speed of 14 m/(erzmf5 (/ugeki wfe*pi ) )k0s. What must be the minimum coefficient of friction betwee*k)( ) ifp0/erem fzuk(5wg ien the tires and the road for the car to make the turn?

  A car is moving with a constant speed v around a level curve. Tfe)irwo1 ,5k7sbwgb1 he coefficient of friction betww)k oriw1gb sfb51,7 eeen 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 required for an Olympic bobsled tv42fwwxc0 x0nvhmy025lwe3 o o negotiate a 100-m radius turn at 35 m/s witx2w 5cln 2 vm0wwyhovef0x43 0hout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banke/pv74j ygm dw7d 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 5a3 usoz,gt sg fvy;c4*/9gcb 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 banked at5 a2 tftp gb8)b/6-absfzcnp * $45^{\circ}$. 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 uniformk*( fis9x0vcy dwq6lof ec1 :8ly in a horizontal circle of radiuse sof9w6 dl0*q v81yc(ic:fxk 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 the7d4x ugp(v(z4;pm9 hp*wy enn 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 inhv7(n 4;ngpp(zuy9*pdm 4e xw 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 oflp1 dwt 3:v;f4ytabs 1 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 gravitationa tbllp579y7 pbooxb+w+l. v4il force on a 70-kg person standing on the Earth, due to the Moon? T+b7y95 wo4ll7.x+polbi t b pvhe 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 force between two masses is F4rka;:imw9 on . If the masses are moved to half o4m rkon9;: iwaf their initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what distanc 3vsq--snh+sxc-6luo e from the Earth will the gravitational forces dn6x3-qu-vss h+-o cl sue 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 )/rrsttct / uhegolf/5.s5rz 2 e/ 6to$7.4 \times 10^{22} \; kg$ 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" aoplk mj eimt7(b ,ui(*/vf;a,t a distance above the Earth equal to the radius of the Eabf p(m t(,a7;lkm*vji ,/oue irth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's sr( d)ira3wp h0p, hp o)wck2;surface will the aca wh0h,ckrp;po()2rwis ) d3pceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 time2p-lpd df9v:ps the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleratio9l:vp dp2fd -pn of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of grayen8t4eu7 e j/8o4jluvity is j88u nej4y/oue4t7l 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 N on the surface of the Earth. The Earth has rap*z ( gsl*,ejfurm1tj q:n 3p-dius r. If the object is raised to a height of 3r above the Earth's surface, what is itsfmls*-3q:n gzep *uj ( ,jtrp1 weight?

  By how many newtons does the weight of a 100-kg person change 3 .zzs cahu/9owhen he goes from sea level to an altitude of 5000 m? (The mean radic a/9ouzs z3h.us of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A sbp f7 e) v0k0go1fx( 9auohh-batellite of mass 100 kg is at a point 3r above the Earth's surface. Wehg)kp u0ahf0b (o7b o fv-91xhat is the satellite's weight?

  A spherically symmetric planet has four times the Earth's 6fb3 vhqjwvp .m;.hb5 (kp4 jhmass and twice its radius. If a jar of peanut butter weighs 12 N oj fhbm5;vv b63.w(p p hqhjk.4n the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the svl julfv:2/ ,Moon, Earth, and Sun all lie on the same line, with the Earth between the Moon 2/v:jlfv ,lusand 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. qpy mw92i4o2 y
(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.e., it just skimgm v +6e;ew 93zxr7fa+rb/a pys the surface of the Earth). What is the speed of the satellite? (The mean radius of 7+ ya3a x frerpe+z6;mvwb9g/the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit a** u1x;mgaqob q-q8cnbout the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution arox;mn -uq*qa8o*1g bcq und the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in cir z-.w urw,sc-kcular 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? ,w -wsuk .rz-c(The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameter: zqpmt2i( lj1 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 aoi33jvknhgwy h52l62 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 orbital 5 f )muinsdd65:pqd5,whz/hr 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 complete z f:n/,r dus5d)h ip56hdm 5qwan orbit?

  The planet Jupiter iu w h cijl4nu17gp8s93s $7.78 \times 10^{11} \; m$ 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 J*osc htu/ha,0 cp(2 cnupiter 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance froc c*h/0,s (pn2uat hocm the Earth to the Sun is $1.5 \times 10^{11} \; m$.)