Is it possible for an object moving with a constant speed to accelsda) )kxk(-x lerate? Explaikx)s)ladxk -(n.

  Consider a particle moving with constant speed such that its acc ihv2s8yxyv4( eleration of constant magnitude is always perp4(v ysy 8vix2hendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare the direcr8x0agp k6yt9 5x xtj2s6 ek2gtion of the prxxt0j 86yge g x569sk 2ka2tobject's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the diro+ c0q, h f9/fo* /4bzf xokcf;uw)rlhection of the acceleratiqhofo/ ckfb +)co *,xu;hf0 4f z9lwr/on is

  Consider a particle moving with co hr+p kx9j84 pt;.5gtpj b5rlynstant speed such that its acceleration of constant magnit;rj t4y plg9x.jhrpkb+5t5 8pude is always perpendicular to its velocity.

  What type of acceleration does an object moving with constan xyk;j6oqmffg 7x zq ;j2x*k6y*v+cd5t speed in a circular path experienj6 *k+ydgy;zq6fqf;x xcm2xvjk5o * 7ce?

  What force is needed to make aq-:oaxc/be +a n object move in a circle?

  When an object experiences uniform circular motion, the diio:d*eu+bl t- rection of the net forbdl:oi-tu +*ece is

  A roller coaster car is on a track that forms a circular loopt*fhx)g,yl /y in the vertical plane. If the car is to just maiygl/)yftx ,h*ntain 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 forms a circular loow 1.v)ysyv za6h0h6i)jkry e)zk ro56 )pf9gxp (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the top of the loop, whaf ky 5kj )zi6h1ghexsvz 6y)).0w6 yr9rao)vp t is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc uit)tc :isa1g ;m7p ,sgntil it is going str1tpci s;s,tg)g: m7 iaaight 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 curvf7) h77q cb(mw hm2zxw,n sj;ee 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 atngac5p s0 a:hzv97b +sx3q6mw a constant speed v. Then it goes around the same curve at half of the originasbc9 05shq 3axa6vn m:gpw+7z l 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 curve3lkuv25ud8tl ltd j7 7 of radius r at a constant speed v. Then it goes around a curve of radius 2r at speelj7v ldkut utld85372d 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 of rbkyd. 6 pm7q)c ,jo3ab+e)vel adius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal compo)b 6.)m +ye,pcj beal7qd vk3onent of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run aret gqlwi8:qxt b9.rd83x3pdu 8 banked at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radrpq lxixutdb3:9w 83dq88 .gtius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobv+;6oe/xotp7 ctlg k (;9ileqsled track is not constant, but increases upward from the horizontal+qo(l7ixgeoe v tp ;6;cl kt/9. 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 circular path to have both centrd(i:grw6s 3xd jzv93t ipetal and tangential accelerationzgr:tv dd3i w9sj6x3(?

  The gravitational force between two ( 6geh1ap 628en60klhqza yvmim* 1 dqobjects is proportional to

  The gravitational force b x5;n 26wmx:ic4kx hhmetween two objects is inversely proportional to

  Two objects attract each other ,t*4 rk)qhc .cm ,yheegravitationally. If the distance between their centers is cut in half, the gravitational foq4crch,h*t kym. ,e )erce

  Two objects, with masse+; dz; k9.gxhyeslp 8oqn,/jls $m_{1}$ 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 a:zh+e /jv2zd 97egl g$m_{1}$ 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 univs6zvt71amr2gk-8 qq0tk ee0j gul9;c 5tru0 rersal gravitation.

  Compared to its mass on the Earth, the mass of an object on the Moong/;iq:bd) /ctqco x fw0+gso3 is

  The acceleration of gravity on the Moon q*.ff4hqbfj 21 ( gvd4rqh nl*is one-sixth what it is on Earth. An object f4bv*qfdgj24qhh(rf n .q 1*lof mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the ro2 usm.r(9oi jontfub (9m 0i)epm)ah: cket's weight

  A spaceship is traveling to the Mowv;/p4we wk6 0 ).lzxgc;yt+hz8 nmaf on. At what point is it beyond the pull of Eartht pz.mhcx wy0e/ )k;6la8f+gzw;4v w n's gravity?

  Suppose a satellite were orbiting the Earth just above the s05 clw xubbovm;,77bturface. What is its centripetal acceleration bm vuxbct7wo 57,l0;b?

  A hypothetical planet has a mass of half that of the Earth and a rwhvfc095f)gp u 48ur gadius of twice that of the Earth. What u4 rf0g fuvw5ch)9p8gis the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravityin zn-xhp(io +2wc74j on the Moon is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of thei+ zwh2icpn(n7 4xj-o Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same s1ovq5x:-th*4zua 3.ns oi f ah(1con turface gravity, but planet B has twice the radius of plane1oun-cs ahx(4f3h:5ov .qzit1ota * nt A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same su*5v)z j/pt p i6omdyl(rface gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of5pi mytpo(ld/6j z*v) planet B?

  Consider a small satellite moving in a circular orbit (radiushfcdsa 0p pz3b +luz43+ jxx63 r) about a spherical planet (mass M). Which expression djc64+bpzx3p fzus h 30a3lx+gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the qzx4ew2va3+5z,tu 1vvys (oaw0 h/ tlv*nm, xsame orbit. Compare the two s vmx+w5x/tn,yv4zaatl v02s3(q *1, zew v uohatellite's speeds.

  A person is standing on a scale in an elevator accelemh,*r5ft 3 szi2a3s parating downward. Compare the reading onm5*z, sat3rishpaf 23 the scale to the person's true weight.

  Who was the first person to realize that the planetyd pmtpg;3+xdv9d/ : ypjz-j8s move in elliptical paths around v3+dg/ -d jdx mz:; 9yptp8ypjthe Sun?

  The speed of Halley's Comet, wh 9ad(5swyt lyaol 42dwt)33ivile traveling in its elliptical orbit around the Sunildt ytdao9l5a)(s4y 3 v3ww2 ,

  Let the average orbital radiubua*/zm*sw 2q s of a planet be R. Let the orbital period be T. What quantity is constant** aqsub/w2zm for all planets orbiting the Sun?

  A planet is discovered to orbit around a srn1 s . (h1xj9ych6ffetar in the galaxy Andromeda, with the rex c11hhy9n6jsf .(fsame 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 period?

  The average distance from the Earth to the Sun is defined as one "asthu 53)t7fcfveronomical unit" (AU). An asteroid orbits the Sun in one-th)f3c7uv tf eh5ird of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.c g3 1t qi;;v2lkl8cvmbv5f7ho2a1se

  List the four fundameny - :gqxn47zortal forces in nature.

  An object moves with a constant speed of 30 m/s on hsh7-0fk foo4:ib.crw o+rp/ a circular track of radius 150 m. What is the accel:0ob oihwp4 ffc rh7-s/r.+koeration of the object?

  The maximum speed around a levex-vsn(bies-)l3m d 9g l curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain u) l(sxem s n3v9g-di-bnchanged.)

  What is the centripetal acceleration of 1zkr+/n woq-/ynx 7owewh pimekl *50y7 k-q* a point on the perimeter of a bicycle wheel of diameter 70 cm when the bike is q/y+krhekq15nlw e*7owipy*k-/- w x7ozm0n moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is locatkg8 3c(au(xiy h 0aa o.s.s-fyed 0.200 m from the axis. What is the centripetal ac-ascy80o .xs (uh.3if(aya k gceleration?

  How many revolutions per minute must a circular, rotatie/ i *x5vw cqsmc- *)nkysw85fng space station of radius 1000snc/wk *e8) s 5yi5mc-wfq*vx 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 tu,5no;/urnlczi)d l; wkpnd5n wz 8j2 0rn at 96.5 km/h. What is the centripetal force on the n2 wlk )nz/5 ui;dw;c8rzn,n0pl5jo d motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m stric 9dkxp (4esyoqr7bwe*it)5 *6v/canng. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed of thctyveo*)qxwrpe*a d5(6/ci 7kb 4sn9e mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirlez;xer 4(0f,4tsbh, ( r vuimoad1b,vcd in a vertical circle of radius r. At the ex,c0uifr,hzte ,4 as((;ov 1rb4dmxvbact top 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 stone, of mass m, is attached to a strong stringtc 5(x9k3iduf and whirled in a vertical circle of radius r39if(u5ctk xd . 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 axav :wci7 an7/n acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which a/i ax:7w 7ncvthe plane is flying?

  A pilot makes an outside vertical loop (in which the dp+g0xh 8b.aaow4no( 3ve5cxcenter 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 (xbnog4+a.v dohc wpa 0x3e85his normal weight. How fast is he going?

  The maximum force a pilot can stand is abo be50*xhfkczr /3qvs6- xh6x;d vv9g mut seven times his weight. What is the minimum radius of curvature 3ehvzrvx-c; 96m/ b*6v qk hx5f0xsdgthat a jet 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 horizontal curve wi874d3g p5y,z q2vjpc nhfuz g*th the tires on the verge of slipping. How fast can this car round a second curve of radius 25p jg8zz3 p*v yu,hnfc 7q4gd320 m? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of rs;u: kd*t d p6sou+d:jadius 50 m with a speed of 20 m/s. The centrjoks:+ud*dt6d u s: ;pipetal 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 su rj6bo,m c;e,u;tn,nf5 )jvcxjazg4k:9p 7x peed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to make the tur uj6;5,r c)mcx fn7bj4z ;akpg9 ,jvt,o exnu:n?

  A car is moving with a constant speed v around a lev g14cdp0v hwd2yg)0uyel curve. The coefficient of friction4y p0u2h c0)1yvdggd w 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 rd12ed);5ve(odo.ikp,r2rwz uqok7 gequired for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s wi ro oewe)dk5.oz;k qpd,g7iv(u2d r12 thout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run irl3t)2l 3xlg-cmqr h8s 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 agqtwwj (i8r 9b0cc: +v:jgr2t3 u )vuan angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b66 ,u:ypj1 rn fl3abzlanked 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 reo6; rm o/nmc4ovolving uniformly in a horizontal circle of radiorocn/om m6; 4us 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 rate tvh2fv.3aata2 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 blanvf2t2.3ah avaks)
(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 prp1 8 /s fkt:ww qisd52b2zg+ijoton 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 7-8d5oqg7mi zv5y 3zy bfy.1o vmy:xwEarth, due to tq5mvy7yzv5 oy io3:m.17x8dzgfwby- he Moon? 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 force between two masses is F. If mxy 62 g/tu(e1gbew6dthe masses are moved to half of their initial distance, what is the gravitational attractive force?16u wde xggy(/t me62b

  For a spacecraft going from the Earth tom8klfixo) kul t t-n0.6d2mf,xqq+8 wward the Sun, at what distance from the Earth will the gra82mf+wofqmdkiq tlu)860t xxn ,.l -kvitational 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 ipn ) he+19teig,gy zgmqq3 :;cs $7.4 \times 10^{22} \; kg$ 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 distance above the ch04 icyp7g-n r if;m,b*uef.Earth equal to the radius of the Earth. What is her acceleration dr; if* . e-cn cuyg4mfi7,0bhpue to gravity?

  The radius of the Earth is R. At what distance above the Earth's surv/uo om; cyt7b4w 6:q*st9m wrface will the accelerati*v 7m4:9 mu6 b ywwttc/qsoo;ron of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surff(lz qpff3*j +bytmwn 3 .41vbace equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the suw+ bf .y43mfjfl n*p(t 3qvz1brface of Mars, is

  At a distance of 14000 km from some planet's center, the acc4oyna;w dlx-y8k rkdrt 7zr)c9x2 -p;eleration of gravity is x2rdx-koazn89d ;yrt) cp 7kr;l-wy 4$32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N on t wht 0k.f:c9e w8tvi5ihe surface of the Earth. The Earth has radius r. If the object is raised to a heigh0ckwtw:i9iet.v f5 8ht of 3r above the Earth's surface, what is its weight?

  By how many newtons does t9x9 u iexv 0*oar(,vtzhe weight of a 100-kg person change when he goes from sea level to an alta9* tvux(i,9exo zvr 0itude 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/ 9l8x) zt0g2(fn*c g xqcdgpt 100 kg is at a point 3r above the Earth's surfacez2ng/xlc9q c8*dt(tg f 0x)pg. What is the satellite's weight?

  A spherically symmetric plat t)aw-ny 1v1knet has four times the Earth's mass and twice its radius. If a jar o-t ynv11 tkwa)f 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 Mo mh5ap*zn jg:x74j6zn on, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mass ozmx :aj7gzhnj* 4 p5n6f $7.36 \times 10^{22} \; kg$; 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 trmhl,l ,l/ *wfz(;iopfansported 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 circular k 0 .e5yncljzam1;:ky orbit about the Earth (i.e., it just skims the surface of the Earth). What is thee0;1zy: .nmkcjk5aly 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 the Earth (i.e., it jzpyfk y1tm-/0)g ch (.k ;ws4qjndu/dust skims the surfac1fk4 )c.0sz;hwy / ygkpj/ ddu-mqt( ne of the Earth). 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 circular orbit 230 km above the surface of /s8w kw 9jo,h)utf3hi the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the Earth is t8,ku/w ojwf)i 9hh3s $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diamete c.y 1s2gi+xr 5d h8oo2usz*fir 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 p icd:p9fa 9;tqlanet 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 bt b +0)el6u3aurmj cxpo6.6uorbits. Moon A has orbital 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 an orbejo)u6ub 63t xaub60+cpmr.l it?

  The planet Jupiter is py xod3 az1an5k* 9lm)$7.78 \times 10^{11} \; m$ 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 6k5x4 3bfmfry to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance from the Earth to th5y ff6 3mb4xrke Sun is $1.5 \times 10^{11} \; m$.)