Is it possible for an object moving with a constant speed to accele0w+8f1 dmwdcq rate? Explainwq0cdf8d 1+w m.

  Consider a particle moving with constant speed such that its any.jcqkw* *jq7j..e 5d 1mwrrcceleration of constant magnitude is alkq w*e5 djwm.qj r..y71n*j crways perpendicular to its velocity.

  An object moves in a circular path47vlova7hqm: ea n:-s at a constant speed. Compare the direction of the objectl7m7 n4v:s:-aeoa hvq's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the a,i ah kfldeu( uv,6;(icceleration id(al h6vuue(;fi ,,kis

  Consider a particle moving with constant speed such that its acceleration of c8c)s)zxcr(y jonstant magnitude is always perpendicular to its v zs (cycxj)r)8elocity.

  What type of acceleration does an object moving with constant speedpn04fbs7oja75c t/ gh in a circular path experienc57pt/ h470sn baogc jfe?

  What force is needed to make an object c.+ a8kl;s sy+amh1 z-vkdxz4move in a circle?

  When an object experiences uniform circulahit/ o gqehhb x)2bl16 5xuwi4 gpo)(/r motion, the direction of the net force )2g/)e t4(h lub5q bh61iwx ophoxg/iis

  A roller coaster car is on a track that forms a ci2dam9l-lb bik 5( *u lh(fjgw6rcular 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 il*9a (-uhjl w dfk(i5bm6 l2gbts centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a cir5w7 s:nah(p docular loop (radius = r) in the vertical plane. If the car 5 sap:( howd7nis 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 follows a semi-circular ae .u0d 9hkq +le rugx,va6r;;:znqq r.rc until it is goqe: rhku,gnr0 9z 6evau;; . xlqr+q.ding straight 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 rady)9) 3howc wy/p xzns:ius $r$ 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 speed 5p9h+h+0 xqgqiz4nwd v. Then it goes around the same curve at half of the original speed. What is +hq054pw+hdnzi g9q x 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. T+z.e-wq( j-k7dpok r shen it goes around a curve of radius 2r at speed 2v. What is the cen-wp- 7j dke.o+(zqsr ktripetal 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 radius r with speed v. Iv6n +i3h7idx-d +mfmhf the road is frictionless due to ice, the car can still negotiate thminvd+xf63d i7+hh- me curve if the horizontal 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, bue5r9mgn4d lq4xb9c i d87jtt+ t one has twice the radius of the other. The safe speed (no friction needed to stayg9x m7tritqen b+ 4l4djd 958c 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 pr zn z62t) -9tit4v/ro-hzfz v g)al(not constant, but increases upward from the horizontal. Coming aroundor /) v-ztz6n tpvf) z(rz2ih gl4-9ta 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 cen1 hz+bo vju -uo(af)k.tripetal and tangj) u. 1bz(o-+ofuha vkential acceleration?

  The gravitational force between two t hn32zn .89fxiu+*+ib d(1chm vcactobjects is proportional to

  The gravitational force between two objects is inversely pro2 u;txjo e9:v.brvfj7 portional to

  Two objects attract each other gravitationally. If the distance between their c+dqn 6au4p deomg(h-7 ,7utgcenters is cut in half, the gravitationn heo-7dd,(apgtqgu +u c47m6al force

  Two objects, with mass m,,(95 :u gizcsnblwnes $m_{1}$ 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 masseses 16da)n *nhdg8sf)o $m_{1}$ 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 universa k2o14gox/y vzh0ayu* l gravitation.

  Compared to its mass on t ga;qf,lkh 2m+k0dzn, he Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon spk4:k, u;cryis one-sixth what it is on Earth. An object of4,kuyr ;spk: c mass
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 we +*b: kot1ixkm96qnmvight

  A spaceship is traveling to the d))vr5m-nk,f.y jj2mny 5chd Moon. At what point is it beyond the pull of Earth's g d2ndf, ymj5)n-cr 5yj)km. hvravity?

  Suppose a satellite were orbiting thi yxnvf-tyo (ha+.tli3/ )* che Earth just above the surface. What is its centripetaly- .h*hityvlcianf3xo/+)( t acceleration?

  A hypothetical planet has a mass of half that of the Earth and a radius of twicezgh r c;6 9:bejaj .u7shu/hy+ t+ z.:s6au79hy;ej/ j brhhcg uhat of the Earth. What 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 is one-sixth what it is on Earth. The 773bzk, /ng um qzor6 nbr.ta2radius of the Moon is one-fourth that of the Eab,.buo77 nkz23 mg/z ra6qrnt rth. What is the Moon's mass compared to the Earth's?

  Two planets have the same s 6-x-) mkaaziencm,3surface gravity, but planet B has twice the radius of planet A. x-za6 )-n,3kmemsc ia If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has twice thocz ,jy mo f.1:,pkpf 8o3c ,767z8ladichwyge mass of planet A. If planet A has radius r, what wpijg,ok1yfcp:fzc oc6, o 7l m7d8yzah. ,38is the radius of planet B?

  Consider a small satellk4 a7odb( *+tei:psa uite moving in a circular orbit (radius r) about a spherical planet (mass M). Whic i(7kpo *td:sb+e4u aah expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of sat;ph rs.zg:a,xq+8d dr ellite B, and rotates in the same orbit. Compare the two satellite': gqzrdhr+s8. x;a,dp s speeds.

  A person is standing on a scale in an elevator accelerating downward. Com r:mkq t/ )2hsu6yc6fco z*m0xpare the reading on the scale to the person's true wetc*rm/:6 ohu)c kxm26y zsfq 0ight.

  Who was the first person to r 3hgiu 4b opv af8 ux:e,*kb+gfnk)7,fealize that the planets move in elliptical paths arounx)4+pffug7bi 3fvh,u8 :n*e kba,k ogd the Sun?

  The speed of Halley's Cometd.vanb 4( fk(e, while traveling in its elliptical orbit around the ne f(d.bak4( vSun,

  Let the average orbital radius of a planet be q*rcb dh/lv ntx58d(2 uyru vidj.m /c699ds4R. Let the orbital period be T. What quantity is constant for all planetvn4rsl .9x qcc8d*dhd rt/j9uui/2(vyb d5m6 s orbiting the Sun?

  A planet is discoveredgp rbr xa*7w2l;07ozb to orbit around a star in the galaxy Andromeda, with the x2 0bz7r7bog*w;a p rlsame 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 defi9z3 gr;b5ii jsv+oam s2jzvn2tp 9;6kned as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance2s9vkz9 rjj5t a i2+ovn g;;b6iz3 msp from the Sun?

State Kepler's laws.wl2, 6sv;c+ic3 pvrpi

  List the four fundamevsvy l (t ywcb:pm,0jl );j 07kfk+cn5ntal forces in nature.

  An object moves with a constant speed of 30 m/s on a ceau2+yt ccj s6t*yh/6ircular track of radius 150 m. What is the acceleration ofes*yctuc26/a +jt 6 hy the object?

  The maximum speed around a lew61qgd j plv*4vel curve is 30.0 km/h. What is the maximum speed around a curve with 6l*14pdvqw jgtwice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the perimett bu.i9hv:l1ger of a bicycle wheel of diameter 70 cm when the bike is mov b9.g:1itulvh ing 8.0 m/s?

  A point on a wheel rotating1 u)1*gflsadd at 5.00 rev/s is located 0.200 m from the axis. What is the cen11uadl d )sf*gtripetal acceleration?

  How many revolutions per minute mus5 )5c lilo tc3cnr(de2t a circular, rotating space station of radius 1000 m rotate to p(ndcl3leroc2 t)ci 55 roduce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 1jb.bah- . 2j ,txn xlvokb3*j)3.7 m radius turn at 96.5 km/h. What is the centripejn- )bb .x*xl k.2oahj3jtvb,tal force on the motorcycle?

  A 0.50-kg mass is attached to the end of ak6op5xd( j7 i(9rpwal 1.0-m string. The system is whirled in a horizontal cip id6k l9jr(xwpo5( 7arcular 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 attached to a strong strinja :c8kov4,+ 0bnd wrug and whirled in a vertical circle of radius r. :4 jkvdr0 nu8w a,+obcAt 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 is given by

  A stone, of mass m, is attached to a strong string and whirled ;gwut7ri7 .jfm3rtf, in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 7r riug3jff wm7.tt; ,times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an ac l0u76lmr e/:nt tx-qcox4m yu*zq(3gp:zld1celeration of 4g when pulling out of the divml/x3teudyg-*q lx1ul6:p0zno q( z 7mrct4:e. What is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center o+a-* cg7 vsyl u.qdb4e8r*njff the loop is beneath him) of radius 3200 m. At the t+ sfdl c rv-j*q8uengyb4a.7*op of 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(.wa5rivk)z,f /.ksdsa u;1wh e6daz about seven times his weight. What is the minimum radius of curvature thi.)6kadzshsu,k/;wv e 1r( . w5ada fzat 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 with t0q fz9uu1qa l26 pzpu9he 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 e6u2uzqf9pa9 q10zl puach road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed of 20 m/s. The 2pvs,/o -d+uo2k vv hmcentripetal f/kpou,o vs2v -mv+dh2 orce 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 14wc8rwmetje0,a6,2kcc7 g sh 1 m/s. What must be th,ewc cs6,jt0wm1 kh8 arc7eg2e minimum coefficient 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 m4kin1uvin(6vx x.w xh:6hmrql( 7g: a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay ovv41gxl:76kin(rh.q 6 u:wx nmi(m x hn the road?

  What minimum banking angle is required for an Olympic bobsled to negotiate a gdx3so nn8d.5 100-m radius turn at 35 m/s without skidding? (Ignsddo8x .gnn3 5ore friction.)

  A horizontal curve on a bobsl v(etx4d 6c / qqx((yvns7;b/meg 3vcged 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, bankep167hkem/w pzy3ub qw j nb672d at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bankel,bp+s st bi,aludf. f/3o* +wd 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 fqtz++ xrj+6tend of a string is revolving uniformly in a horizontal circtzj6+xf +t rq+le of 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 unxhw*(82f y ,8j2y)t comceqp :sz7hss iform 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 sj7 *,c ) hsopczh82ye8(tf:m2s x wqyblanks)
(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 mass apl*icwtt)q,:b;tk ,, j: mps$1.67 \times 10^{-27} \; kg$ 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 fny6asqw kkv;p0 x)e:+ orce on a 70-kg person standing on the Earth, due to the Moon? Thyxan)0k keq s w+6p;:ve 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 the masse,r-px+*yp0w(g f zlx4esqq :o / x1macs are moved to half of their initial distance, what is the gravitational atqx w(g:*acx-0pfz xl/m,ry e +14ops qtractive force?

  For a spacecraft going from the Earth toward the Sun, at what distance frod cbh )-j)*zpdm the Earth will the gravitational forces due to the Sun and thbp-)) *dczjdhe 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 Moonl spno)n t 3n03xr+;tg 9rl.if 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 distancez w0 h4tb y2gqoad ,kx8,t6rh; above the Earth equal to the radius of the Earth. tq , ghyztoxk2a dr8;64 ,b0hwWhat is her acceleration due to gravity?

  The radius of the Earth is R. At what distance ab(d0x ;x 0goos3,bpfd tove the Earth's surface will tsdbx0pot( 0;3,fg xodhe acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance v6-9n tzboq jhg9,id+( ral9habove its surface equal to 3 times the radius of Mars. The acceleration of grh6 orv9g djlnq-z a(+,9b9htiavity of the satellite, 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 ac9bcu.8sspc 53k i3ffcceleration of gravity isfc sui5.f9 s3b8kcp 3c $32 \; m/s^2$. 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 radius 6 uu)6*he+ip.e6uhw2qdu b:;iuymagr. If the object is raised to a height of 3r abuuymq )ud b auh.iwu;6g26e6+eh i:*p ove the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he 3t*y*mye u+g31 q im4 imkge*fe(q7pvgoes from sea level to an altitude of 5000 m? (The mean radius of the Earth iste(u*kyvq 73mefg 13pqy gi+ emmi*4* $6.38 \times 10^{6} \; m$.)

  The Earth has radius r.w2 t:+r5vtlg: jobzg7 A satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satellite's wewb z5gt2l: t go7:+rjvight?

  A spherically symmetripu7z1i/9ta9c :d swubl5 n1l mc planet has four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the s1maldtzi:5p9ubu917/ncswl urface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun a1-dbj.rh4p x gll lie on the same line, with the Earth between the Moon and the Sun. The Moon has a mass p -4hjd1bxr. gof $7.36 \times 10^{22} \; kg$; 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 tonsz73 /( c bj0/1l7hby zgedtjeak*x - 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 orbit about the Earth (i.e., it jus9gb wyy q6 9a,vtrq,:ut skims the surface of the Earth). What is the speed of the s g y, 9,69yqt:rvuwqabatellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular*2 sxun yb/2if)lmbb/m73duj orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? (The mean s7bmbl //)u* f ud 22mjny3ixbradius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earthvkd,y9x91 eo u. It is observed to have a period of 89 min. What is the mass of t9ovu9, xyd1 ekhe Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital diameterxoy8+* igm 3e ,tm ooq,;:kxvr 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 ty2 g,)e;/gevmb9zw hyhe 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. Moon A has orbital radius rh/xd9h1h2 xli , and moon B has orbital radius 4r. hix2d9/1hxh lMoon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is*qn 50q-rz /s :oju(qkay)*hsj cr8ee $7.78 \times 10^{11} \; m$ 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.,m;mho x7 qs k85d3opkp r*9p6jiwrm is the average distance from Jupidr qow5 o,9krk;p63 sp px.87 j*mmmhiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)