Is it possible for an object movin1enm 8s01 re.+c;gha n p,ebuwg with a constant speed to accelerate? Explain.sg,h8mcnue +e 10pb wr.;1nae

  Consider a particle moving with constant speed such that its acceleran;hl,b 7 u 7;lc4hihgption of constiu lln h;pg7;c,4b7hhant magnitude is always perpendicular to its velocity.

  An object moves in a circular path at a const5 obxpc 2y 7s.bt )dk7nw)zjh0ant speed. Compare the direction of the object'skws)bt 7y2 x)5nh7z pdjcob.0 velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the accelp8 5jmx1asbae7e b: p)eration bpae8bp7j5axs:e1 m )is

  Consider a particle moving with constant speed su,/cxpd 3tmssl1*x3odb(x( luch that its acceleration of constad*oxcb3 3 tssmp (l ldu/xx1,(nt magnitude is always perpendicular to its velocity.

  What type of acceleration does an object moving with constant speed in a ch wcli( .m :sd1p9jbdjh7+xq/) b d/ciircularj q cjwb:m( +sd7x.1i hc9b)/lid/dph path experience?

  What force is needed to make an om70hxr8l 8 ne6w-eiko wym v85bject move in a circle?

  When an object experiences uniform circifd5hc/v0. p cular motion, the direction of the net force 0cpif5./ hvdc is

  A roller coaster car is on a track that forms a circulqrm9;n0kxc4j0gz 6 e*t tjq;l ar loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minim ;x qqr mk4ntlc0z6;jj 0*9tegum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track tqtt;9u(ch q6 +vcj 3sihat 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 thqjq3sc(c ui ;69 htvt+e minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc u1d2exm k:-gh hntil it is going straight up. Just as the plane is atm d2 xk-ghh1e: 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 ra:tl );i6g t24qmlnr1 u*;yjs2l0h 7jndd tgf pdius $r$ 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 cono-txw/,0+ p*p mmsu0 :boh kgsstant speed v. Then it goes around the same curve at half of the original speed. What ip0s bs gpxm0-to/h:ou+m*w , ks 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 spe-cu60hxlgkjds j ./r) rvj,z2ed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, compared to g/vjulhj r .6rz x,2cj)sd-k0the first?

  A car of mass m goes around a banked d3 )-hu x 3,wztcfi,yicurve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal comc tifi)hywzx- u3d ,3,ponent of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves on a hee *x7x-tm n+9elg2g bobsled run are 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 radius curve is v. What is the safe speed on the 92 ln7gx-et mg heex*+larger radius curve?

  The banking angle in a turn on the h0-o-qb 5a 8kvvj knma3fy z3wfx2q5(Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled teama zk3 v8oyhaf2kmj5b q x -w-f(0nqv35 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 h 6g6 7,syq4 lvdzjoqp.ave both centripetal and 47,6 zpvq6qgdojy sl.tangential acceleration?

  The gravitational force between two objects is proporu4c:vfqmk 7 m( g0(wemdjg /:btional to

  The gravitational force between two objects is inversely proportional t x-niv,fw8av-u w wce4/j +vo.o

  Two objects attract eaq;y b;*cl )big2n.pl zch other gravitationally. If the distance between their centers is cut in half, .; izby* lbp2;lg qn)cthe gravitational force

  Two objects, with maf6;rtg qwwy+2 sses $m_{1}$ 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 massj/(qxk aa7,ziv. b,c pes $m_{1}$ 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 univerwrbc-yrxl75t;(4 jtj sal gravitation.

  Compared to its mass o5me(p(s)ay d t d r2litqq:*p)f79bb mn the Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon iwnj4 wnlu4m;l5g x-:bs one-sixth what it is on Earth. An objectbl -gnn45x4 ;wmwuj: l of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the go0fr97c1tc+o/ i8uz9bs x fyrocket's weight

  A spaceship is traveling to the Moon. At w 6u3zjwzpq,e ci7:tm 6f;ueaf*8 7pzwhat point is it beyond the pull of Earth'wm6 e3fe; u c:azt*w u7f i7p8,jzpzq6s gravity?

  Suppose a satellite were orz(t*nl e-3 z1 lbwq-kxbiting the Earth just above the surface. What is its centripetal acceleratio-tx* 3zkw b1-el(q nzln?

  A hypothetical planet has a mass of half that of the Earth and a radius of f0ml vkd*d z h.k94 ey7a;e2nltwice that of the Earth. What is the accdke*lyf mn 4e90d 7h;zk2va. leleration 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 ;dhaw(7*v t ;ixldrq +Earth. The radius of the Moon is one-fourth that of th l;;dxati( r* w7+hqvde Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the radiuyyl(5 30lph2gq;vmqm uodr+ 2 0kms2 /7jwhkps of planet A. If planet A has mass m, what is tw s3vldyjo7 ; 2(0 h5hqmrguklmm2pqy/2+ 0pkhe mass of planet B?

  Two planets have the same surface gravity,u du4ky;y9q9rt* q,0 nkl b1fb but planet B has twice the mass of planet A. q l 4yun 9db91fk ;k,0qruy*btIf planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about aatg-g5y7: ,pig 0u0p mkadz,g spherical planet (mass M). Which expres m05p0d p g,:7kgtugaiazy-g,sion gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite izc tcn07--wy B, and rotates in the same orbit. Compare the two sc z w7-0tn-iycatellite's speeds.

  A person is standing on a scale in an elev1 + hwp5w 91oyf+ q3jn:a myzdzwd:9yfator accelerating downward. Compare the reading on the scale to the w dam:+ y 9o fzy53ynw1dh9+zjf1:wpqperson's true weight.

  Who was the first person to real+o4q,rfd0 xxyize that the planets move in elliptical paths aroun4d,qr x0+ oyfxd the Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbiwz; b+qlehhw59e(;04tr dow ot around the Sun,ewqe oo+ 5zw l(rh b49h;0tdw;

  Let the average orbital radius of a planet be R. Let the orbital p0;q *ix+* 5hslmkatsf+m sf 5sw:m *nyeriod be T. What q5;+t5*s:xh s mm0il mn+s* safw*k yqfuantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the.m. /81 /m2qsekh. kwrsw.c(ep*d)ap jkgtpa galaxy Andromeda, with the same op a 2.8pj/wm (ahqe . )*kmsd r/1setkgwkc.p.rbital 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 (82cbxtyj .-:gw*afd a2 saty is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a cfad xg- y8w( b2sj.2*at :tyayear. What is the asteroid's average distance from the Sun?

State Kepler's laws.0e08mj+ cefau

  List the four fundamental forces in rs5e*z/tl/kdfv-z1ez fp ,t2 nature.

  An object moves with a constant speed of 30 m/s on a circular track of raean* l ;a inqc(sbn0;f4rxd*, dius 15saqbefn*id,ran(* x40 ;cl n;0 m. What is the acceleration of the object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximum sp3laj+4 k :os w8c 9yre6cvmd6weed around a curve with twice the radius? (Assume all other ycdvwr8wl 4c j9 +k:eso 6m3a6factors remain unchanged.)

  What is the centripetal acceleration of a point on the perisua1wejf19) y0d p;v qmeter of a bicycle wheel of diametvuq jw p);1fed 01ya9ser 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the axis. ptn3hny15i9kpatb6 6odwe 4 / What is the centripetniy p/bpth9 63ak5dwe6o1n t4al acceleration?

  How many revolutions per minute mustp9mg*y*z ry+gc9)c4nzqz 8ob a circular, rotating space station of radius 1000 m rotate to produce an artificial gravity ofyz*z 4bcq9)po*y8zr c+gm 9g n $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. 1zi k1g.zo9t v It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on z.gvkt o 1z1i9the motorcycle?

  A 0.50-kg mass is attached to the end of a +x +3vg/ yct55fr qlcl1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the ml v+g ytrcx5/3flc+5qaximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a stronggra6jh, v8-ve x:/uv+ 8ifncn string and whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times t h: 8xf nv-in,c8/ejv6r+g vauhe stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached t0sr hml*b4zn1z g )zz(o a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the 1rsl*bm0nz )zgz (h4 zstring 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 acceleration of 4g when pullh1//ofvdbuai,0 ffn3 ing out of the dive. What is the radius of curvature of the loop in which the plane is f f/h,nui1fao0dbf3 v/lying?

  A pilot makes an outside vertical loop (in which the center of the loop is benealq w,b5j6 mmv3th him) of r,vmlm5 36q wbjadius 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 going?

  The maximum force a pilot canq)p 6 nwg9z;m.xbcj4 r stand is about seven times his weight. What is the minimum radinz.c 9mb;qr 6wxp) gj4us of curvature that 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/a,j.d exg .tm1s rounds an 80-m radius 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 road sue xagj..mdt 1,rface.)

  A car is negotiating a flat curz -g+wqz0n26dhyuth.ve of radius 50 m with a speed of 20 m/s. The centr6du t20hghzzq -w +y.nipetal force provided by friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a wr985 dq gfup(flat curve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to make the turn?dur(8fw pqg5 9

  A car is moving with a constant speed v around a level curve. /z4vw a 5o g3dc2mzkl8 The coefficient of friction betweec/ 85do2v3z4lwa mzgk n 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. i6*0: 09 tcs.loltkl8jj ifk:xwnwr required for an Olympic bobsled to negotiate a 100i ls nwrxi.:.6kt09:* t 8ojlfwlck0j-m radius turn at 35 m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsjya6*y)(fvd v3x -qroled 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 radi++ ++;ice n2xbpebeqk 5l v4mjus 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank(iff5)s+idz fl u.g/y ed 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 revolving uniformly in a horizontalvf s9,u,4ubaq circle of radi avf suu,49qb,us 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 zk s3q:qx,gz/i *ff2kcl81geng 7(l m 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 blanq2 mq:xe (fcigf n ,7gkkzz 1g*ls3l/8ks)
(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 pre9st +:iz)8 vdyvzxq ip4l p59oton 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 gravitatic,z+pkpb x zz ,+hh:+vonal force on a 70-kg person standing on the Earth, due to the Moon? The mass of the Moo pbzp:c+h,x k+,vzz+hn 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 n7iq (cj-6*wuor+t/ mc2pmp g(v.td nmasses is F. If the masses are moved to half of the2 gttcmn(6p ju+*i 7-on.pqw(rdc/ mvir initial distance, what is the gravitational attractive force?

  For a spacecraft goi5 b)c maq7l8yung from the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth cancelm8u 5al7q)byc?
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 i3)y0/, p3bd;f ,z pt0 uifqr, jovlvqps $7.4 \times 10^{22} \; kg$ 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 Earroenm gk /43y:th equal to the radius of the Earth. What is her accele grm3:4y/onk eration due to gravity?

  The radius of the Earth is R. At what distance above the Earth'+tlxfehkj82y 9 2qqd8 s surface will the acceleration of graviyqt x8+qf9 2leh2kd8 jty be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 tiwk;uv.7a * 8 jp )xpqjuq52iqkmes the radius of Mars. The accelerati 2q;k juwp)ik7*x5ja8qvq u. pon of gravity 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 acceleration of graviv i*,rub+c nrj 5/xyd.ywr l/+ty ry5+rvl cw*du/+ijx.rn ,y/bis $32 \; m/s^2$. 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 haa3 (zz,upj7jgs 5k5 hms radius r. If the object is raised to a height of 3r above the Earth's surface, wh5zkjmazpgh sj(37u, 5at is its weight?

  By how many newtons does the weight of a 100-kg percpu.7spj* f3px;s c;json change when he goes from sea lef7s sjpc p3xj*;.puc ;vel to an altitude 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 100 kg is at a point 3r abovei/dxihfz7or4ya /w6k,j f(gf3b08 aw the Earth's surface. What is the satellite's weig3f4yg f0/ w8jkaw,7f 6xzdboh ira(i/ht?

  A spherically symmetrici 9w( rx amenyiou n +.r+nos:vwh82+; planet has four times the Earth's mass and twice its radius. If a jar of oni h:w8+ yrs2 (nm;inxe + o+urv9.awpeanut 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 Moon, Earth, and Sun 4ffvvl6 08 mjif9 v+j/vci0( vr:m4tooo m/sk all lie on the same line, with the Earth between the Moon and the Sun. The Mor:8/kfvvjt94c f6mv(omi0 0o /j4 f omv+ivlson 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 thej:ej6* wck/ij 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 Eartx lq50mfb;3s:c:x w phh (i.e., it just skims the surface of the Earth). What is the speed of the satell5x0:mfq3 hcw sxp:b l;ite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit 8hxktl( jsxo:u;0;7: gu cc vqabout the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Ea(o u0x:ctj qs: h vc;ukglx7;8rth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 23w0 d8)5qadt hkqmll,00 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of the Eartd)05lwqd l mkt8a0q,h h is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has a lal2 j-fi:nqz 92:waln 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 Jupiter orbits the planet w5s,xo /d5dt(;gnw8 9ip0x0apu aj (,xyzzgjwith 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 qn4xz/cvrv . hec9h 1/xzd*;l. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 2c4x;erh/1.ldx z h ncqvv9/ z*0 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter i6;auxcmds;:3 mj2q g es $7.78 \times 10^{11} \; m$ 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 is the average , hl nh s)5rr,tm/t2cadistance from Jupicanrhr 2t5m/st, ,hl) ter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)