Is it possible for an object moving with a constant speed to accelen66ujuf8 q +etrate? Explain.q6nu e6 ftju8+

  Consider a particle movijzvp8n8qh r*/k rb7 6sng with constant speed such that its acceleration of constant magnitude is always perpendic7qkrrh86*8jsz/ bpnv ular to its velocity.

  An object moves in a circular path at a constant speed. Compare the direction orbe0dhn ofk/1w6ye - 0f the obor1nye60 kfd-w e/b0hject's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the acceqk13w8b4k gx klerwb3q x1k4k kg8ation is

  Consider a particle moving with constant speed such that its acceleration of,ktbg :xm/fuwc q-30o constant magnitude is always perpendicularwxf cq0 um:,3b/ -gokt to its velocity.

  What type of acceleration does an object moving with constant speed inppx-vb )63f p/g t5rimnq6/ta a circular path experience?x-mfbp3 //t qg5 )p6vtnrp6i a

  What force is needed to make an ob.xe2ujy8ekt vomnvi4 y6* b2t/q ,uy4ject move in a circle?

  When an object experiences uniform circular d hfivg mo+ a+df lm;,83hxu/3motion, the direction of the net forcmx3/lha+m3f+ dh d;,uogvi 8fe is

  A roller coaster car is on a track that foreuwm7 b3eic9 /ms a circular loop in the vertical plane. If the car is to just maintain contact with t w7ee9mu c/ib3rack 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 kw iba /1 7uef/zccaxy(9r;sfe0 3p s2track 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 value for its speedz2ewu; sif1rs/f 93ac(yapx 0/7ek c b at that point?

  A pilot executes a vertical dive then fo* ,lu qo4 7,6ipodpezsllows a semi-circular arc until it is going straight up. Just as the plane is at itslqz p,*eo6o ud7ip,4 s 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 rad5)o1 v)e daufp4u4iloius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve ofr+ryvju5,sk qe:.4gah ,(zcj radius 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 to the first s+jge 5r.(khcza r4,vu,j:q y time?

  A car goes around a curve of radius r at a constant speed v. Thf1z46npd2fzcus6ak/0 0 aqj uen it goes around a curve of radius 2r at speef 6a0 p/jfads4n1z2kucuz0 q6d 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 radius r with speed v. If y.j j;yg b:tb.the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from ttbjjy. b.:y; ghe road is equal in magnitude to

  Two horizontal curves on a bobsled runvi7ezc; pu;a4t1kpj;dj; /xn 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)7p1e;v pz4xiajckut ; ;d n;/j 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 tramct2 oaoek.hp,(*t m-x3m c7yck is not constant, but increases upward from the horizontal. Coming arounox . c(pmm7mt-h oyt,2a*3kced 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 objetk.to*+wv 3kxxf 02 hqct moving around a circular path to have both centripetakxktv.fh qw0x*o+23tl and tangential acceleration?

  The gravitational force between two objects is proportional t5 yjp3:u3v3qbi e h0rlo

  The gravitational force between two objects is inversely,c af-ad s5r9g proportional to

  Two objects attract each otherx myre v8+1e(z gravitationally. If the distance between their centers is cut in half, the gvm+y (xr8z1e eravitational force

  Two objects, with massewbivd r2t- v*0tn w9z9;o /dejqiu 5u9s $m_{1}$ 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 wp3l 7nu na1(fvs-w- -lu +fvh$m_{1}$ 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 universal gravitdkd//d1e 8a w25itbaglnw/n ql x+50tation.

  Compared to its mass on the Earth, the mass of an objecei1 w;akki3 0st on the Moon is

  The acceleration of gravity on the Moon.z1;zxk 7z ka;by,xyw is one-sixth what it is on Earth. An object a; yzkx1 x zy,.bzkw7;of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away frunzd6px-;i8b4) zkl/ob dc3h jm 9u)yom the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull ofq8kf wjei)g jl(f/m2 v5sn: 5z Earth's wgmi)vj5 zf5: j2 (snekql f8/gravity?

  Suppose a satellite 7mjtk9g lj9z )y20j3, fdepv swere orbiting the Earth just above the surface. What is its centripm9 9e f0p ,ktvj)dgzj 2lj7ys3etal acceleration?

  A hypothetical planet has a mak-vi2a9 qr pwbn+qigju 4 6y-6ss of half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms46qjbgynr6kau -i w-2+iq p9v of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Ea162hcm; xghpe rth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass comp2h mce6hxg; p1ared to the Earth's?

  Two planets have the same surface +f2rnq)n(t/m-knd iq gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of q )t+drm -n2nnqi f/k(planet B?

  Two planets have the same surface gru8a rqi(evt 8 q-07 j-b;xgproavity, but planet B has twice the mass of planet A. If planet A has radiurg0 8eu-brao tij-;78qq pv(xs r, what is the radius of planet B?

  Consider a small satellite q; s8ae)kvo;h 8j)swbmoving in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbitalja8 ;;)skbo hvse)wq8 velocity?

  Satellite A has twice the mass of satellite B, and rotates in thm edn. ,ifdd0z5hot8 9e same orbit. C t,ido.e8fn059 dzd mhompare the two satellite's speeds.

  A person is standing on a scale in an elevator accelerxiwt*hwl ;00 eating downward. Compare th iwxw0l0e;* hte reading on the scale to the person's true weight.

  Who was the first personntk1xhlq d: y,8 f,9jz to realize that the planets move in elliptical paths around the ,,flqh x8nyk tdzj1:9 Sun?

  The speed of Halley's Comet, while traveling in its elliptp 4c,k p 6cl+ymnvar,y0rv5m 3ical orbit around the Su,6mm04 n cvcak rppl+5yr3v,yn,

  Let the average orbital radius of a planet be R. Let the orbital pem pzw a+cx53r12p34zz k3xs jgriod be T. What quantity is constant for all planets orbiting th zrmwc1zaks+2gp3 343jxxp z5e Sun?

  A planet is discovered to orbit around a star in tho h5q mifywa:z:g )z7rowwqy/7.v9+we galaxy Andromeda, with the same orbital diameter as the 7yh5 wqm y:oifr:) z9 ozwg.wawq/ +7vEarth 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 "astronoms0zi/ v7 dr (dxhw2/rqical unit" (AU). An asteroid orbits the Sun in one-third of a year. Whax hvdiqr(s/d2 0/z rw7t is the asteroid's average distance from the Sun?

State Kepler's laws.s4)l:xv 5ix2(rle*thriq ;ec

  List the four fundamental f .pmvvzy c,0(lorces in nature.

  An object moves with a constant s0fvh .5 tp6baapeed of 30 m/s on a circular track of radius 150 m. What 6taf .ap 50bhvis the acceleration of the object?

  The maximum speed around a level curve is 30.0f67abgw vz:sv)8 wx8 p km/h. What is the maximum speed a6fxwv )spz 8b8 :wv7garound a curve with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on the pd*m: b*dejc l0o f0k.cerimeter of a bicycle wheel of diameter 70 cm when the bike is movingcj** cm:fk dlbod0.0e 8.0 m/s?

  A point on a wheel rotating at 5.x fys.qo j:kuk-b2k9 d//p9a7 t2 nunj00 rev/s is located 0.200 m from the axis. What is the cfp/9 :yjj7tq 9- .2ksxn k2dubkaun/ oentripetal acceleration?

  How many revolutions per minute must a circular, rtm 8bn,rfg9ho5w;1l lotating space station of radius 1000 m rotate to producef5h w1lo;rmgb l9t n,8 an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes pb9p e ktm)pdtre80*)jmg e +x;bmj 7/around a 13.7 m radius turn at 96.5 km/h. What itp p/em0ekrtm;8 7xj9b e )*mj d+pbg)s the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the e)0 d w 3bl ejazq*7qzjw4i:fa7nd of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tensionef:7)3q 7 wz4b0qa jwzaij*dl 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 string and whirled i7 7ehr 819wfn vo ns.+emelle1n a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone'sen+9or7sll7m11e nw8f . veeh weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a mgu(;c;6v wcf iox )qii;p1zt axwhx-)18+mvstrong 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 stone's speed at thi1)o(w;qf m+wpxi 1h;z caicmivu gxv-x; 8)6 ts point is given by

  A jet plane flying 600 m/s experiences an acceleratio,u:un;o gfwh vw168nzn of 4g when pulling out of the dive. What is the radius of curvature of the loop in which thvfnw n;uo1:w 6h, 8gzue plane is flying?

  A pilot makes an outside verti9x;i8l(j*ig 0hk uv kncal loop (in which the center of the loop is beneath him) of radius * xuvl; ni9kk8gji(0h3200 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 can stand is about seven times his weight. u4-x* foduwru wf dtf,lt qxq:+2/a01What is the minimum radius of curvature that a jet plane's pil*d f1:0twqqtuu ul2,wd xfo-x+4 raf/ ot, 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 +;(3smvp:7j)nzo 4h40dssofgw ts fh horizontal curve with the tires on the verge of slipping. How fast can this car round a 7 h(g s+fw3n);sv:h zso4psofm dt0j4second 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 c )ax 2zoyx*.rowe hd0 ov6yk6-urve of radius 50 m with a speed of 20 m/s. The centripetal force provided by friction iokd2 r a.*zyx6oh wy-v6) oex0s $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 50 m a oz 2mq bely ,o67/ydozh),ytdr+)x1z3h gph2t a speed of 14 m/s. What must be the minimum coefficient of fri),3o7h)lzy +dd6hz 12teox,m r yg zp2bq/ohyction between the tires and the road for the car to make the turn?

  A car is moving with a constant speedmj/f)t dvo 2o6uxuu81 v around 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 u6t dm8x2oouf / v1)ujstay on the road?

  What minimum banking angle is required for an Olympic bobsled to negotiate a,2,wa-bgbt mk )l odmf*3x j6o 100-m radius turn at 35 m/s without skidding? (I xa,d)m2mfob 3t *j o6kgw,l-bgnore friction.)

  A horizontal curve on a bobsled c aod94 f;kk,trun 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 anglo8 afhg bg0merm0:jlg n8 ,6y7e of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank3in.9gpaq lylrm 3 .hpy 9gw(7hr-nia b1e2+ fed 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 horizontal gwr s33j.ttjo.q kzw+w18-en circle of radius t1kne..t osq8w3j+ zjr3wgw-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 unifolnyw0w6*bzt)v siefv,,u 1 yz,y)93o wdg 7r mrm rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical valu wy1w,by9zdse vug,lw*67i3r, )mnt fv )o z0ye 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 f)w)ypl+w orx/az( ,vk o,t 7xof 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 standing9 ks hdtgy7 g*y)t9e rk-9*pocw2ypd8 on the Earth, due to the Moon? The mass ofgsh- kct*ed78*2y9yw9k 9p pogd) yrt 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 masses ar1 s4x 3uswurr3pg8fq.-jfu*b e moved to half of their initial distance, what is the g3-fr 1s8 qr jupb* gu43w.usxfravitational attractive force?

  For a spacecraft going from the Earth toward thjw c 21xskl1-* ng(eite Sun, at what distance from the Earth will the grav1j w - 1gcikt*lx(e2nsitational 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 iv-qe l0f- -uhis $7.4 \times 10^{22} \; kg$ 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 Earth e0)yus,x 0 ,up2q 87b) rzqjn0u ;ler7apctnoequal to the radius of the Earth. What is her acceleration due to gravituq,rutx)lq o 2e; 0b0pe u ,s)rp7nazc 7j08yny?

  The radius of the Earth is R. At what distwg 7/c u1*gudyance above the Earth's surface will the ac/y1du u 7cwg*gceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above itsfw1fi;osj/1enf9vjb6vk *z65 f 3vmv surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration *svn369o wfb6v1vj;fi kmef5 v/jf1zof gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, b*2zma p::am ithe acceleration of gravity is b:2 *iaapm :zm$32 \; m/s^2$. 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 rados19e3jvhy 0 yius r. If the objeys01h3v j9y oect is raised to a height of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person chah98;xqp pvnm9ma.- ki nge when he goes from sea level to an altitude of 5000 m? (The p8 -nm;99. aq pkmvixhmean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite * 8:lbe. rrzee2g2xtzof mass 100 kg is at a point 3r above the Earth's surface. Wha2e.:be e 8lrzg* x2zrtt is the satellite's weight?

  A spherically symmetric planet hashwocle r,:f*fk(s,21 y.d uiy four times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the yrufd.sh: ki21fl , (eyw *,ocsurface of this planet?

  During a lunar eclipse, the Moon, Earh afds d*(+7 d,kgp;y.m6aaw kth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. aa6p( m;kg,+kdhwfyd. d7s *a 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 th : 2c,qbg:kn u9rrxza)lg6vh7c 01rpze 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., w1iqg6n4.yhk 2s :neu a.dh5g it just skims the surface of the Earth). What is the speed of the satellite? (The mean gnhy1sk2ua4:5h6.d ig e nwq .radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low 3v hvewj/i,- n*: agx. :rnmmrcircular 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 r*hw ni3:g n ev vm-x/:.rjam,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 Ead1qcpry4ym1 l/jc :s3rth. It is observed to4djp/ lym 1qrs3c 1c:y have a period of 89 min. What is the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiterdwv/ sy,i r6, pm-h*fu) 4m jtqpcn*8l, has an 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/ qbfx+kxn(:w 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 orbi:i*s9ye f ebgfm50m- qts. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to cqg:m05b -*e f9miysf eomplete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter ieq;d g6n4 0:nhhtiw1 n30lqqo s $7.78 \times 10^{11} \; m$ 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 orb3; .u :tok; /qeisynr+sl3u (q44rsjdrngp p,it the Sun once. What is the average distance from Jupiter to the Sun? (The distance from theq;u (yjd.n;/3prkpr +leoss ir 3ut4 ,q4s:ng Earth to the Sun is $1.5 \times 10^{11} \; m$.)