Is it possible for an object moving with a constant:utt zf3c nqh: m -gvxk3-u:+g speed to accelerate? Explaimt :-cxugq-3+::gnhku3v zft n.

  Consider a particle moving with constant speed such that its acceleration o+8t nf4 hf:yipmxzs96f constant magnitude h6m8xfft:n y 9zpsi +4is always perpendicular to its velocity.

  An object moves in a circular paps yrd(d quz)*,+ mrs)th at a constant speed. Compare the direction of the object's velocity and accelerationryu* )dpq, (s)dzm sr+ vectors.

  When an object experiences uniform circular motio dy2.sedg)dp2flrt 7ihpn-5 2n, the direction of the acceleration i 27spid5nret2.hdyf)2dpl -g s

  Consider a particle moving with constant speed such that its accekqt40sb1soeuv/pb 5u b. 0c0nw hs ml1pq1t;;leration of constant magnitude is always perpendipe00qbhl;1buk4 .pqv nbt1t woums1;5s 0cs /cular to its velocity.

  What type of acceleration d8)y.sw kiwbx pt(+gg k1 l9p1c,x ul0qoes an object moving with constant speed in a circular path experience?c9qu)x8pg w+kt1l ikl1y p( bgxs,.0w

  What force is neededm2onp hrg2 w15 to make an object move in a circle?

  When an object experience+wal4 -qo qxw.s uniform circular motion, the direction of the net for+aqwxwl.oq -4ce is

  A roller coaster car is on a track that forms a circular loop in the verticqz-sfcqw,/4oc/ h)qg j5r /hhal planejcc-,)q s/ hh5z/ rfwghq 4/qo. If the car is to just maintain 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 (6zvom r ot4br5as)e5g;uc 0c = M) is on a track that forms a circular loop (radius = r) in the vertical plane. If the car is to just maintain contact with the track at the to z;s4tr ucragv5eo0c b6mo (5)p of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circuljv2cx29+omw +2tpfaq n* fqj 5ar arc until it is going straight up. Just as the plane is at its lowest point, the force o25njp+22qj+oxv a tmqc9w f* fn 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 o*gr pw0mfo19 jf 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 constant speed v. The;0vc9fl28o7hb8 bc j t6ph kann it goes around the same curve at half of the original speed. What isfcvhpb82kn697 l;0at ohb8jc 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 igi w dm cx35;0pmh9;f5-wvkqspeed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it g 0i fhm d;wk9 i;gx3-cqmp55wvoes around the second curve, compared to the first?

  A car of mass m goes arodmf 7k,+ .y*i)6 st6xbzadu ;dn :qoguund a banked curve of radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component ofdb)gs x6,uufa zm;k+ od y6in :7d.*qt 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, but onr enjh9 k-(-oppmfs20 e has twice the radppnom-f0k 92 rh(sej-ius 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 larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constaejb 4 ta8w;bd2nt, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming oe8b 2wjtd 4b;aut of the turn. Why do they do this?

  Is it possible for an object92hvcses4 0j5nog2)e,p zqup moving around a circular path to have both centripetvhns2z4p0,2uc p 5joe9se) gqal and tangential acceleration?

  The gravitational force between two objects is proportionaq+ 4wo:g7db jol to

  The gravitational force between two ou(8h llg *mz:vbjects is inversely proportional to

  Two objects attract eachl27 2 dp jv8y(8mkjfks other gravitationally. If the distance between their centers is cut in half, the grav8kkv (jsf ydljp78m22 itational force

  Two objects, with masses2*k.9cplhgmr h8hv7m( n x3hy $m_{1}$ 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 mass;ig -x5gi4fir es $m_{1}$ 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 grav -5l s4p.oddnixo.- d 1tbx(k0j vqhn2itation.

  Compared to its mass on the Earth, the mass of an object t4n 4+9nj1ehfet8itxo7 ka z;on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it is on Ear5vm*l a7(:5emwxco o ) )aesdpth. An objmwx)*:5 osld)( aocm5vpe ea 7ect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from tw2w;+ee ;elg uhe Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. wfu65zucwx* hlt, n)1At what point is it beyond the pull of Earth's gr*f,)wu zhx5uln 1 ct6wavity?

  Suppose a satellite were orbiting the Earth just :yd 66 psos+lzabove the surface. What is its centr6z+s:sdlo p6 yipetal acceleration?

  A hypothetical planet has a mass of hal4.g wily9pt -jf that of the Earth and a radius of twice that.-g4ptl9 jy wi 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 gravi1 /rd;zi knd 0b-sp)uvty on the Moon is one-sixth what it is on Earth. The radius of the Moozd /;ks-nbid )0p uv1rn is one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surno) tn8l.e t*xface gravity, but planet B has twice the radius of planet A. If planet A has mass8x.tnn )*te ol m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B has tw.*:+as vkp.8zqup;oolp 4iub ice the mass of pl+ip:. sp oo. ba;pqklu*z4vu8anet A. If planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius fp kc3* knkmec.tllix 42g:.6r) about a spherical planet (mass M). Which expression give. :2 im k .pklg*n3c4fexk6clts this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the samr5jm-f8x3r lj e orbit. Compare thr- 8 jrfl35jmxe two satellite's speeds.

  A person is standing on a scale in an1bgfbf+w ;fr3oi:z+ mzmx y/+ elevator accelerating downward. Compare the reading on the scale to the persfim 3oz f+rw;g/b yzb+1mx :+fon's true weight.

  Who was the first person tolnupaj31s7qvuyx;j s 8. cy4 + realize that the planets move in elliptical paths around the S 1aj7xs cnuql4y;spujv8 . 3y+un?

  The speed of Halley's Comet, while traveling in its ell,jgk-rf /tv4d iptical orbit around the jf, -t/kgvdr 4Sun,

  Let the average orbital g9+.l0k fxmxiradius of a planet be R. Let the orbital period be T. What i0.gxfl k x9m+quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a stnpfiq hb7y32zl kw(2:ar in 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 of revolutiofw in2ly( 2ph b:73zkqn of that new planet be, compared to the Earth's orbital period?

  The average distance(cs /z z/ry3tn from the Earth to the Sun is defined as one "astronomical unit" (AU). Ar c zy(/tzs/3nn asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.gyqfd7 -e5 ,jm

  List the four fundamenzoq8 v p)vt-2ttal forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radiu0d(9q n 49km ph pr(q(bbkr9tgxy w.1qs 150 m. What is the acceleration of thehmnbtg4q1(k0 prwx( qpd(9r99 qk.yb object?

  The maximum speed around a level curve is 30.0 km/h. lq-4i1woyk:tdg1zjm1oj01k What is the maximum speed around a curve with twice the radius? (Assume all other facjg1y1-odt11q ikkm wjoz04l:tors remain unchanged.)

  What is the centripetal acceleration of a point on the perime t+zx-,w p5m6vwcjf +mter of a bicycle wheel of diameter m6pv+cw+mxw5-,zj f t 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 a4r 5in*/pz cxm2 oqs4oxis. What isio5sx 4nzp4c/rmo2 *q the centripetal acceleration?

  How many revolutions per minute must a circular, rotatftd2z7 q:ar1 pi9yf- ving space station of radius 1000 m rotate to produce an artificial2q:17 ztvyia-rf p9df gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 *s3v yydz vti-;p8gs 6 fyg6ugj.1a4xkg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centrgyga6xv s .; 6jtyvdsf8pi- z3gu1*y4 ipetal force on the motorcycle?

  A 0.50-kg mass is attacu-r( :ew8h0 gq hfaw3bhed to the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is30 h-f ar (ughwq8wb:e the maximum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a str7vt/ukn bl4kvi . ob88 v3c pequj:5;dong 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 the stone's weight. The stone's speed at this poi:37nl8 ci.tv;5ukb/d k ojv 8eqbv pu4nt is given by

  A stone, of mass m, is attached to a mbx0w 7j;taq5 jtw2h8 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 stone's speed at this p j8atwb xhw7 t2q0;5jmoint is given by

  A jet plane flying 600 m/s experiences an acceleration of 1eo1f yq)z2rq+ dk7lk 4g when pulling out of the dive. What is the radiu2ezdq ry7 1kl+fokq)1s of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the v,ddrt jzsy8b8-so h0, 66uxbcenter of the loop is beneath him) of radius 3200 m. At the top of his loop he is vbst0h ujd yo-bx86zs,r,6d8pushing 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. What imc8gly3 u gnr:4cbo3 k ,h+ed*3o ulj0s the minimum radius of curvature that a jet plane' mcc3ud,r o+ 083knyj*ulg 3lob4gh: es pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rou:*7nnzv te uf8-fdd g4nds an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radi:ent dfu7fn4dvg8 -*zus 320 m? (Assume the same coefficient of friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a speed ofii3 dl.1u;yf* mrb-tw 20 m/s. The centripetal force provided by wr. dtuy; f1il* im3-bfriction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve oupn9k hxxh.+/ f radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction betwe9ukh/ n h.+xxpen the tires and the road for the car to make the turn?

  A car is moving with a constant -pfjgzz*cby /i/w 5n.speed v around a level curve. The coefficient of friction between the tires and the roabjw/zyf.i5 cnp/z- g*d is 0.40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle 2 +;ddbcgdyq0wjja1x x;4rc3 is required for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s wi4ag0j;rd1d c2j3;x+q xdc bywthout skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is bank 03 eub7(,.m,wycj m/feiqjvh znv09u ed 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 e eiigll,jw 21*4(f6 k x;slbkat an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 *i4xfc)zj t:hm is banked 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 cirnq/i9cn zdja4/7xv) q cle of radiusaqvd7 4/9j)z cxin/nq 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 tm7ad9wv-d b )g0os;bto a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical 0-v bgd7m;)ad9s tbwovalue 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 prorkk,8us0o r .qy4yl ;kh) .nsuton 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 fjvly,g9 .5lfsw ).d*i gs.j tperson standing on the Earth, due to the Moon? The mass of the Moon t )fll9fgd .jig.s .j5*wy,vs is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force betwet.ck et /fg0;us y-ti)en two masses is F. If the masses are moved to half of their initial distance, what is thuc./ 0;s etk-ygfitt) e gravitational attractive force?

  For a spacecraft going from the Earth toward ur ol/l333nkothe Sun, at what distance from the E3ulr33/ oko nlarth will the gravitational 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 is sa wdyon; fvmx(,:p*hp83m.s $7.4 \times 10^{22} \; kg$ 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 o ;bh*uis k6pc o0t ;z6fgh,b-a "space-walk" at a distance above the Earth equal to the radius of tuphh *6-fk oc;g6st0bibo; z, he Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surface will t(,aw2q 1lwxw hhe accelera 2w1x, wa(whlqtion of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface eh.hv; ;qsp* kptgg0z3qual to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity onh vqgg0h3 tszpkp .;*; the surface of Mars, is

  At a distance of 14000 km from some planet's center, f+cf;8 nqd)lfkv :5snng3va7 the acceleration of gravity fn g lvnk 3c5d;8+7n)fsqf:v ais $32 \; m/s^2$. 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 hb.e n byln;y,*b n/6kr. If the object is raised to a he; , k bnybnhbey*l6./night of 3r above the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when he goes frrp++0flg k:f1 pb(eyg om sea level to an altitude of 5000 m? (The mean radius o+fggr(b0k e+l pf yp:1f the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satel,u l9g -r cnn4p(f4kww0xc lr 5cw9ug/lite of mass 100 kg is at a point 3r above the Earth's surface. Whal5 r-cn/rlcx4( uwnfw c,pg99g40wk ut is the satellite's weight?

  A spherically symmetric planet has four tiekafe34b80q 5;4ut(asi- ; d lbie x bsj5/ncemes 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 weighceib jqtie 50/4d 4e-bfn(e8lu ;5 aa sksxb;3 on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun k; 8bdhjry2y6all lie on the same line, with the Earth between the Moon and the Sun. T8rbjykyd;6 h2he 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 transc.0itmtl,6hm ported 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 orbit about the Earth (i.e)vl12i e0 fe ;ln(3rev hk8hq.o(puh,cq qe9f., it just skims the surface of the Earth));q 0k(r8h13p iovlfel, qu(vhq9eh.2 eec fn. What is the 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. 8iyz tzul2+a;e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth? l8;a u tzzyi+2(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 the Earthmd7 6tchct/6p- j3duxqxb 6pzo uu-84. It is observed to have a period of 89 min.87dxp3zd 46j/tqubx m htpuc6ocu6- - What is the mass of the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital lekr z24j9k d ti..l0jhbrk 42diameter of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Ju5k)ni7jpn + rzpiter orbits 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 ne(:6x6y *ylg6l iu85 qex zijacarly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbc yj56*ixqy(u 6 :glxzea 8l6iit. How long does it take moon B to complete an orbit?

  The planet Jupiter irx)jxn)d4, jq 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 tr- v1qwyee)v.o orbit the Sun once. What is the average distance from Jupiter 1y.e)vevq- wr to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)