Is it possible for an object moving with a constant speed to accelerateb1z c-mt3ene z+de d tp, wor8-fo;0*e? Explaineo-zw1 d3f+cb*e ot zt8,;nderpe0m-.

  Consider a particle moving wilbgw6jx- 81wl th constant speed such that its acceleration of constant magnitude is always perpendicular to its velocw8-bll wj6 1gxity.

  An object moves in a circular path at a constant speed. Comi wuc+q1nx );mpare the direction of the object's velocity and acceleratioq+wc1;ixum )n n vectors.

  When an object experiences uniform circular motion, the direction of the ac9mg+sfuv,qsiqy(;o d) 50iqr celerat i9+ ,o (iuvdqs0)mgqs5fryq ;ion is

  Consider a particle moving with constant sp z;*(r6yod szwqmb+6reed such that its acceleration of constant magnitude is ar zs+6 bwrq*y(6ozmd ;lways perpendicular to its velocity.

  What type of acceleration does wwl/*bwuo(d-my jtt--8:i dw ,4z tkp an object moving with constant speed in a circular path ed, zpjub:ym4kt w t--w/ido* 8 t(lw-wxperience?

  What force is needed to maloni;4y1 .xwv ke an object move in a circle?

  When an object experiences uniform circular motion1n 3 8 -;hrgy7ipayr+r*vnapz vrqr9*, the direction of the net forc*3z1vr*nr9r + n8v7- ayh pagpyi;q rre is

  A roller coaster car is onatvx b ,mh0+kqy5r*+v a track that forms a circular loop in the vertical plane. If the car is t0+kmbh x*yvvqta5,r+ o 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 = M) is on a track that forms a circut:wg54zba75id 4 wjuular 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 th:b4j7u auw z55gtw4i de minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc*5i9fnbt -foa9 -u tad until it is going strit -n9*95oaf- tf dbuaaight 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 2qbj9 kz iafm4ib;ae 2qu2:z: 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;:twj o2 ez.dn speed v. Then it goes around the same curve at half of the original speed. e d .nw;:jt2ozWhat 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 curve of radius r at a constant1dc:hpvw;o; b.k d-) 2wkjdln speed v. Then it goes around a curve of radius 2r:1kk vowh2l; dn)jdd .pbwc;- at speed 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 arounda9gcb6rm(o4 v a banked curve of radius r with speed v. If the road or c(am6vg4b9 is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to

  Two horizontal curves,d-3tgajrq6w on a bobsled run are banked at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to staydqr- t,w6 gja3 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 trac:+be phen+wqx5mndb- ;j/ ee 7k is not constant, but increases ;nq 7h epbb+j/we 5+ex-n :demupward from the horizontal. 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 circn; tq5f)1rz/lnx zih1ular path to have both centripetal and tangential accexz/n5)n z11l fi;rthq leration?

  The gravitational force between two obq;.r(zvcts 8h*bi;w pjects is proportional to

  The gravitational force between two objects i/ gtozak8;2t4tm ar 4oc1gu1ls inversely proportional to

  Two objects attract each other gravitationally. If 3 69fdb0ywwf+ q,yp asthe distance between their centerwaw y+yfpq0,b3df 6s9s is cut in half, the gravitational force

  Two objects, with massc.j;;mp wd vr7es $m_{1}$ 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 masjs38wjtl8 *hq5vcy yw3 zeb5 *ses $m_{1}$ 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 unic-t) i: euq;xylyknzmo ;o: uyw.:)4rversal gravitation.

  Compared to its mass on thejtv1i4m3p x a g *zg0b;ox9pv* Earth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth whaoizq s4 0z8mxh6rb79qt it is on Earth. An object of m0xo4qbs8 z 6izh9mrq7 ass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sur.-bwqi uv1ul7 face, the rocket's weight

  A spaceship is traveling to the Moon. At what point isvktdl4 yt(o8h ff. 7.j it beyond the pull of Earth'k7(v 4 t.yo.ff8h jdlts gravity?

  Suppose a satellite were orbiting thewm f(..* s9v,gmwwx8 azjmu: 1 sxjkl9 Earth just above the surface. What is its centripetalj* jxkzsw gawx91 : (.9s u,m.mvwlfm8 acceleration?

  A hypothetical planet has a mass of halsg6dmb0 3uk ; x/n)piyf that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on thd )xu p si/ykgnb3m;60e planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity onxl4 os +j6*b m-s6pygm the Moon is one-sixth what it is on Earth. The radius of the Moon is ool sy4* pg+jbxmm66- sne-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have theq c44 *im u4fgas.y3:l4lb7kqiie: xq same surface gravity, but planet B has twice the radius of planet A. ky3i bq.f *44 aic4umxseg l7lq i:4:q 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 the mass of / mfe6 2-azkpa3j ya3wplanet A. If planet A has radius r, what is the radius of planetekafmzp / 3aw3y-j6a2 B?

  Consider a small satellite movingxdqhe4d zanw,;se)59*q ,vlg/b*fe ff t5jo / in a circular orbit (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbital veloci,fbseflh/j9 v/5 )d aeg;w4zoqx,n*eq *tfd 5ty?

  Satellite A has twice the 3wb4)ccwn oh*mass of satellite B, and rotates in the same orbit. Compare the two 4 3ow*wc cnbh)satellite's speeds.

  A person is standing on a scale in an elevator accelerating downward.z0af :z2 rl:tj Compare the reading r l2:f :z0zajton the scale to the person's true weight.

  Who was the first person to realize that the planets move in elliptical paths a,tt3 +bprv q-aroun+3rpv-bqat t ,d the Sun?

  The speed of Halley's Comet, w 5:r:vq/ oxs:zqriinl4y( 40crjoh 5fhile traveling in its elliptical orbit around the Sunc 45o orxqz(ijn:/ rsy0f:vi 4r hq:l5,

  Let the average orbital radius of a pl(n0po l5y5hplanet be R. Let the orbital period be T. What quantity is constant for all ply55 no( l0hpplanets orbiting the Sun?

  A planet is discovered to orbit around a star in the galaxy Andromedazqe+eltt /*h 6, 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 revolution of that new planet be, compared to the Earth's orbital ph6+qet *l tez/eriod?

  The average distance from the Earth to the Sun is dk g x8r:7az aey+92jllefined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the aszaj8gk2 ley9 +xal r7:teroid's average distance from the Sun?

State Kepler's laws. m2 ;i):k h:lb5 wp155oq+ gtomndzfhz

  List the four fundamental forces,,byn-n tmja 8 in nature.

  An object moves with a constant speed of 30 m/s on a circulay,u(k nu o9+mzr track of radius 150 m. What is the acceleration muk(yn z+9u,o of the object?

  The maximum speed around a level curve is 30.0 km/h. What ip hqzqd0w2mh6 g57g4 0hx7tyr s the maximum speed around a curve with twice the radius? (Assume all other factors re0p tr7g24 y0657hqhqx mdwgzhmain unchanged.)

  What is the centripetal acceleration of a pointlticvbe14 ,c)9amw s+l/jl/p zpar 90 on the perimeter of a bicycle wheel of diame e, z rtcpliv40wc/jllb9m/a)+a19s pter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating a,vtp/h 8yo:f 5p1eyzut 5.00 rev/s is located 0.200 m from the axis. What is the centripet tpufvh py:ez8/,5yo 1al acceleration?

  How many revolutions per minute must a circular, rotating s63j 2x9seuha y jt8kw 70n*ccppace station of radius 1000 m rotate to produce an arti s6kjycj *2u cp8nawh7e39xt 0ficial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m-bmwcb/cwn;l -ln96 o radius turn at 96.5 bllno n 9;-6cbcw -mw/km/h. What is the centripetal force on the motorcycle?

  A 0.50-kg mass is attak/4vu ;gppo6mc 3fr b7ched 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 is the maximum speed of the mass if the string is not tofm6 ckp7/ 4ogu3;vb rp break?

  A stone, of mass m, is attached to a strong string and wf9h; ox hnk:zx2cgw:8 hirled 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 wex;:kx 2hw co9zfg8hn :ight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong string and whirled in a vertical a;wtcfq4q kn+w;6e (d circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. 4w(;6 knqc;qwaf ted +The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of 4g when p t rogb5hj9mb*m -rn) l 6)zje/f;f8hnulling out of the dive. What is the radius of curvature of the loop in which the plane is fl )m5 69hhr ;rlzmn*fe-jb bo8 g/)jftnying?

  A pilot makes an outside vertical loop (in which the cent)4pwryw y*o1)5y iqvber of the loop is beneath him) of radius 3200 m. At t 1)i*5pyvb o4r yyww)qhe 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. What is thym(mn sj9lgb *l, 6vjk o.m:u7e minimum radius of curvature that a jet plane'skm,m l sbo9y(jvnul: j6 *.m7g 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 cas (/ewgh;1p/ruu rv5urve with the tires on the verge of slipping. How fast can this car round a second curve of rauvr( ;5/ asg1 per/whudius 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 zd6bj bn29xi:a speed of 20 m/s. The centripetal force provided b:jbnbz 29xi6d y friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curv/z df9q,1 4go /uptcfee of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between thez 1gfpt , /f4uceo/9qd tires and the road for the car to make the turn?

  A car is moving with a c/ j ackp j;kho3 9,uez+h/ga+6d/vevhonstant speed v around a level curve. The coefficient of friction between the tires and the road is 0.40. What is the mi+3v9aj/ ok,jc d; h vpuz+e /6gahkh/enimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsh8v,0z tc eo8ajoed7v,rj44z ( s*o xdled to negotiate a 100-m radius turn at 35 m/s without s jezo h4(d,4sjr7x8a,d 8 czo0* evotvkidding? (Ignore friction.)

  A horizontal curve on a bobsled ru )rl h;3g-k3o01usvs :bwawlgn 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, p,wc *jp9:g/ kifk8 upbanked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is b s l44)ef fs1;gbuhzx6anked 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 bwtdgu6i 6(rmfig2wt.74 t6v string is revolving uniformly in a horizontal circle of radius 0.500 fg6id6 wm62v i.wgrttu4t(b7
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 accele npj*n8e6ksv* 0(qbrua mza62rates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in k s* j(e6p2z qvma8n*a60n burnumerical value 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 consistulay1 o)z b6ve:8 9fl6hxnse.b7c wh)s of a proton 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-xfz4z 5t/h0tcz+mbf aq*: t/pkg person standing on the Earth, due to thet//a xfpt 5f*cz t+0zzq4 mhb: 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 the masses /( ,hti9k wc s)dbo u)/z+7)hte qilxxare moved to half of their initial distance, what is the gravi7)xs/ z+w )iq/tek d(o ,)xlhchtbiu9 tational attractive force?

  For a spacecraft going from the Earth toward the Sun, at ww:a*(nhjji q aa*5- (z a9ycvxhat distance from the Earth will the gravitational forces due to the Su a-n:(c5 j x *(waj*hiaqyv9azn 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 nj frb:kejz .0g4 ,jn: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 distance abovejjkr8iuq;2x - the Earth equal to the radius of the Eaq kjrx8;u2-jirth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's surfa6u - k-1azp 2 t0ys-zmcf0ionsce will the accu 6mst-p -f-z2 zn0ao0i1yk sceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at hvvbp 2.,8j lazr3:d dabbb zl: f+;z.a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as co ,bj.vzblbl f;bdzda:zh 3 8p+arv 2.:mpared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, thek +w(fqqj( c/r acceleration of gravity ikcq/+rqf(w j (s $32 \; m/s^2$. 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 Eaiy4fsmh mn-)y/oy( 1nrth. The Earth has radius r. If the object io-s)ynh4y1/immf yn (s 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 change when he gai9oj9.;qay hoes from sea levea; aq 9ih.9joyl 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 q vu/001x 7pb+ trce1shisq n9satellite of mass 100 kg is at a point 3r above the Earth's surface. What is the sati0 uqs 10h/e1 rn9pstqb+x7vc ellite's weight?

  A spherically symmetric planet has four times the Earth's mass and twice io(eg0 ;6ps)vcthwr3 zts radius. If a jar of peanut butter weighs 12 N on the surface of the Earth, how much would it weigh on the surface of this plangv; pe) oz0 scr6h3wt(et?

  During a lunar eclipse, the Moon, tza vrq /1gqq:lk2t/omo(3fm 5e b5 2bEarth, and Sun all lie on the same line, with the Earth between the Moon andz(2oo52mab:mlqtv 3 1 /5/tqeqfkbr g the Sun. 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 transporxhv) o,n6e b1xted 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 czvvopf yxi r;4.*s-+ the Earth (i.e., it just skims the surface of the Earthp-coy ;if+s4*r. x vzv). 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 oran(w)k8nf .)1wltg5xg( 6obq /dfiy dbit 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 radius of the Earth6)f . d8q5ga)n/g w1ykwbf(xt(i oldn is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surface of the Earth3 r9+ rpxz79zdmo:m 9v pvgo*u. It is observe x vmg9+3p:oor*9rz9vm7d zupd to 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 Jupiter, has an orbiioxzk8pn ;y9 pgscq8vg(( 1ng4e27 yital 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 Jupitpkqogi ba+ne3,fda,/qi5c( re4 i-:ker 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 nearly circularxdse5i ()t -ouw6b lx4 orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long doetsx -xbd)6 o5w( 4euils it take moon B to complete an orbit?

  The planet Jupiter ixy)6jy 4vmnx5yg;f7nmh ;s28pu l1jt 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 orbit the Sun once. What is the avera ox /bjl-w6hk8ge distance from Jupiter to the Sun?-h/kxo6 b8jwl (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)