Is it possible for an object moving with a constant speed+d iw. *x0fyid to accelerate? Explain+i 0wyd.fdi*x .

  Consider a particle moving with constan b(x0em-f(yt8n0x ited9q7 s3 ako*nkt speed such that its acceleration of constant magnitude is always perd(ettb0f9qa8sxn7(y i *-kx om0 en3kpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compgw:po-a hlq80are the direction of the object's velocity and acceleration qg- how0ap:l8 vectors.

  When an object experiences uniform 9wzvy9 a3y og0circular motion, the direction of the accelergwoyy 99 azv03ation is

  Consider a particle moving with constant speed such that its acceleratiou*ohtc 3m 6d*yqw4wt2 fz5;jdn of constant zqwh3c2w 5dj** tyu46;dmtfo magnitude is always perpendicular to its velocity.

  What type of acceleration does an object m7 j:q4 ttvug/moving with constant speed in a circular pm74j :v g/tqtuath experience?

  What force is needed to make an object move in .z0b0ezlf 8, dt r0fnja circle?

  When an object experiences uniform circular motion, the direction*rqv- k bcehdzw:tk;8 ye60*f of the net force0zr6bt e :;*y8hcvw qkkf de-* is

  A roller coaster car is on a track that forms a circelalg u32g am/q2-7lxular loop in the vertical plane. If the car is to just maintain contact/la -2gux7 llga2qm3e 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 circular loop (ra /pc. x-7rqu+wf.wiih6 us w7qdius = 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 itu wwf/s7 7ri huqq6 .+xc-iw.ps speed at that point?

  A pilot executes a vertical dive then follows a semi-;mt0. b wwt6 5i9elwm abli./vcircular arc until it is going straight up. Just as them 0w9tb. 6iiw/tmll.;b eaw5v 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 radiv r:p pmmcj804us $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a 6r3i++sakp+; ia:rrfjq wa.p curve of radius r at a constant speed v. Then it goes around the same curve at half of the origi3+kipj;r+6 sr +qwaf arapi.:nal speed. What 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 ra-f)q3ij:5fy/o u dmjedius r at a constant speed v. Then it goes around a curve of radiu/jmd-:i oqe y)fj5f3 us 2r 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 around a banked curve of radius r with speed v. xa 3*pjgvan.5s a)d0zgdt55/t4yxnc If the road is frictionless due to ice, the vt 4*zap 0nt)jc.n3g55s yxax ddg5/acar 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 on a bobsled run are banked at the same cu3o71 rrw-hm 6bk ux/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 t kwur/o71-chu x63mbrhe larger radius curve?

  The banking angle in a turn on the Olymp3ab(r4s6ks*-wbyncx 0i d: szw;mz/ u ic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsledrin;d(wms* bxu-/ 40wb:szk 6 csz3ay 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 bothjpk6 7 .uam:jg centripetal and tangential acceleraa: 6.kg umj7jption?

  The gravitational force between two objects is proportional to l,ft2 y/exanyln ;1d5

  The gravitational force betweenoj*p,9u1c stb w po(2l two objects is inversely proportional to

  Two objects attract each other gravitationally. If the dis.k )85 t0knyj.v2 gt/ l dgilrq,.czjftance between their centers isjdzt j8y0vi/) t.r2g ,knk.g 5.lfqc l cut in half, the gravitational force

  Two objects, with masshrs7d cn,*go8 qpqjny6b)g5(cc60a nes $m_{1}$ 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 massee34s20 tmimuzs o n1)ag7q*eg s $m_{1}$ 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 gu*/( *; lfs t/vgwtc/g6zrzkpravitation.

  Compared to its mass on the Eartnu:( 2v ilnzhu: jq8.wh, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth what it- jbwff9jlugl)**z 2f *fqyo) is on Earth. An object of mw -z9f2fl ofgf)uj* **b)yjlqass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away f9jvr a:3m+tvf 9ff;zqrom the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point i -lwuioc2.o,x:n2g xf s it beyond the pull of Earth's gravi2io.fxx:,w cgloun 2 -ty?

  Suppose a satellite were orbiting the Earth just6*fv :pe,vivw acadq wk/*t1 t*m ji3- above the surface. What is its centripetal acceleratioce6i-/ijwd3:vt*v 1t aa fvq* * kwmp,n?

  A hypothetical planet has a mass of half that of the E h 4h)mw58ugkyarth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleratymu 5hkhg)4 w8ion due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. Th nf, 5,kxanzmq2u2y3 qe radius of the Moon is one-fourth that of the5 2a,uz2,fqynmknxq3 Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B (v2 a(moiia.d7j8 qfb / jtdx7has twice the radius of planet A. If plt( 7 d.7b8ai2ajmfq doj(x/ivanet 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 ody-ns xm66mb) f planet A. If planet A has radius r, what y)mdnb- s6m6x is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) jw+:-+ jfiryuabout a spherical planet (mass M). Which expression gives this satellite's orbit yfjriu j:++-wal velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit.n5 p4q, 2jdudeqd sz63 Compare the two satellite's 2p4ude 5z,nj6sq 3dqd speeds.

  A person is standing on a scale in an eleqel lfu5sb;tmh s v28ut3r40*vator accelerating downward. Compare the reading on the scale to the4l* 0 vl8eum f5uqtbh3rtss 2; person's true weight.

  Who was the first person to realize that the planets m:l)c8y n/edzpsmd i 93ove in elliptical paths around t3d:/dyci) z98 nempslhe Sun?

  The speed of Halley's Comet, jtjsat+d+;c1z qqr 4+t(:w l wwhile traveling in its elliptical orbit around the Su 4w atqc sj+z+td :1w(ltq;+rjn,

  Let the average orbital radius of a planet cis.y6 (+bdo obe R. Let the orbital period be T. What quantity is constan bio+ds. c(y6ot for all planets orbiting the Sun?

  A planet is discovered to orbit around a staruvzi r5mi9x k; 1h6jllvbk3 ;20w,toq 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 revolution of that new planet be, compared to the Earth's or v;rwzqku,5ot; mh l jv3 2xl69i0i1bkbital period?

  The average distance from the-(2 l wxoy5bub Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-tbyw-l5 2b (xouhird of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.lf*rbc jd4h+8x2hke6c,w it,

  List the four fundamental forces in natureq+pg;/c f;jjoc8 q(dxeb3v /k.

  An object moves with a constant speed of 30 m/s on a circular track of radius 1u mj80 n*(psya50 m. What is the acceleration of the( j0 mpsauny8* object?

  The maximum speed around a level curve is 30.0 km/h. What is the ma-lhs*7xn o mzj 2z7h)fximum speed around a curve with twice tsnhzl2j)z7- fh7xo*m he radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of uz6oa2 wonh, +ivn4g/a point on the perimeter of a bicycle wheel ooon2z h,a6+u4/ gin wvf diameter 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 f:d9sp2. wbu7qt sd oi)rom the axis. What is the cen :ss2 dd)poq7w uti.9btripetal acceleration?

  How many revolutions per minute must a ci ubja)lf6 r,u 35zbi;q8mz9e trcular, rotating space station of radius 1000 m rotate to produce an artificial gra3b,irmle 85; z ub9u)a qz6jtfvity of $9.80 \; m/s^2$?

  A motorcycle has a mass e+nm2noqelca0* e+ p2* k4b1qnxz) xdof 250 kg. It goes around a 13.7 m radius turn at 96.5 km/h. Whk0xe cmnz + )4n2q+xlqd2n*eop1b e* aat is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end8+6x r+ / z+ryvn1xyccm cy*kd of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximu zcy+/6kx*x+ v8ny+ c1dcrmyrm 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 stro3 tri ug32jigk s(+,)gor9krxng string and whirled in a vertical circle of radius r. At the r9)ogkukrt 3s2ig+ j3igr(x,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 strin2c 5rjx shcc37g and whirled in a vertical circle of radius r. At the exact bottom of the patscj7 2xch53rch the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experience.jkxycl.mv+nbg * a.*s an acceleration of 4g when pulling out of the dive. What is the radius bcjagvm *x*l...nk+ y of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center ofi(z:u z 6u ,tmj.dcb,v the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing ijb6 u:zvmz ,uc t(.,ddown 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 py4fnmvd m4, 4is the minimum radius of curvature that a jet planemyvfp44, nmd4'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 1b2dzpv/lqbt/t gfhij408m 632ugpvd8,pz ehorizontal curve with the tires on the verge of slipping. How fast can this car round a second l/ jdpzt3 ebp1/,vqgg2zv6t4bf 2p8 0ud8m ihcurve 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 curve of radius 50 m with a s78el yqii:lv y .cvn/-peed of 20 m/s. The cent l8 yyv7c.-: vei/inlqripetal force 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 14 m/s. 9m j 2+n(a6w5af-2mzwcuoua lt6t v2cWhat must be the minimum v9 c2wzm+2 ut5-ocn(6l6jfa2a amt uwcoefficient of friction between the tires and the road for the car to make the turn?

  A car is moving with a constant speed v a8+7vbpfmeyr.l:1(c ye; ygt. ) lltbsround a level curve. The coefficient of friction between the tires and the road is 0.40. What is the minimum radiu 8.s ly eyc1t. me+lr()pgvbtl:b;yf7s of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled tj+uf 0 +r(70zcxvbwd zo negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore frictrzw d0+x 07(b+vfuj czion.)

  A horizontal curve on a bobsled run is bapz(8 7jn:+u0xwjqgb wnked 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 acba c)2gf h6)lzr+3vpn angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at a;9i;8 8bdq9nbskem1 4t, w/ iuxmvae$45^{\circ}$. 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 the4u6 kf.iyxrc0 end of a string is revolving uniformly in a horizontal circle of radif k 0xy6rui4c.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 uniimy 05x1 bn1rdform rate to a speed of 41d0y 5n1 rimbx5 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical 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 cos l n3y;:u.pmrnsists 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-kg person standing on the Eaoop,dbj9;; qgan4 8uhes9;xyrth, due to the Moon? The mass 9ap;hn4;j 9,u bxodgs; 8yoeqof 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 i1: :ydgj:wy j24w pvo07uldmF. If the masses are moved to half of their initial distanc: dj421g:m:0ju wwyoid7 pyvle, what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sh:-b:c qhn*h;w)x2t1gfwsp k un, at what distance from the Earth will the tw1qkxp h: c2ghsb)n*;f-hw: 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 jpml7swp ,n);$7.4 \times 10^{22} \; kg$ 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- gqctl29 (j+nfwalk" at a distance above the Earth equal to the radius of thec9+( jqlt g2nf Earth. What is her acceleration due to gravity?

  The radius of the Earthqq:;,r eiki mo qg2fb1+ys 0*z-+sjo p is R. At what distance above the Earth's surface will thof10jrg* +e m2;p qi +zyqks-o:q s,bie acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles qj)o: s ,)klqlMars at a distance above its surface equal to 3 times the radius of Mar)s q jq,lo:k)ls. The acceleration 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.qbjlj/vt o8dn9oag8h z *nl 63.4oit some planet's center, the acceleration of gravitytitldh/3ao jln*b4z9q n j.8g6.o ov8 is $32 \; m/s^2$. 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 rat p3+/k 6zwu5fclf g pise9/i e3j(s(mdius r. If the object is raised to a height of 3r above the Eai3sucsf w+ l 3e/jkfgmpzi9 (6t/5ep(rth's surface, what is its weight?

  By how many newtons does h+dok8epka .;l n- ;cd*m yyo:the weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean radi- eamy;n :cly8kho.dpk * d;o+us of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A (amsh rf4 /f1lsatellite of mass 100 kg is at a point 3r above the Earth's surface. What is the satellite's weight?/f mhl( r1afs4

  A spherically symmetric planet has four times the Earth's mass an2zz-)/2z ;gywjjc wz/a43e,blqbqdcd 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 surface of thisca2wq,q dz ez2bbc;wy ) l jz-/gj/4z3 planet?

  During a lunar eclipse, the Moon, Earth *xta a0m+qua(l ;w0af, and Sun all lie on the same line, with the Earth betwet0;a l(qafux*maw0 a+ en the Moon and 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 transported to 43 ,nt( sgcmpkax.wh8/xuau0the 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 just skims fj+kgsv9 q,e:the surface of the Earth). What is the speed of the satellite? (The mean radius of the Earth issqk,:9e +jg fv $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earthsprw.f+e )yd; 4pb aovw.to2otwd6*e 4 m/fu+ (i.e., it just skims the surface of the Earth).. pt6/*os dom +.wre4f o;dtfp+uaw4ewy v)2b How long does it take to make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular +ooo dkb9ib.) orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Ei+dbb9o. ook)arth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an or7 v-xlb5ap) ssl;.h 9)jlyy nlbital 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 with bwmu-+kx lt+3 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. Mym4v c 0ejo60roon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. Ho 4ry6ve 0c0mjow long does it take moon B to complete an orbit?

  The planet Jupiter isbd mczl56 i, g(axiztz96p( v0 $7.78 \times 10^{11} \; m$ 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 Jupitero;kxy shv rciln2( +nv6j5q 6z;4v7yl 12 years to orbit the Sun once. What is the average distance from Jupiter to the Sun? (The distance +o7c6vl5k vh 6qnin lyxv4(z2; r yj;sfrom the Earth to the Sun is $1.5 \times 10^{11} \; m$.)