Is it possible for a86 s0 ke2kkhr6qel n-;etztt.n object moving with a constant speed to accelerate? Explain kk.zt6rn2t8 t eesk-;qel0h6 .

  Consider a particle moving with constant speed such that i (jk :yj8v5 cjc)to.uuts acceleration of constant )kjcu( 8ju5:.cj yvtomagnitude is always perpendicular to its velocity.

  An object moves in a circulmh*rzf.3oqw*pv i/ yye 1sf/a *+w;z car path at a constant speed. Compare the direction of the object's velocity and acceleration vefr*ec q31p/szy wh;oyaz/* w.i+mfv*ctors.

  When an object experiences 6 9r h .i-i9 3z1zmhvq3 dejoodk):topuniform circular motion, the direction of the acceleration ip3:z.r iokhojvh-id )eq1ot 9dm63 9zs

  Consider a particle movin 59 zzitu;m3bdg with constant speed such that its acceleration of constant magnitude is always perpendicula9u t;3mz5zib dr to its velocity.

  What type of acceleration954gbrpu m(si does an object moving with constant speed in a circular patrg9 u (bmips45h experience?

  What force is needed to make an objeued 1m60(:ay w/y /xh a/cvsfvct move in a circle?

  When an object experiences unifo) 3hsnned;3dm+ 82af wlbw6xlrm circular motion, the direction of the net forwfb6s3 m)a endh lxl83dn;+2wce is

  A roller coaster car is on a track that forms a j262x0 ah:d wexq mwj7circular loop in the vertical plane. If the car ihwx026 2j7:xjw eq amds 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 = M) is on a track that forms a circular loop (radiuyx gh;dfv0tebm54 v:1 s = r) in the vertical plane. If the car is to ju v0etmgv bx5yf:;dh41st maintain contact with the track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular arc until it ix86 (asb ; p73lkvljiis going straight up. Just as the plane is at its lowest point, the force on him isk pji 3(7x;8v 6ibslla

  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 rtk(ld 7b5z)lzadius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radiusu3o k-cy*u pes4aq. ;y0y hzx .uyd:0m file-4 r at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetalh0o-ylem0 uyu;ze ks 3ypcfu *x-4a.qd .: 4iy 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 speed v. Then ith/qkz x77wv k0 goes around a curvz/hvq77kw 0kx e of radius 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 a6q,b:eqt55fyo3 vjw v 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 of the normal force on the car from the road is equal in 5jb,5yfqqo ve3w:tv6magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, but oneh *6zrtf-muxtw1* m u6 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 tu 6xfm*t*r 61t m-wuhzhe safe speed on the larger radius curve?

  The banking angle in a turn on the Olymh*i)swg y-u3 vpic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower c-u3y hv*w) isgoming out of the turn. Why do they do this?

  Is it possible for an object moving around a circular pj+h3dey*ckb 0-0w msb ath to have both centripetal and tange0bb+ w*dsk ehcy-j0 3mntial acceleration?

  The gravitational force bt j+w igrj/u)66xr xk:etween two objects is proportional to

  The gravitational force between two object w;+rym vhl 8+hs,to*x2jc47md o y;pos is inversely proportional to

  Two objects attract each other gravitationally. If the dista*( t+- w enp mrv+nb3r4tbviwl00t*dbnce between their centers is c *n4+v(0nwbveb l0 tbw r+p r*t-3dtmiut in half, the gravitational force

  Two objects, with masqzu+ z)u*czce37 jqcv mmh 40ih3t5 s(ses $m_{1}$ 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 masses8 c)9fp1tg n y+f 5fw-m vom+ddx(/qfz $m_{1}$ 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 gra0vpvqyvlge lq)zo; e*58,st9 vitation.

  Compared to its mass on the Earth, the mass of an object on tr.( jkof:lz2l he Moon is

  The acceleration of gravity on the Moon is one-sixth5*bhkscd /zmlh2- bn1- g5 txu iu1:ahs+nj+z what it is on Earth. An obj/i*- bt n 1 b5h-jck ulzs2mhzun+ga+h:sdx51 ect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sur2j qlp*q z*n,a4+5o1n vb xrmkface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it be-+ vrnyuxv/8b yond the pull of Earth's gravivb+r/x -u vyn8ty?

  Suppose a satellite were orbiting the Earth just above thes0 /td 4c+zp, 6nb8bh5btcio j 1mm2ze surface. What is its centripetal acceleration?,ittbp2+ scc dze 1b4o 05 z8jmm6/bhn

  A hypothetical planet has a mass of half that of the Earth and o6 7y,h sgknn +1lya8wa radius of twice that of the Earth. What is the accel s g,+6a7nklw18yo yhneration 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 Eavqzyb ucisdct 2b 0 fcj4 2(o-02kvvw*b f:v79rth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compared to the Eart4jcfv:i -v ozbsu9t*b2bcv0kdcf2 7 2w 0qv( yh's?

  Two planets have the same surface gravity, but planet B has twice the ra+ vm + )2bnp h8k uyy;hl7l*,:xayjdsudius of planet A. If planet A has mass m, what is the mass of plxp8h+ sb;kd,jnl7y2vy ahu+) * y mu:lanet B?

  Two planets have the same surfac z. 1ffbu/dof+9v1nz8 4xa a d3;dxgtfe gravity, but planet B has twice the mass of planet A. If planet A has radius r, what is the radius of pln fffd tf/48oxa9v;.b1z azxgd1d3u+anet B?

  Consider a small satellite moving in a circular orbit (t-wx/a t *oqn7radius r) about a sphericalx7awq*tt - n/o planet (mass M). Which expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in t ,: aj;bz0t sdnchy7(she same orbit. Compare the two satell;(cb0t hyasd,n7z:s jite's speeds.

  A person is standing on a scale in an elevator acceleratisrp . 35o;np6hnf a hxy1c71iang downward. Compare the reading on the scale to the person's tru53rcyo1x hpa.ni7p s n1;6hfae weight.

  Who was the first person to realize .cxw,* v+4hg2)t 0beejs jb7 rtuktx)that the planets move in elliptical paths around tjt +c2wee) .krxb4uhvxg t*t) j0s7b,he Sun?

  The speed of Halley's Comet, a obx y8-ce:s-while traveling in its elliptical orbit around the -sx-ec8o :byaSun,

  Let the average orbital radius of a planet b 12vv/an4rjwt e R. Let the orbital period be T. What qu/ vrj want124vantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbitcx/p2+ xty3tovufa/d 3 kzi70 around a star 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, wha/k73da/3x v fttiupyxc zo+02 t 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 "astroj.cv6mhsx 0r e-c gh0+nomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sujr.ches0 xvhgm60+- cn?

State Kepler's laws.,g 1t5/ou7ca-wahv7j2 x2ngk mol8s c

  List the four fundamen7dx rh 8 gw4cdsb)-9sftal forces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of p ue kw0-th.tg960fqmradius 150 m. mp090qt hg fet.uk-6w What is the acceleration of the object?

  The maximum speed around a level cu:x 2aj7(gig 3tz3tstprve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all og(zts72xtpg aj : 33itther factors remain unchanged.)

  What is the centripetal acceleration of a point on the perik8/1t th:jk.bxan3lkfk cx tq/,6:l fmeter of a bicycle wheel of diameter 70 cm when the bibf jtk3/:c6kh, x.xfk1lqkat:/n 8tlke is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from thep /2dyugi6aa04fjzcws55: wb axis. What is thyug4 iw 02bd js/p55fa6zc:wae centripetal acceleration?

  How many revolutions per minute must a circular, 0saor0d nc,5pt pt 7k6xla9i2rotating space station of radius 1000 m rotate to produce an0lpdt9coi rstnx2a,605apk7 artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 -1;scyg))m xrvv 6zvp +ayyin v7pi,* m radius turn at 96.5 km/h. Whav pynx;aygzm+y )ivr7 i ,*1c)vs-p v6t is the centripetal force on the motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is -nm 0pydox..1fl wv61qk u9ljwhirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the max9 x.ljylwm1 0u6n.d o-v pqkf1imum speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong str.a vtq 4kv:xb47:7m ezayny8xing 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 z 7xa am 44yv:xq8 kyb:.en7tvpoint is given by

  A stone, of mass m, is attaxzy.p* wuvby,( pp/+cched to a 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'spzp(u x.pyv,/ *+wbyc speed at this point is given by

  A jet plane flying 600 m/r w 31sisj 2gzx/*nd3ss experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature ons1j 2r gx s33wi*d/zsf the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in whiban(qv 4(4e*7e v:vz-i ymt gich the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing down on his seat with only one-half of his normal weig *aygz (im eb7vtien4q vv4:-(ht. How fast is he going?

  The maximum force a pilot can stand is about seven times 3 j /7w1badhvnhis weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, cd37av1b hjwn/an tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with the tires ozh73/ fr ook 1ly5jsx.n the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assfl5orxso zh.3jk/y1 7ume 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 asz x 7n*gmi:hocih22 +5ag7v a speed of 20 m/s. The centripetal force provided by frictimh2ig5 7*go7n:+ zi2a avs cxhon is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat cuaim6t4 u7;pf vrve 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 7pvt6if a; um4car to make the turn?

  A car is moving with a constant speed v around;bl ::o3f-strw wf8k -y6er tbfda3)y a level curve. The coefficient of friction between the tires and the road is 0.40. What is the mini sfdr:b;eo wyb 6l-tfaf tw-3:3ry)8kmum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Oy 9)as9mi: 6z*pn 0nfbxcbc8ulympic bobsled to negotiate a 100-m radius turn at 35 m/s without nim n8:cu0b*)px6fabyz9 sc9skidding? (Ignore friction.)

  A horizontal curve on a bg +c:oiy-ey2q/ re bv0obsled 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 radius 100 m,-w st4vr s*pg;jf zr:f9tg3*c banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is banked at 3kxefo b)d)p6 0bb(tx$45^{\circ}$. 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 uniformlxpdo9e1.m13/d9r- 4yqq-6q0r fi ev gmh dnuqy in a horizontal circle oy9qrq.6/ pe v-eh-u iqd3 gf1xromndd4q109m f radius 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 cedqa4h9bxr7 .v a j1(mar accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. .4h( rx 9amed71aqjvb (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 consists of u5gxjj7(9efeizde .: 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 Ea e jkgmz7:y96orth, due to the Moon? The mass of t 9:g6y 7jeokzmhe 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 Fsw 2/gp.3ova ,neqq3f. If the masses are moved to half of their so 3a,qnwpq2v egf3. /initial distance, what is the gravitational attractive force?

  For a spacecraft going from the Eag)esa0i:+pd0 f l kt)krth toward the Sun, at what distance from the Earth willkeg +:d0if ks 0pt)a)l 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 isk ; c fq;(k)r:xsw q-r.ro(gkc $7.4 \times 10^{22} \; kg$ 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 impj)i tl8jyyk:9,(fa "space-walk" at a distance above the Earth equal to the radius of the Earth filpik:mjy ), ty(89j. What is her acceleration due to gravity?

  The radius of the Earth is R. br7 xpjcs4wp ivx0xzj:a1 ,p d4*-0kj At what distance above the Earth's surface will t0xx4c7p-jp*a :z4 xpri01,w jv bjkdshe acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above itd2qryyj 35)wj s surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceq5jrwjd ) y23yleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acc 408a q*lgzlerhfmxf 4iibf.x/. w3*celeration of gravitya 4m *ehlib.r4lf .x g ifqw/x03fc*z8 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 radius r.zx,0;a -f muiyuuz)p2 If the object is raised to a height of 3r above the Earth's2y )f -zuzu,m;xipa0 u surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when hps j(wt iroizpdb4q0l;g(;35e goes from sea level to an altitude of 5000 li od (q(0gjwb4s;5p ip;zt r3m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 ks.x 7hkz eq1 5z(*aunwr()yxzg is at a point 3r above the Ea(nqxz w *uz75r)(hk azsye.1xrth's surface. What is the satellite's weight?

  A spherically symmetric planet has four times the Earth's y frrje)w8(k.4a *wzathtr,0mass 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 surface of this planwkrw.f*t )h r0(4e ay, tjar8zet?

  During a lunar eclipse, the Moon, Earmfqtawpzf/d5/1 qn , -th, and Sun all lie on the same line, with the Earth between the Moon and thew t/1d,mp5qn zf-fa/q 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 the Mod2s. fg f*rbv: ngms(4l0il*e on.
(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 justsi.6f) mwchn;7w nt7j skims the surwf.mtwn cj7s;hn i6)7face of the Earth). 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.e., it g5ers/j(pe g mkid6.4just skims the surface of the Earth). How long does it take to make one revolu.rmji(4 5/pgg6 s kedetion around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circuld zv:0 xkpp d,d2/qkwv5v2a +z/r,lig ar orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of q2 plk, 0 prw/id5z+ 2k,:/zdvgvvxad the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupa3oot7 u5ovlrs:b9f .*k qao7iter, 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 fe8nk.vrxz*l(0 * (lit n uul-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 circulavwb2j 3)s2sm or87zq nr 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 does it takezm7b2wv osn 823)rqs j moon B to complete an orbit?

  The planet Jupiter issh3bq9m jg( -h+(9p4iqpu06acg typ n $7.78 \times 10^{11} \; m$ 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 owk1*h/tf o4 tmc7wo*)imn *l to orbit the Sun once. What is the average distance from Jupiter to the Sun1owm/*k )t w 4t*fch*o il7omn? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)