Is it possible for an object moving e2e7 xv 3sojg .sbp2 8wch4;lcwith a constant speed to accelerate? Explainp2 7.bv h3 c8o2gljcew;ses4x.

  Consider a particle moving with constant speed such that its acceleration okyzysn7y35 c1f constant magnitude is always perp3ncys1 yy7z5k endicular to its velocity.

  An object moves in a circular path at a constant speeg,e1fg hj5c 7bm44ghfqmz. x+d. Compare the direction of the ggh4 mbfj+m.7gzf 14h,x ceq5object's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the acv pfg:i 2kgv q.-/0qlzceleratigq -lzfvqvg0: 2.k/ ipon is

  Consider a particle moving with constant speed such that its acceleration of uu9a1ios j904knym 5ivl* l*zconstant magnitude iky*io*zm an 4uli9sj9v1 05lus always perpendicular to its velocity.

  What type of acceleration does an object moving with constant speed in a ci742*ybrwi *k tt: tuhcz* qn.jrcular path etbyjn4ctr * t*q2u i.h*k:zw7 xperience?

  What force is needed to make8bs9s l9+y:yno17nxx )ct t nc an object move in a circle?

  When an object experiences uniform circular moti ;go9m(ima o0von, the direction of the net force isoo(v0i9;mam g

  A roller coaster car is on a n6 .4kf fsz*ws;9 o.rnex4h7xu xa/dztrack that forms a circular loop in the vertical plane. If the car is to just maintain contzo7 fzu /s4kex.da ; wnns hfr9x6x.*4act with track at the top of the loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster carxjaj*4oqsn l-01o,a xyb * h/o (mass = 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 top of the loop, what/na 1yjj,o0so4x*o- h*a bxql is the minimum value for its speed at that point?

  A pilot executes a vertical dxac va4:0t j2sive then follows a semi-circular arc until it is going straight up. Just as the plsa42v 0x:tca jane 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 radiup5c9+ lw)rxdiedd m- )s $r$ 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 casf1o8a;+: v kexwqzxl7s - (bonstant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the caa ;1 x8-lqzak wv+sesx:(7fbor as it goes around the curve for the second time, compared to the first time?

  A car goes around a curve of r- z /8dbhv8zetadius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around thzezt8d/8 vh b-e second curve, compared to the first?

  A car of mass m goes around a banked curve of radius r with speedn5bh4ca ll +w8s2u *wc v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizl bs45*a h2w+8cwluncontal 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 angle, butv 2lvh4+t. 0 pik uzpa9n6+uan one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radlv.+k+a nu0 69 4ippnuva2tzhius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic(lmjbsv v2;/* l.wz + cyziaigl*4f 1p bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsl+yj4v *c lwf/ vil. 2pz1ml bz;i*as(ged 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 bot g*lirxmxtxh) 0+uk.3h centripetal and tangential accelekx+ lgu rt3*x)0.hi xmration?

  The gravitational force between two objects is proportionkwc09 bmb-pu n hia -8l()u(ioal to

  The gravitational force between two objects is ir a*hlhlfa,9 eql(z81h v) 8dcnversely proportional to

  Two objects attract eig +q-u6 lelv, gm9pz 9jkb19qach other gravitationally. If the distance between their centers is cut in half, the grav 99gk1bvg-j+ql9 i,6qzu mlpeitational force

  Two objects, with masses foz ii3w 1a/r($m_{1}$ 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 v-ymiz9 4v f+i7 lpx/zse; d y70k0hqt$m_{1}$ 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 gravita 5oxf.4brsd -n b2hjl;tion.

  Compared to its mass on the Earth, the masspusf(9 m0 1r ;yhe5ysl of an object on the Moon is

  The acceleration of gravity on the Moon is one-sixth y h.ryhi**ju -what it is on Earth. An objuh-iyj .*hy *rect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away frpqxep./1 vazjq+2-7:f rro r gom the Earth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyond the pull)/m v 6sq8gnrrh6b(j h of Earth's gra6r bq h)jgmhr6/vs8n( vity?

  Suppose a satellite were orbiting q/ *wvhzqf)j:* i:il jthe Earth just above the surface. What is its centripetal accelerationliw*hf: vz )/ :qq*jji?

  A hypothetical planet has a mak3 p,-4tmon8n zmrpv,ss 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 terms of g, the acceleratp v4m8kt, nm3-znpor,ion due to gravity at the Earth?

  The acceleration of gravity on the Moon+dzuyxr ( l6t2 is one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. What is the Moon's mass compartl26 dzu+ x(ryed to the Earth's?

  Two planets have the same surface gravi nuqd*ge ee*tj1.8m8qwks x/+ty, but planet B has twice the radius of planet A. I**1gu+8nq wm .sqt ekd8/exjef planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planet B hpkwpu - 6g.j2fas twice the mass of planet A. If planet A has radius r, what is the radius of planet pk. p wgj6-uf2B?

  Consider a small satellite moving in a circular orbit (radius r) rcljs4. l j(,eabout a spherical planet (mass M). Whicj(je l4l ,.srch expression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotati*.,se. z u8ik.jwohab 3m.tues in the same orbit. Compare tjz.,u..8ot. 3imh*uikbwaes he two satellite's speeds.

  A person is standing on a scale in an elevator accelerating dow(maa7 de3-u5b 0nj eodnward. Compare the reading on the scale to the persojb- a oue(mdad3e5 n07n's true weight.

  Who was the first person to realize that the planets moa+ 8/0 m knrm3b);yw/ bzmbvmg0zlg,mve in elliptical paths around the mz m/08m;w )z3vgrm 0y,lkbg +m/ba bnSun?

  The speed of Halley's Comet, while traveling in its ellipfg1s: ,n( dz j1 1a:6svlkmnartical orbit around the 11af, dss nj azm:v klg:16n(rSun,

  Let the average orbital 3o h8o8mx (z/aisbt3a radius of a planet be R. Let the orbital period be T. What quantity is const( os3 8axo8hzi3 /mbatant for all planets orbiting the Sun?

  A planet is discover s5jjo :2)sp)jzvzvv 0ed to orbit 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, what will the period of revolution of that new planet be, compared to the Earth's orbital v) o5vzjjss2)z:pvj0 period?

  The average distance from the Earth to g1 *xnosw7 e v78a3sg0gkak:tthe Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sunggexs *7nsa: 1t8w3oag7 0kvk ?

State Kepler's laws.n ti(1, so-ual

  List the four fundamental fotdzbd 06 9gec6ef9jx .rces in nature.

  An object moves with a constant speed of 30 m/s on a circular track of radiu0+kgo nst4 oyrjg 5p54s 150 m. What is the acceleration of the objectp+sn45k0ytgg o r4oj5?

  The maximum speed around a level curve is 30.0 km/h. What is thee 6kaylj7m2 o-xnfe0(r ir48 e maximum speed around a curve with twice the radius? (Assume all other factorsinr-m46(k e 8flyar oe02j7xe remain unchanged.)

  What is the centripetal acceleration of a point on the per;j1gajk03i-amm 8ls b 6csyt5imeter of a bicycle wheel-gs1l;j 5aki ya6s0cm8t bm3j of diameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating8*gi nml0o +le at 5.00 rev/s is located 0.200 m from the axis. What is thoige+*l l m0n8e centripetal acceleration?

  How many revolutions per minute must a circulachix+ b3 i- rs2fac5k;r, rotating space station of radius 1000 m rotate to produce ir a b h;-3scfxc2+k5ian artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radixw r;.r 3s3zudvks:-ous turn at 96.5 km/h r3d.x3;zk v:uso-wsr . What is the centripetal force on the motorcycle?

  A 0.50-kg mass is attf6 r6p hn4upa oy3n3t,ached to the end of a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tennfr u64,ayo h ppt633nsion 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 whirg/ lhe)3yoa2p led 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 ta/goy3h)l e2phis point is given by

  A stone, of mass m, is attached to a w ).miu.j( q7plfndxro;u4 ,gan)i 1wstrong 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 iim)(.7nuqu ,do )g4x rf.;a1wpnlwj this point is given by

  A jet plane flying 60 x)u umdsp1c)0lgi g1.0 m/s experiences an acceleration of 4g when pulling out of the dive. Wh.s1m dl1u0 guxp g)ci)at is the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertnqx1z )z,j3 h. tghb.qical loop (in which the center of the loop is beneath him) of radius 3.qg3j).b,nz1 qxh t zh200 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 abo s9aa9rhv1nu h /gw ruj;lpc-(ft 8-+wut seven times his weight. What is thv-9w/ulf h9pra (jgs 1u8a nw+ht-r;ce minimum radius of curvature that a jet plane'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 radiutnxt4.mm f( nrc/u*t8s horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient o.4tcnn / t m8f(t*umxrf friction between the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m k+*vl 6fo;x6bd7p0h s7f j e l8i cqx6telr0o(with a speed of 20 m/s. The centripets0lp6v6fdec(k fbo oh*l0876ejr;tl7q x i +xal 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. What ;+kf3 -ita hh5uy9 ttp0nrg z9,f al1smust be the minimum coefficient of friction between the tires and the road for the car to make t30 i9a5gath n-kfy ztph+rs t19;l,u fhe turn?

  A car is moving with a constanyj8rs+x tchgvru+*v, 60aq 5kt speed 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 cq0k6*usacj+t 5rrvh8 +yv,g xurve if the car is to stay on the road?

  What minimum banking angle is required for an O ; ys:mlnr bhhv8r/r.,lympic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (.vrm hhsyl;r:b r8,n/ Ignore friction.)

  A horizontal curve o:*gxbo2qu) 9paneoa-sz4 d2n5 eii o3n a bobsled 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, banked at an a l,y5txuldz8;l 8 za-sjp c*o.ngle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bmloqa3mimft n/ (6(9m 5. f sky k5swqh:4rus-anked 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 ofh/6a mdy p:xkxq,m8::ms fpv* a string is revolving uniformly in a horizontal circle of r,qxfmd: vp a/y8h :m:k*mps6x adius 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 : 6vee4fbkql7 area, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circula7b 6vkeqf4el: r 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 consists of a proton of massmqbx;m*5pi ym.*53p4kxkt v o rn 4b9v8p 5nvj $1.67 \times 10^{-27} \; kg$ 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 forw8 ri2-5e5 jzg u 6wgr:fna+27nevtr lce on a 70-kg person standing on the Earth, due to the Moon? The mass of the Moon75jlv+- rtfier e rg6naw8w2u5n 2gz: is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force3q0 by/tdc:q ;(ntz/5g uxg xy between two masses is F. If the masses are moved to half of their initial distance, what is the gravi(z: 5c0bgtnqg3td/x ux/;y yqtational attractive force?

  For a spacecraft going fcrj 7f8:u4 lqrrom the Earth toward the Sun, at what distance from the Ea frjr 7ql4c8:urth 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 isy-p*eua zkk1.p73drz $7.4 \times 10^{22} \; kg$ 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-wal5h5wb gtux t3ghr3x 2(k" at a distance above the Earth equal to the radius of the Earth. What is her acceleration 5( g3rgtx2 wubhx 3h5tdue to gravity?

  The radius of the Earth is R. At what ;tp.uvaq;gbf )1sb6a distance above the Earth's surface will the acceleg a6 u);.pqfbb;t1sva ration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distagwnv rg s.q)530m mdo7nce above its surface equal to 3 times the radi )v57nmdmsrq0ogg w. 3us of Mars. 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 khq59je zqctk 1-3 hw1xht8(rxm from some planet's center, the acceleration of gravityk- 98h 1h3hxxw1tt zrcq5 q(je 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 surfad5 +-5qbjygw3jnc;p hce of the Earth. The Earth has radius r. If the object n pjqwcjyg53db5h ;+- 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 change when he goes fr,-n+y h4 qpcw 7g5yisvs-ava8 om se7vw5 y,sahc-n ps+g iy4-v8aqa level 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 satellite of mass 100ufyhr hh 2h7/* kg is at a point 3r above the Earth's surface. What is the satelyr7h*u2hf/h hlite's weight?

  A spherically symmetric planet has four time9q)e(u bpkcrr(lu5m *s 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 *5rm(k)rbclu ( q9 eupthe surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on thettsp2vq:/kk( da pf9ui 3t/e+ same line, with the Earth between the Moon v/kia9qe:2+ ttutfds(3p k/p 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 th9 27dtjdwjwa/e 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 circularhpw :n2eg+4 gd(kuf(p orbit about the Earth (i.e., it just skims the surface of the Earth). What is the speed on:fdwk e 4gpp u((gh2+f the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbitfr;3in:jwh3 sw k rs3) about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around t3 irwhsj3fwks r3:) ;nhe Earth? (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 Earth.gx* dn2v8 n (iq q6v,z7irmvvi o)i)w2 It is observed to have a period of 89 mini 6iv,(mi iv)q vogn*x qz v87rdw22n). 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 diameter :ap61tgv;bfac9pxby:i / . i wof $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupite5 o8. ewcyds(.q*mdo(kqtd 1ar 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 circular orbits. Moon 8 ibks1uf(4 ia;2wdbkA has orbital radius r, and moon B has orbital radius 4r.ks bk42wi f biu8;1d(a Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter i9 d2,fvidrvg )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 aub()n qj6rff6pty9k/1f2hf3 pyzup l+l) q/ dverage distan 9l/uyuhl d3/p16kr n6+j(qpb)fff tf )2pyqzce from Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)