Is it possible for an obkl (syh++z 0hrject moving with a constant speed to accelerate? Explainrh +0(ky+l shz.

  Consider a particle moving with constant speed such thf- dud+;n2in xat its acceleration of constant magnitude is always peruxd2+ n-; infdpendicular to its velocity.

  An object moves in a circul gvzu(r3:d9fvooqjo,c+p* f5ar path at a constant speed. Compare the direction of the obujrc:o+f ov(p d5f *z3q g9ov,ject's velocity and acceleration vectors.

  When an object experiences uniform circular motoky4gsox +ga; *3nns1ion, the direction of the acceler+a1nxssyoknog3* g; 4 ation is

  Consider a particle moving with constant speed suc cv/b4j1ddvp i. u,v/ph that its acceleration of constant magnitude is . pc,j4bdvv dp/v1/iualways perpendicular to its velocity.

  What type of acceleration does an object moving with constant speed uh +yi) 5vbuj8 ytvqj,9.lt7qin a circular path exj7y) ui vyl59bt. j8qt,q uv+hperience?

  What force is needed to make an object move in a circlols8/x cep8z;4u02c,wi f 4hlo t n6gse?

  When an object experiences uniform circular motion, the 90prjd)5 hmxn o2rbj1 direction of the net forc pj0 x)2nro1rd59 jhmbe is

  A roller coaster car is on a track t*uit0 3wiz 2cihat forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loopizct0u wi3*2i , what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car yqbg4 k.0h j 8g53ncslrhi7 )kf1t e/e(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 b)l7 hsqy81t4e hjr3n.egki/ kgc0f5 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 semr0 x61dvt d-3ff +mzavwql-/vi-circular arc until it is going straight up. Just as t6vwd vlqt0xmr1 df/z-3-f+ a vhe 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 radius2cl.m6ihfmh 4oy.nl ,7o48eig s/b tv $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve odhdne: 2, mubb4dlg2r +6irp2 f radius r at a constant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around the curve for the second time, compared6:biu d4bmgle2d 2pd rr,n+h2 to the first time?

  A car goes around a curve of radius r at a constant speed v. Then it goesr ;x22ukow7zi around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goes around the second curve, c7ixku2rw ;o z2ompared to the first?

  A car of mass m goes around a banked curve of radiu0/ro in1yrph6c ,fwsw7pi* 5 uje2w,hs 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 tho ew n,jr sp,fr7iyhpui*c0/h6 2w15w e car from the road is equal in magnitude to

  Two horizontal curves on a bobsle (y; 77wi(9kpodhalzj dxh51sd run are banked at the same angle, but one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller r1wks5 li ;p7ohjd9xzy ah (7d(adius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsugflf8 hc+u1 -led 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 coming out of the turn. Why do f-cg lhu1+8uf they do this?

  Is it possible for an object moving around a circular path to have both centripghe qep6g(-yjw;m.p)5- auu gke x*f8etal and tan ggfg-p-*5mu )e qape.y6k8u( j;w ehxgential acceleration?

  The gravitational force between two objf.h ruj6p/ht m(lu+ 6o kbpa xv60)/fpects is proportional to

  The gravitational force between two objects is yz6 qrcl3mgnj).1 hr(y so.k*inversely proportional to

  Two objects attract each other gravitat*7qqzj t/k2b u 5jjoohp v(i8,ionally. If the distance between their centers is cut i ojzt(2oqvp57 8 h*,kiujjqb/n half, the gravitational force

  Two objects, with mas47r*jnsneup o4w) hxd uq1h 5: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 massest3ocxv qka-83 $m_{1}$ 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 uns4 1utin88.h zhnsi 00q. xv-vbfu w6yiversal gravitation.

  Compared to its mass on the Ezlqc cr1du3bs-2l - .rarth, the mass of an object on the Moon is

  The acceleration of gravity on the Moon is b6f p pt:1,4czd/k zlkone-sixth what it is on Earth. An objeccbkpzkz,t/ p46f :dl1t of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Efd-y3w6(rbh garth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point is it beyw o gojs0i;,: hw;6rltond the pull of Earth's,;g ol0wt ; oj:wsh6ir gravity?

  Suppose a satellite wer.e4 xn8n 0wtcfj/cql)mxt/ 0i e orbiting the Earth just above the surface. What is its centripetal accelerati/f)xxjm c0n i4lqwct tn8 e0/.on?

  A hypothetical planet has a mass oo7u+a9(b.rg4; lria kk c*zspf 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 acceleration due to gravity at the Earagsopc.k7 *r+u 9k ilbza4 (r;th?

  The acceleration of gravity on the Moon is one-sixth what g dylk26z 48szit is on Earth. The radius of the Moon iy4 2s6zk lz8dgs one-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surfv-f:avyp+q252ylc w sace gravity, but planet B has twice the radius of plaq2:5pw-cys 2 fv+vlaynet A. If planet A has mass m, what is the mass of planet B?

  Two planets have the same surface gravity, but planj0(2-pz sg zbsakl/,qet B has twice the mass of planet A. If planet A has radius p 0j- zl/szk, g2abqs(r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbitu0ak wx:.6ju u (radius r) about a spherical planet (mass M). Which expression gives this satellite's orbu:0uj kw6 .auxital velocity?

  Satellite A has twice the mast0*mex0toiu *-wph vgr(o*v2s of satellite B, and rotates in the same orbit. Compare the two satellite'p h0 *tv2 igo(xowue*m0 rvt*-s speeds.

  A person is standing on a scale in an elevator accelerating downward. Co d:vmwcs +,+wxmpare the reading on thsd+vw+cm:, xw e scale to the person's true weight.

  Who was the first person to realize that the planets movhon b eyn:/im95hvk.(fz re12e in elliptical paths around the Sub1 kme r2.:/h5 hf(zn9einv oyn?

  The speed of Halley's Comet, while traveling in its elliptical k- /cx 8(4gk:vpvcqsiucw* -p orbit around the S ckwgc-:ikp-/pq*4v8 sxvuc( un,

  Let the average orbital radius of u2jh/ bvr vi jgi0.4-leew6/ ma planet be R. Let the orbital period be T. What quantity is const .lv/bimeiv-wru46jeh g02j /ant for all planets orbiting the Sun?

  A planet is discovered to orbit arounm 4 53p)uht0t k/yjh7 lt*smald 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 toham mk50tp7*y4hl3)jt/ ulst the Earth's orbital period?

  The average distance from the Earth to the Sun ism1( k*/1 bjhs rgbr/tg defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is bm g/s brrh1g/ *1jtk(the asteroid's average distance from the Sun?

State Kepler's laws.1da9 bd368ieo wrlyo ,c/uo(q

  List the four fundam oui7 s5 y*oou0h7 nctvc-x1s-ental forces in nature.

  An object moves with a constant speed of 30 m/s on t jows:62a esy1 f0 x-x9gllf/a circular track of radius 150 m. Whatlf t6g9/ :sa ol wxf01j2xesy- is the acceleration of the object?

  The maximum speed around a leq3. klwuyeru++o5 (k)lpve 4evel curve is 30.0 km/h. What is the maximum speed around a curve witu+o5)q 4+v.erlue( l pe kyw3kh twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point on thvj7+qe vt ch-z,::mqp e perimeter of a bicycle wheel of diameter 70 cm :z:vepqj vc hq7-+,tm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rf; zq 2wg-a n mjmx/q99td*r2zev/s is located 0.200 m from the axis. What is the cen2mzj x9g9/n2 rda-zqq;tf* wm tripetal acceleration?

  How many revolutions per minute must a circular, rotating space station ontg:b) +xrz+ tf radius 1000 m rotatn+ bgx +:ttzr)e to produce an artificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7 m radius turn at 9g -9jytz/ v 6t1a1nfwv6.5 km/h. What is the centripetal force on the motorcy9 ag1vf -wzv tt1jny6/cle?

  A 0.50-kg mass is attached to the end of a 1.0l7anq,4jcmh kw -14q c;c,z uz-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 the4h -czm,41wclqknca z,jq7 ;u mass if the string is not to break?

  A stone, of mass m, is attached to a strong/9:x b 7q+r tuq,togsy string and whirled in a vertical circle of radius r. At the exact top of thebqt ,o+/9qrx ustyg7: 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, is0t,sj91qu zsx3wdmc hf e2*m, attached to a strong string and whirled in a vertical circle of radius r. At the exact bott,jh c 1tw0 mde*fqx3z2msu,s9om 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 jet plane flying 600 m/s experiences an acceleration of 4g ww wqdd:v w)1ftx9), quj ,e40tx 1lizuhen pulling out of the dive. What ,t qevutdww41qi9 z,ux 1jd0:xw)f)lis the radius of curvature of the loop in which the plane is flying?

  A pilot makes an outside vertical loom5me5p1sxbl2/ xz rk1p (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing dow55mz2p1/e lbs1xk xrmn 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 yjn *4dmt amh:: 6oudqijy/+4 the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate aj*y:miu do/+ya 6j 4d4h:qmtn t a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m ra rs/a1t83)f.dv bv jj:purk ;pdius 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 of friction betweevpr/ pk) r.bj3st a:vu1;8 jfdn the car's tires and each road surface.)

  A car is negotiating a flat curve of radius 50 m with a/m xo(gq29od s8o-aabf( qpa / speed of 20 m/s. The centripetal formqa/(qbd(os f2o 9xg8 po-/aace 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 mu*j 6*sqn euoiq1t)m 6pst be the minimum coefficient of friction between the tires and tjq* *o pmue1)snq6i6the road for the car to make the turn?

  A car is moving with a co wpjm *z;ln.70, mbybonstant 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 cur 7mpy. mw,o bl*n;jz0bve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bobsled to negoti18klnz7;fj y 2vqgoi 3ate a 100-m radius turn at 35 m/s without skidding? ; jznyg38 qvl2o1kf7 i(Ignore friction.)

  A horizontal curve on a bobsle m+hi qmi:e(3kd 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 angl um 4lba4el vu/ tw-j)-+fud)q7km;pfe of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is baphs*) bt-xah+tt+2t rnked 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 i;0e9 qlpna5cqn a horizontal circle of radius 0.500 9nq5pla; 0ceq
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 uniformw.c5i5 r ml)oobtqx9( rate to a speed of 45 m/s in 15 s, moving on a circular track of rawo9. brq tmxc()il5o5dius 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 cons+w twmqv4402.ezva bb/ob o,u ists 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 Earth 2mz0yfm*1- u nch6tih, due to the Moon? The mass of they0u t6mi*hfm2 cnhz -1 Moon is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractiv1-djn*okl4zd+ e wk5 udlfv*.e force between two masses is F. If the masses are moved to half of their initial distance, what is the g fldov*jdzul 5n.d4 k*wke-1+ravitational attractive force?

  For a spacecraft going from the Earth toward the Sun,1;l v el v*b1bcvvx2g*/:yuz dzgy0h, at what distance from the Earth will the gravitational zv y1gcb1l0* ,v lv :2*vubdxe/zyhg;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 v kk5wyl/ 706kvnp 1gjb11rk t$7.4 \times 10^{22} \; kg$ 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 fom*vs goz:unhm k)e2mz/m- b8:r a "space-walk" at a distance above the Earth equal to the radius of the Earth. What imnzv /-shm8g eb :*m :kouzm)2s her acceleration due to gravity?

  The radius of the Earth i;1ca7elu(f +jkk bjjsh1t5 d6s R. At what distance above the Earth's surface will the acceleration o1kb a6u+(1jtj7 5 kseld cfjh;f gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equzcwv. me8ze*ls:xbsh:o4d r r;z68) val to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity4*xe:m e)w o sbv86zz: z.chdlrs8 rv; on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of grf0jf7w37pg qng ) pd:lb*wu3, rsyhy-avity is fjp7,q:pu*lg 3 3rwy fd0wyhnb -7sg) $32 \; m/s^2$. 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 Eartgxhl.3v2reuqcqs r .mvb/g ;b :6(*ivh has radius r. If the object is raised to a height of 3r above the Earth's surface, q:qr3c.; hsbg*ge(rv2l./b mi6 xv uv what is its weight?

  By how many newtons does the weigh0dl 6liofv*ma x6c +a4t of a 100-kg person change when he goes from sea level to an altiv ad0fx o4ai6+lm6*l ctude 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 100 kg ia +)sbfg3i +pvky3dsgf8s, -1m i6v avs at a point 3r above the Earthsv+g s3bka f 1va fg,d)863mviis -+yp's surface. What is the satellite's weight?

  A spherically symmetric g; m 1rpct)vzb41d5dcplanet has four times 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 the surface of this planzpd5vcd)b 1 1;rt4c gmet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie o*;kciqnn;,ngp; 1sji n the same line, with the *n1jsqn gi;;ic;k n, pEarth between 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 -mro:c3c.c zd 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., it just svspsr (l 14.ebkims the surface of the Earth). pslr1v s.4e(bWhat 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 cl jz s 6 0glzlg/h/aq/y917e8d0saduorbit about the Earth (i.e., it just skims the surface of the E8sgsl6e cadzg //90lj0y71zah uld q/arth). 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 orbit 23 nz7f-q q99ghm0 km above the surface of the Earth. It is ognq9fm 9hz-7 qbserved 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 orbital diamet7s-5gb7zy vt,i8ji5t*ljom mer of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupf9cx2r h:054 jzubi-q c(zn vaiter 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 A has orbita -,m0pnefa:r c59j gfyl radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it takeyj,c a:0rn-mpf9efg5 moon B to complete an orbit?

  The planet Jupiter is 4cd z o8pe8yln+j ix*)$7.78 \times 10^{11} \; m$ 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 Sunnvsr4o4 3g8ahcf8i o+lt1:b o82iri c once. What is the average distance from Jupiter to the Sun? (The distance from the Earth to the Sun is f83 v21ogion 8i4cc: siob t lrh+ra84$1.5 \times 10^{11} \; m$.)