Is it possible for an object moving wdvzo+ur f37 .oith a constant speed to accelerate? Explain.o7 3ord vuzf+.

  Consider a particle moving with constant speed such that its acceleration ox qfwh0:f: trd,*( sr lvo(e+of constant magnitude is always perpe fq+lr:ov f*:ter h(,os w0xd(ndicular to its velocity.

  An object moves in a circular pa5d ul14yw4 -9uqx o9tr1howj*6hmw ngth at a constant speed. Compare the direction of the object's velocity annu 6 w xmh4d4uyoj9ro whl5t*1w9q1g-d acceleration vectors.

  When an object experiences uniform circular motion, th alz*b;zb, pp,e direction of the acceleration ;apbl* zb, pz,is

  Consider a particle moving wit3-v,0x aokea fh constant speed such that its acceleration of constant magnitude is always perpendic0e- kf3vx,a aoular to its velocity.

  What type of acceleration does an objectm 8we wy (m dujwe8cy)8;h1u5a 9m2kxf moving with constant speed in a circular path exper u )1 9f8dyxw25hmu8kyew(mjmeaw 8;c ience?

  What force is needed to make an object move in a ci0jm)zuv f, w+arcle?

  When an object experiences uniform circular moti;f2pd 7e2 z pi3o,elmlty2vr9 on, the direction of the net forl edy7,2tmol ir3vp2p 9;fz2 ece is

  A roller coaster car is on a9 wp5ky0-zpsz track that forms a circular loop in the vertical plane. If the car is to just maintain contacyz 9pw5s 0zkp-t 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 tr co+ys(0kbu09yp bu9 23 qailfack 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, whyu99a2cy(s0b+l qkb0 fo3pi uat is the minimum value for its speed at that point?

  A pilot executes a vertical dive then follows a semi-circular ahccku;:7x/ x;cme+i)1 ojpi2y;mgbxrc until it is goingu7xycm x1keigjh m +;; ocbpi2);cx /: straight 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 ch 5c *s12yrvszr)ktoua58cl6 urve of 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 cons5nzv(.h a0j)tlljz .p tant 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, compared to the first tlj v)lj .a (t5h0.pnzzime?

  A car goes around a curve of radius r at a constant speed v. : zc5 oirxs)9m Then it goes around a curve of radius 2r at speed 2v. 5 9: )smizorxcWhat 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. jg.r q; butpw)*0e n7nIf the road is frictionl0; )tj g*b nr7epw.qnuess 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 on a b v7 z yl oimw2+ef:rkl(62kjv(obsled 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 radius curve is v. What is the safe speed on the larger radl rw(vi:(7k2+jk2vfzy6 ml oeius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant, be zdsz4-b. uz,rt3e j9ut 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 zj4 ztdz e,rbs.e9u3 -do they do this?

  Is it possible for an object moving around a circular path to have both cenksg2p m-/*oojjk)x+s( 3f jnqtripetal and tangential acc ksj(gp23 nsox jmf+/) jk*-qoeleration?

  The gravitational fouc-0nk0c si5d a0 klbc5 9ere-rce between two objects is proportional to

  The gravitational force between two objects is inversely proportidet /2m:p(ru monal to

  Two objects attract each other gravitationally. If the distance betwee nibk f5:sz:1on their centers is cut in half, the5bzfn::o ski 1 gravitational force

  Two objects, with massf5i2c :a1wcj(bbe*ewf tg/c 4es $m_{1}$ 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 massuw4x+rm-;a 2. pwh)hz/ff yvaes $m_{1}$ 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 gravitatjoe , ,:o8lm.tsdy z1pion.

  Compared to its mass on the Ea9,b vckb2eot 8rth, the mass of an object on the Moon is

  The acceleration of 2;ntmqjet7 l.sq:tl-gravity on the Moon is one-sixth what it is on Earth. An object of mas7;lsj e qq.lmt2tt-:n s
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Ea:3ludre z-c ha:zo3va3 1fvk2f1qs 6vrth's surface, the rocket's weight

  A spaceship is traveling to the Moon. At what point i78u l4p) czdoq.v60vu(sfv eys it beyond the pull of Earth's grae48) 07op . uufqs vv(ylzvc6dvity?

  Suppose a satellite were orbiting the Earth just above the surface. Wekx9s5 r+ jds;-:m jug+pbzn1+vmh,s hat is its centripetal accelerati j spbz+g,hjxvkd-1ms5n;m u +es :+9ron?

  A hypothetical planet has a mass of half thaz3p vgyqj0 *2tt of the Earth and a radius of twice that op*jtgq 032zv yf the Earth. What is the acceleration due to gravity on the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on thpudb pjy( u (gf9:x,j)hhb)4ve Moon 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 compared to the4,u j)pghxvd9pu:b( b ( f)yjh Earth's?

  Two planets have the5-tlv zxsj: / c/cb angt9a7r. same surface gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of plane/tlsc5 7 / r bxn-9avgczjta.:t B?

  Two planets have the same surface gravity, bu)qrnt.3 6q spht planet B has twice the mass of planet A. q n3s.6thrq )pIf planet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a spheric cvj4kf2f0;-ty8sdra h (b/k jal planet (mass M). Which expression gives this satelli (r4kys-c028ftj;jkbf / adhvte's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates invln266omuiq- the same orbit. Compare the two sm2 vo-ul q6n6iatellite's speeds.

  A person is standing on a scale in an elevator accelerating downward. Cwlkb *z-017wl)bty/ 1hv2i/ kaohzbdompare the reading on the szkthbbaw1ldz/o) 2v li-hy7 /0bk w1*cale to the person's true weight.

  Who was the first person to:1fg gj;vqwb :ue;x) e realize that the planets move in elliptical paths aroun :egjxvw; e b:ufq;g1)d the Sun?

  The speed of Halley's Comet, while travehaed/6ptzr /+ 5(tkaw 1ty*wyling in its elliptical orbit around the S/ 1d+ ayz*t yt/wpe(thw56 rkaun,

  Let the average orbital radir u6nz(:adj ih:e; uy+us of a planet be R. Let the orbital period be T. What quantity is constant for all planej ;y 6ruduz +eh(:ai:nts orbiting the Sun?

  A planet is discovered tpxbnhgkj- 7 ae.w3+m(itb3b4 z( e q9so orbit around a star in the galaxy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star s(xhb q m j.aw (9gi+k4zte3e3-bpb7nhas 4 times the mass of our Sun, what 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 d/jy) or*u9zkmd t: k;wefined as one "astronomical unit" (AU). An asteroi/dryo:kzm tuw;*9 ) kjd orbits the Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.1g /6qdakoz1q

  List the four fundamental forc v2: vwhy81qtkes in nature.

  An object moves with a constant speed of 30 m/s on a circular track of p5gwe jhyi5wo;l u59*radius 1505g5y j*lo5w9piw;eh u m. What is the acceleration of the object?

  The maximum speed around a level curve is 3x:w og7p+gkpe-u k/o 30.0 km/h. What is the maximum speed around a curv/ o 3xug-:gkopep+k7we with twice the radius? (Assume all other factors remain unchanged.)

  What is the centripetal*8; qa myrvma7 acceleration of a point on the perimeter of a bicycle wheel of di7vq aay*rm m;8ameter 70 cm when the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/sv; t2h ara3am1dk3c-a is located 0.200 m from the axis. What12cr3m-k d;aath3a va is the centripetal acceleration?

  How many revolutions per minute m8j wc qi8gfv*;ust a circular, rotating space station of radius 1000 m rotate to pg ;wq8* v8ficjroduce 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 a yt/.m4s pgkh0t 96.5 km/h. gyshp 0k4./m tWhat 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 whi1o6w mth uzmnj/y4(i 7rled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maxim t71mn/hw 4oimz jy(u6um speed of the mass if the string is not to break?

  A stone, of mass m, is attached to a strong string and whirled in a vertixrwesjk496r6h.l (/ erurw)s cal 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 point is givershu /6rw s9l)x4r w.k6eje r(n by

  A stone, of mass m, is attached to a stron .j zk9 jm1i6(eq .z8rc0cb2cb me5dhug string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the string is2cccj umb(.hzm .z6ji 5d01 kb re8e9q 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 4hl5woil k 3i)uz/*n)bg when pulling out of the dive. What is the radius of curvature ofi)lzhul/b5o *k)in3 w the loop in which the plane is flying?

  A pilot makes an outside vertical loop (in which the center of the loop isdkrgkea t.1e8.57j+cx6j z n k,gcj(x beneath him) of radius 3200 m. At the top of his loop he is pushing downz nk,jjx ca 16.r(.gc7jkd5g+8teex k 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 sev ,) zrr()qxd4riorxv w;)qpnv2b+r: gen times his weight. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical di :xogp2wrrzr(4,qv vdxrq n;+b))ri) ve, can tolerate at a speed of 250 m/s?

  A car traveling 20 mg dkpaf/oa m/h5o (;e7/s rounds an 80-m radius horizontal curve with the tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume th(mdg/eo kfahao57/ p ;e 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 speed oez*bm ;csz4* zkjg,f jnt*m8 *f 20 m/s. The centripetal force provided by z *s*k*bem48j ;,z gcfnmtzj*friction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat cur*bw7 6+ s vxgfnoc-9k-7ffb uyve of radius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between thefxw-ffn7uv - 7s o*cyg+6bk b9 tires and the road for the car to make the turn?

  A car is moving with a constupst23mhc 38 tant speed v around a level curve. The coefficient of friction between the tires and the road ittch28m us 3p3s 0.40. What is the minimum radius of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olymp;zs.:vnm0 (jpkey/ 7ko ew*m/g0 x nsxic bobsled to negotiate a 100-m radius turn at 35 m/s without skidding? (Ignore f0/egssox*7:; jkxw/k mz (nypne v 0.mriction.)

  A horizontal curve on a bobsled run, yi3so/4rsfa 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 ms7 (jvaktx3w/ i qb21r, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 t9 g7x5evps s:uad:ik; td4 5.cq1 ridm is banked 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 in a horw : p)gogm qz:7hekwhp3u+a 50izontal circz whpe)g uwmo :7gh5p+: a30qkle of 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 car accelerates at a uniform ratf e3vx/qha1s i2wu8cvxe) 24d y/2hf fe to a speed of 45 hwa)hfxe/3e v2vfx1sc284iqy / f ud2m/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 consists of a p6:-.pbcs9 ts, x f2t wrm-v)8yormroqroton 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 o y*l45exi4mj+m5kz qrn the Earth, due to the Moon? T *rj5emi54ymxkq +l4 zhe 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 betweq3 ewq,exb,c+a (*bh5c6ae jnen two masses is F. If the masses are moved to half of their initial distance, what is the gravitational e, ncq wbxa3j5b(h +,eqc6a *eattractive force?

  For a spacecraft going from the u2azu5 r3d ta/ w8b:iuv)f 2vgEarth toward the Sun, at what distance from the Earth will the gravitational forces due to tha: 2f3 tuu )va2/wuz rdig8bv5e 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 rrq1/a0 ejf ybh2t1h 1+fahv4$7.4 \times 10^{22} \; kg$ 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 above 9qe mwoz,h(8ft u 6xi2tw z8,ythe Earth equal to the radius of the Earth6hx8 y q wezt,t89w2u,fmo z(i. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above t.gdt l(.gp j6zhe Earth's surface will the accelt. p .6gl(gdzjeration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance above its surface equal to 3 times thfb z/pl ;f)vt2u eii88e radius of Mars. The acceleration of gravity of the sate;i/b2)f lite88z vup fllite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 km from some planet's center, the acceleration of gravuvf s(zv)t04u ity i4v(vuut sz) f0s $32 \; m/s^2$. 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 ru9 es3imo ws s/bcx.4pg/pm3: adius r. If the object is raised to a height of 3r above the Earth's surface, 4 wc s:p. sbpx9g/emmi o3u3s/what is its weight?

  By how many newtons doiqatq2l3yu5h0 g6 -aees the weight of a 100-kg person change when he goes from sea level to ai0-egh qt2y65l u aq3an 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 100 kg is at a point 3r above t,,k nuel+6xm+7y)dec 7njovp he Earth's surface. What is the satellitnkd6o+mun ,vp7 j+l7e) xc, yee's weight?

  A spherically symmetric planet has fourdps :j vl38iga s* d8rplc-1x4 times the Earth's mass and twice its radius. If a jar of peanut butter weighs 12 Nslcrgl ij vad:p8 p8s-3d4 x1* on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same li h*vv/- wp):h/ifdvl8j f)ak qxaq.u(ne, with the Earth bet dxah/up:8 .fi(jfvqqkvl*h -))awv / ween 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 dl:dp.t wjc(x*vy) ,r transported 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 the Earth (i.e., it just skims :yrnvl6wy 3c4 the surface of the Earth). What yy3 vr46ncw:l 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 just skims ufrg6x g3z nf)c;3u db,j*5nqthe surface of the Earth). How long does it take to make one revolution around the Earth? (The mean radius of the Eajbz,)3 cnnfg3ug* xd5 6quf; rrth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular o jwl+os 2)-tlurbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean radius of ojslw -ut2)l+the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has ,z)69 2elj fknts1l rvan 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 orbits the planet with a radius6u2ck,zr+ b9pira uliyq-/i -:w vre : 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 cn)s npg;(b9msircular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A tang);9(ns bps mkes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter is yorhxv/ ab-)6ui8(m t$7.78 \times 10^{11} \; m$ 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 mn*kh .hid-r,h gy00mlvm v02 the average distance from Jupiter to the Sun? (The distance from the Earth 0mkh2-ml i0hyvr*vn .gh dm0,to the Sun is $1.5 \times 10^{11} \; m$.)