Is it possible for an object moving with a constant8i4to k 89bpoy speed to accelerate? Explain.tokb9io48y p 8

  Consider a particle moving with nwi c.a7 oeb.*h0si54 xfke*kconstant speed such that its acceleration of constant magnitswh.f i0on 7e5kia4* c *b.kexude is always perpendicular to its velocity.

  An object moves in a circular path at a constant speed. Compare the dire ,h )vh9wyiod:ction of the obd9w)i yvohh,: ject's velocity and acceleration vectors.

  When an object experiences unifobp9cp;q. l+ bnrm circular motion, the direction of the acceleration bpblq n9cp .;+is

  Consider a particle moving with constant speed such that its accupr+p*5o ;wuvle;7k m eleration of constant magnitude is always perpe; ; 5w rp+m*vo7luupkendicular to its velocity.

  What type of acceleration does an object moving with*f0 (s tzs7fw3c0pncx constant speed in a circular path en0sf x3 wtpsf*z cc0(7xperience?

  What force is needed to make an object move in 8*cz17d luv lwa circle?

  When an object experiences uniform c6l48a30pwu yz: nw4ncya 4 qxuircular motion, the direction of the net forc3zwuyyl n4n0xaa :c uq6 84pw4e is

  A roller coaster car is o 87c0( :rtymbh9bs nw5e/wag;zb d6dqn a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top of the loop, what is the minimum value /;wzc 7qh 809arnmwsbdt g6d(e:5bybfor its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track 3x +w2(d(vzo+g(ou pu:exml3xkk f( jthat forms a circular loop (radius = r) in the vertical plane. If the car is to just mai:dmx+ 3w2((3pk z(lof gxx+jok(veuu ntain 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 i3bd9 mcc:sv ,yy:h5oo yf;x;arc until it is going straight up. Just as the plane is at its lowest poii y:oy;vyo;xhb c53:9c sf ,mdnt, 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 z ;ustzahygrr- a+*3fn*b(5 gof 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 constant sra o4-+wxah;c 26su dqpeed 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, compare;h+ s-ar w26aqucxod 4d to the first time?

  A car goes around a curve of radius r at a-r rxl, o7yq(7pv d6xk b)zqf0 constant speed v. Then it goes around a curvr7p6 q0 rod7-xbfkl(v) yxz,q 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 a banked in5np m50n4n xh4j;o+-kd2wmqwb6e hcurve of radius r with speed v. If the road is frictionless due to ice, the car cdmmnjwp-5n;o2 n hk 40eqi+ x 54bwn6han 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 abs+q g: a-*t*cq cp q*s4u0mhtt the same angle, but one has twice the radius of the other. The safe speetsp a c4m sh+q-gbq*:*c 0tqu*d (no friction needed to stay on the run) for the smaller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled track is not constant, bu i2ldqpkq7-e fofn-88t increases upward from the horizontal. Coming around a turn, the bobsled8oi2l- 8pkq -eq df7nf 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 movingw7aq03s1. ; n y.1 2mdoumnpv,eohnqf around a circular path to have both centripetasw dpqqnm,ym.;vn fo1h 1o.e2a73 0 nul and tangential acceleration?

  The gravitational force betweenmv h:qhl+lnbz7kox * 8bya:a,m0f h 94hx-kw. two objects is proportional to

  The gravitational force between two objeyuw0xg 3z0g2w cts is inversely proportional to

  Two objects attract each other gravitationally. If the distance between trkk6 y f8n+f8rheir centers is cut in half, the gravrfryn8k8+ kf 6itational force

  Two objects, with mat n0qxnu t*4b+sses $m_{1}$ 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 masse5bi8 zrr4qcie1 n 94pts $m_{1}$ 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 univerp8a-l f2d3wnm 5y 3qm f0e6fthsal gravitation.

  Compared to its mass on the Earth, the mass of an object on the M kgni(zd,8xdyrm7k43bv,y 8w6; f9ajep: ytg oon is

  The acceleration of gravity on the Moon is one-sixth what it is on Earth. An ob as t(27qsv*o2rj qrjyw ,579;icsk iojero9*jq57 sicqt,i7sso ar w kj22(y;vct of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's surface, the rocket'sj.1ekkh :f/t o0ae8lz weight

  A spaceship is traveling to the Moon. At what point is it beyd.k 5wko,,jz5ql jb9a1 z1 llaond the pull of Earth's gd.kwl9azkql5 l51j ,bja1 oz,ravity?

  Suppose a satellite were orbiting the Earth just abov bxqw 3-9rsbp:p (t2uoe the surface. What is its centripow3xs2q-(:br9pp tub etal acceleration?

  A hypothetical planet has a mass of half that of the Ea uc1okm2vu,4 q bs y5sad;b16erth and a radius of twice that of the Earth. What is the acceleration due to gravity on the planet in terms of g, thes ye6 udam;v5 u,b21okc4 bqs1 acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is,llqrhwmp,cu p4 l85- one-sixth what it is on Earth. The radius of the Moon is one-fourth that of the Earth. Wcm qu h 8-wpp,lr5l,l4hat is the Moon's mass compared to the Earth's?

  Two planets have the same surface gravity, but planet B has twice the rv5,phxf7y/ 7 1q dwywfx-awz/adius of planet A. If planet A has mass m, what is the mad7fhpq/,/w71w 5 xvfzxwyy-ass of planet B?

  Two planets have the same surface gravity, but planet B has twice t, 1 4:vnh:vx.fu4 g;laj qsk4y,geijxhe mass of planet A. If plx yi,u ,j; 4. ::skx4v hvl4jqngef1aganet A has radius r, what is the radius of planet B?

  Consider a small satellite moving in a circularb m8cn p62f,;:hkk onf orbit (radius r) about a spherical planet (mass M). Which expression gives this np8 knmcbfk6 ,fh 2o;:satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in the same orbit. Cmy *nvc)*cpvo/.w x ;yompare the two satellite's speedspyocn.xw/)mv y* vc; *.

  A person is standing on a scale in an elevator accelerating nc3upi(vb(wg . ,ovmw go*l.66qclw(downward. Compare the readingw,cwmo6n .p6v *3(iqov. gb cw g(lul( on the scale to the person's true weight.

  Who was the first person to realize that the planets mosdef3eb ,yjh;3; s8g dve in elliptical paths around ted3 ;ysbs3,8 gd;ejhf he Sun?

  The speed of Halley's Comet, while traveling in its elliptical orbit arounqrr gjbvn,9-z*c ix8gko ,- n5d the Sun -i,*ck,nb5j9 r8zov-ggnq xr,

  Let the average orbital radius of a planet be R. Let the orbital 3z.xj- c o/g7x1pphgy i8m(stperiod be T. What quantity is constant fortg gx 3x.1z(yh8 -pcp7oimj/s all planets orbiting the Sun?

  A planet is discovered to orbit arou*c8,cc),gx4t dl7.uyfvep scnd a star in the galaxy Andromeda, with the same orbita c ),u7.*,peyctx8v4scfgcdl l 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 period?

  The average distance from the Earth to the Sun is defined as oysh q5)htmd2+ne "astronomical unit" (AU). An asteroid orbits thh )hmd sy2q5t+e Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.xg pq*n,ge 0 :zvqjt(p 8)+v d)g2jgjl

  List the four fundamental forces in nawmw f2n**oqrf ht0,m6qeg*2 m5on p+ lture.

  An object moves with/cvv11q 6il3chz khv0 a constant speed of 30 m/s on a circular track of radius 150 /cv0h3z1k q 6 hvlivc1m. What is the acceleration of the object?

  The maximum speed art/) xuz+woqr,ound a level curve is 30.0 km/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors rem ou )qrwtx,z/+ain unchanged.)

  What is the centripetal acceleration of a point on 7ftzx9jk 3fwvn2q 2u 8the perimeter of a bicycle wheel of diameter 70 7u x vtq 2w83fnk2fjz9cm when the bike is moving 8.0 m/s?

  A point on a wheel rotatingl5kaub; yp i-xw/d;3ifxiv 72 at 5.00 rev/s is located 0.200 m from the axis. What isu5k;/x3 i iv7-d2li fpwb ;xya the centripetal acceleration?

  How many revolutions pf73 ,n 4c+y ;c ygoxyfibn0 hd7r1wuw3er minute must a circular, rotating space station of radius 1000 m rotate to produce an artifi7if3cy 3fwgy1dr+hnw ,x;0c 7 oun4ybcial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes arouobzj .-amw l:1nd a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on thej1l:am wz -o.b motorcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. The system is whir+k a oyqgd+ sy-y;yy z kucw++9pjzwsv,(:m+5led in a horizontal circular path. If the maximum tension that the string cy:wwc+jy-syqo uzk +p dv z ,(5a+ygmy9+;k+ san 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 whudg;or9e u/4iv. iv6e irled in a vertical circle of radius r. At the exact top of the path the tension in;di/ vug i4evor9 6.eu 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 string and whh.wa,n-,abah-s 4 h rsz6qdj7irled in a vertical circle-,764a.hh j absdwz-n,q s har 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 this point is given by

  A jet plane flying 600 m/s ajkfz1 vm6w8. experiences an acceleration of 4g when pulling out of the dive. What is the radius of curvature of the loop in which thevf1 w6z mk.8aj plane is flying?

  A pilot makes an outside vertical loop (in which the qpfjzxbv4030;u*jry + b (gp4kr 8xxr 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 weight. How fast is he goingxvbjz;gkxypjxu0 q 4b+f08 p34* r rr(?

  The maximum force a pilot can stand is about seven ti8s wiyzxevjm *.am5y:(:w 2afmes his weight. What is the minimum radius of curvature that a x 2sa jw8::y mwav5yie*zfm (.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 radius horizontal curve with 5gm:ye :jl-ac the tires on the verge o5ml :yajge- c:f slipping. How fast can this car round a second curve 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 speed of (tzeq,:oxsea 0skr :-20 m/s. The centripetal force provided by friction ieskat:r oq-:0(x ,ezss $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of radius 50 m zx1xp)in6yw b3p+ w bjn/5 5juat a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for the car to make the t 55+bzpyujxwnb)31px/jn6i w urn?

  A car is moving with a constant speed v around a level curve. The coefficien4kn,q+0u1ca8vi j f jet of friction between the tires and the road is 0.40. What is the minimum radiu0 acuk1qjvnf ij+e, 84s of the curve if the car is to stay on the road?

  What minimum banking angle is required for an Olympic bz. gy,h( nhza8.ae(jaobsled to negotiate a 100-m radius turn at 35 m/s witho nzaajh.8.(g,( eyhza ut skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is banked at 6 xlbjgt6)mu ,u go p1vmf4p8)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 h*37ikjx f0c nhv1; gnat an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m(ye53tvxepuga sf)(+yf;c- c 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 horizontal cly:3fbcq6 l*x ircleqc3f 6bxlyl:* 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 rateme-3y9 qqitap9e( x ed i,o;:x zqcq34 to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (onapt;3z qc-i od(xeqiq :e9ex4ym39q,ly 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 protontz4yz vxij23- h v4oq* 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 persl4 4su5oz,jxson standing on the Earth, due to the Moon, lo ssxu5zj44? The 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 attract/i8n6wa3s r- bc ttl0eive force between two masses is F. If the masses are moved to half of their initial distance, what is the -abtcrws3l/8et6 0ni gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at obapt;m7ye1w4u9 t m4 what distance from the Earth will thm1t4uom wb;4at97py ee 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 2l3/3 kwqr+t0(px e+dgmjg yn$7.4 \times 10^{22} \; kg$ 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 fob 3j:o;3prz7bo 4ywuqr a "space-walk" at a distance above the Earth equal to the radius of the Earto7ur:oyj3;wb 4qzbp3 h. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distanceq+d 8sym0 l8ce above the Earth's surface will the accele8lqdscm0y+ 8 eration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a distance .w tf2dg+khvsz-)v ,t above its surface equal to 3 times the r) sgk vd,vfth2 tz.w-+adius 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 km from some hadgz6v2), g )4io oiuplanet's center, the acceleration of gravity oaug2 h6,o) d4i)vi gzis $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 Nwe( bf wvlg+b-/3t3gu 13pxfb on the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r above the Eavublxe (p 3-bw f3+g/f31tgbwrth's surface, what is its weight?

  By how many newtons does thtny z(t7 hqz 7xu4x23he weight of a 100-kg person change when he goes from sea levey 77th(n3tq24 xuhx zzl 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 100 kg is at a point 3r9l.jnfro,t0; sfa-m a above the Earth's surface. What is the satellite's weigal. f -09,soat;jmrnf ht?

  A spherically symmetric planet has four times 1mb0t 3/t9eqb )gnkka the Earth's mass and twice its radius. If a jar of peanut g1q/ knb3a9k 0mte) tbbutter weighs 12 N 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 sam* c w nn a+(yer4: oum:.0dv4gabd;were line, with the Earth between the Moon and thnbg:dom*aw.4 nw u rd04+ v :rea;(cyee 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 9 33xsy. ycyj7w rh/xgMoon.
(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 circul9 d;pe -vlczc0ar orbit about the Earth (i.e., it just skims the surface of the Earth). What is the s9cc 0d;z vlpe-peed 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 Eal:oqudz. m y-5ll1au/er:e f0rth (i.e., it just skims the surface of trquyof5ll z -:ul a/1.e:edm 0he Earth). 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 2:f )d bqn*i.ir30 km above the surface of the Earth. It is observed to have a pein *bir):df q.riod 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 o:d a70*(y.v5yn7 ;z2wiwodswczh;*s b kbzmhrbital 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 orbitslp2 1 k5pbz6us 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 plane 9xcvuf4 2s7s,9ieyd0/ai6cj)ndv cqt in nearly circular orbits. Moon A has orbital radius r,0,y9 j7/9fvi 2id cs asec6cxvqud)n4 and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to complete an orbit?

  The planet Jupiter isragx8r k78vng/ fn)s8 $7.78 \times 10^{11} \; m$ 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 tp3 -ocg o7mlk6he Sun once. What is the average distance from Jupiter to the Sun? (The dista -7o3 ogmpk6lcnce from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)