Is it possible for an object moving with a cons7 p 2fy:gx*ot-a/jwe otant speed to accelerate? Explain.g:o-a7 y2t ep*j xfw/o

  Consider a particle moving with constant spe-miw ipoh:1 l6c-ph:jblihx5cn/r- .ed such that its acceleration of constant magnitude is always pephh.o- i5b wih:cxj:p 1 mrc -inl6-/lrpendicular to its velocity.

  An object moves in a circular path at)fnaql+:p ;lc a constant speed. Compare the direction of the object's velocity and c ;lqp+fn: l)aacceleration vectors.

  When an object experiences uniform circular motion, the direction of the ac+mnd9j lj3g e ntm/x,,celeration igtjmx/ me 9,d3j+,ln ns

  Consider a particle mo6wgk( g05gjj jving with constant speed such that its acceleration of constant magnitude is always perpendicular to its velocityjj 5ggj06w(kg.

  What type of acceleration does an object moving with constant speed in a circu9viczs5fnip - qml)1 oe+p +1 k+1ial6jw:tnglar path experience?pi5)1 l-wa++zg+n61:ml np iq9otfjks e c v1i

  What force is needed to make an object move inr0jkt8-tv 1ng , mlmb1 a circle?

  When an object experiences uniform circular motionx3ee( drxf3 4kimdl9 fa* c*)rd5gl4b, the direction of the net forac43 (df klx *5edr 3er)bm9dfil*g4xce is

  A roller coaster car is on a track that form 9pn.zvj4 k4qrs 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 for its centripetal acceleration ar.knvzq p 49j4t this point?

  A roller coaster car (5wz tgc*6t gv: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 trgt:gwvc 5 6*tzack at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a verti 04b qo z9ce2dwpuej,,zkq 3:scal dive then follows a semi-circular arc until it is going straight up. Juszbzoe42w 0,u3 c s,epqjdk9 q:t 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 curve oa05ygav0a-/fzr sc. bf 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 speed v. Then qr/ c n k8ftr,a;y8co2 nq/k-qit 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 time?8qnr tr;-/ 8of,/ k2qckcaqny

  A car goes around a curve of radius r ata k0z/edw u,0jr9,lm7 poih 0u a constant speed v. Then it goes around a curve of radihz0,,ro eawi0 j9udlk0 7m /upus 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 curve of radius r with speed v. If the ro 58w jwk2jyxfgd4 ih6n837nikad is frictionl6iw 5nh4 gwkdk 27n fixy883jjess 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 b5;wf k zg u+.muuan wg7*npy 3;w/1gva bobsled 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 smab +/5yvwfa.n; ; zkmp137guu ww ugng*ller radius curve is v. What is the safe speed on the larger radius curve?

  The banking angle in a turn on the Olympic bobsled trac:cw f b,yxgu )zwtau 6-f22q8xk is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "u x,6xtzy2f - f2c8qg uawbw):climb the wall," then go lower coming out of the turn. Why do they do this?

  Is it possible for an object movin6 t szb8*hqgn y*c*lb2 sm;df2g around a circular path to have both centripetal and tangent; l*cmd qyb6 hs22t*n8gz*bs fial acceleration?

  The gravitational force between two objects is pro/hbi h3bnu ; u)-k)gl;uyy 9hbportional to

  The gravitational force between two objects is inver81axz3o3.nubv qrdawo,gf*1tl( 0 x ksely proportional to

  Two objects attract each o+hrrs 1xec .xi3 8omp-br* ma5),nstgther gravitationally. If the distance between their ce sic3 mr +t5hrpr1.n,a)s gx-eb8ox*mnters is cut in half, the gravitational force

  Two objects, with mas +wd dogl9;ce9ses $m_{1}$ 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 v5 bod2wm4ossa1.y o g(:j/a$m_{1}$ 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 gravusuv*s 5*z5kbcz *d j0itation.

  Compared to its mass on the Earth, the mass of an object on th un41tv+ ce*kje Moon is

  The acceleration of gravity on the Mosf 4zfh(twql+ 5 c.g-aon is one-sixth what it is on Earth. An objfcw5gq .szft(+l 4a h-ect of mass
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's sua/ui5f;9vrn d c ahj*t4c4xz3rface, the rocket's weight

  A spaceship is traveling to the Moon. At what pz:m yi +x 1)g7;z8gfvs tw7sq9wepe)voint is it beyond the pull of Earth's gravs eqgizmf)9:v )p v77x;w+ gse18zywtity?

  Suppose a satellite were orbiting 524,w3 qzvc ve2 im6dstcobk*the Earth just above the surface. What is its centripetals5ew4bzo ,v6td22mqv i3cc k* acceleration?

  A hypothetical planet ha+1 25jjjagt nms a mass 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 acceleration due to gravity at tjjmjg1a t+5 n2he Earth?

  The acceleration of gravity on the Moon is kn qbl;t:nx)4one-sixth what it is on Earth. The radius of the Moon is one:;kxt n4)bnlq-fourth that of the Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the8fj / ;a2/q qawjzbhz4vr9tg/ same surface gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the masgaa//;hwjt4z2 b8r9zv qj/f q s of planet B?

  Two planets have the same surface gravity, but planet B has twice the mass of : 12ggnm:+8cz 6tfjxe 7e l(obi oku)uplanet A. If planet A has :m(ogg1j)u f6t7u2:e+kze8 ilnobcx radius r, what is the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) about a u,twzmr 4 /h/wspherical planet (mass M). Which exp wtwz4/,r/humression gives this satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates g4- by+fd7ag rin the same orbit. Compare the twodgrga yb+-f4 7 satellite's speeds.

  A person is standing on a scale in an elevator accelerating downwar)95qtnp0a cgyd. Compare the reading on 9ga q0tp5ycn)the scale to the person's true weight.

  Who was the first person to realize that the planetse sj-u8*m2aes move in elliptical paths around the Sun?s*m8-ae j2us e

  The speed of Halley's Comet, while traveling in its elliptical orbit around th.9hhw7zl+ce jp /jy 0ee pe7hwj9/+. hy lec 0zjSun,

  Let the average orbital radius of a planet b-yya,-g)otdnfhpx ;0e R. Let the orbital period be T. What quantity is constant for alh g ,--od)nt y0a;xfypl planets orbiting the Sun?

  A planet is discovered to orbit around a star in e8fhq ezfb4g1b9, o8j 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 revoluti9 84gbe1f,8 qo jezfhbon of that new planet be, compared to the Earth's orbital period?

  The average distance from th(/q5 b6xw n+4qpp hpife Earth to the Sun is defined as one "astronomical unit" (AU). An asteroid orbits the Sun in one-third of a year. What is q4q+/5iw6 pnf(hb pxpthe asteroid's average distance from the Sun?

State Kepler's laws. zp)ym0 0q/wgw 8lvi8p

  List the four fundamental forces in nature.7yj2 ;mh9ytwq

  An object moves with a constant speed of 30 m/s on a circular track of r6ph9vhdwx ku0xv ;: j1adius 150 m. Whatd: k 1uj w6phxv;xh09v is the acceleration of the object?

  The maximum speed around a level curve is 30.0 kfx 2g/9 sk:aibc0 izv9m/h. What is the maximum speed around a curve with twice the radius? (Assume all other factorsz2svxi9b/ 0cagikf :9 remain unchanged.)

  What is the centripetal acceleration of a point on the perimeters*h:7n r7ci 8 yf)rlcb of a bicycle wheel of diameter 70 cm wchb *cl7n8:irfrsy )7 hen the bike is moving 8.0 m/s?

  A point on a wheel rotating at5q7z b)juk4f ly4rul ( 5.00 rev/s is located 0.200 m from the axis. What is the centripetal accelerf(uzrlj7 uqb54k4)y lation?

  How many revolutions per minute must l2u:f1j 0-clatn 7ztopx1+ jca circular, rotating space station of radius 1000 m rotate to produce an artific ptt0 +j1 zlfj:lcu-27x1a nocial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250 kg. It goes around a 13.7m7* jt4id,/z 59a zstvyq; tol m radius turn at 96.5 km/h. What is the centripetal fora,zj ltoz7t9t*4qsvi 5; /ydm ce on the motorcycle?

  A 0.50-kg mass is attached to the end of y)h h+qq3hpl+a 1.0-m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can w hpylh+)q+3hq ithstand 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 rrb4cnf(/*f me b1 -dkto a strong string and whirled in a vertical circle of radius r. At b4br/c*( nek- rdfm1fthe 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 given by

  A stone, of mass m, is attached to a strong string and whirled in a vertihg(4)-wa)bfy q2cz ow cal circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stoneo42fwc (a z)- whbgy)q's weight. The stone's speed at this point is given by

  A jet plane flying 600 m/s experiences an acceleration of p*:p y1gi(szxo g, )ad4g when pulling out of the dive. What is the radius of curvature of the loop in which the plane is flydo :a( sp)1ipyxg g*,zing?

  A pilot makes an outside cm6//1e) k hthxl: hvnvertical loop (in which the center of the loop is beneath him) of radius 3200 m. At the top of his loop he is pushing1eh)vkn h/mxtl 6h :c/ 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 about seven times his e8u.z mc :-ljk1u-acdweight. What is the minimum radius of c8cdkje z-:u1- . acmluurvature 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 radius horizontal curve wi;smt v (lu8p-pth the tires on the verge of slipping. How fast can this car round a second curve of radius luvm8spt -;p( 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 ik.quj7iv81i of 20 m/s. The centripetal forck8jq.7iui i v1e 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 ate *u,,: 9y*oz0xl- qqfs 0tlqhoglt 0a 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 l l*tft-, u0ql0*zg:x qo,0o9q y sheathe turn?

  A car is moving with a consta ; k7yhnym wy6k)x8zzr5ns*xt(e( c8 ant speed v around a level curve. The coefficient of f8*nzry((8 yxsmkk na ;)x 7zh5yte6 wcriction between the tires and the road is 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 Olympic bobsled to negotig3p)m jj6oh 6aate a 100-m radius turn at 356mp3ag6hjjo) m/s without skidding? (Ignore friction.)

  A horizontal curve on a bobsled run is ban+9:x0ieiaj o oked 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 ofzcp3d3bet wq/mp)8 fl 4-l-ko zfc8 hnvo +:,j radius 100 m, banked at an angle of $45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m i;)muuo.q7hhe v li atw+/l6pgt-6 e.gs 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 stringcg0piq f7- ox9 is revolving uniformly in a horizontal circle of rad0ix o gcq-7pf9ius 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 s-p j4 :ri9t17 k5cxc wcors8darea, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fi5ij94ktp:7xo1ssrdw8r cc c- ll 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 consistmpl0n3rcht/ nw 1k1 p5s 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 Ea kg;q5.bsx ng7rth, due to the Moon? The mass of the Mx;q.g5 7bskgnoon 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 F. If the 8qbm77nbrll l19mh w4 masses are moved to half of their initial distance, what is the gravitational attractive 7l1lhbm7r4l 98q mwbnforce?

  For a spacecraft going from the Earth toward the Sun,qlh ;fvzy1: kvm8 a*c6 at what distance from the Earth wil*k :y6v; q a8vzhfmc1ll 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 i84gd:8zrf ojx s $7.4 \times 10^{22} \; kg$ 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 "sc lr 8/p*zh1uypace-walk" at a distance above the Earth equal to the radius/hpy u1lr8 zc* of the Earth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above the Earth's suuwq9x ot/ ;sat-6/(fl,losf hrface will the a(tl xh6 f- q/uofw;ot,ls/s9 acceleration of gravity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a d 8z*biu,(2 dt6t duz u6op-unkistance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellp, o*z kzdt6dutu6(82binu u -ite, as compared to the acceleration of gravity on the surface of Mars, is

  At a distance of 14000 a4bol7 /vco; zkm from some planet's center, the acceleration of gravity icbl; 7/z4oov as $32 \; m/s^2$. 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 Eae7m s *)z5wk-rdmji z.rth has radius r. If the object is raised to a height of 3r above the Earth's surface, what iik7m5.sre)*jmw-z dzs its weight?

  By how many newtons doesa k2v6qpn,qbtr531hwj(q/f tt /wlm9 the weight of a 100-kg person change when he goes from sea level to an altitude of 5000 m? (The mean rt fb1 t/5whk v2a3qw6/ 9nq(tqj,rmpl adius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of masif gcfqw+r; rm)*04a:aayt /wij+z9ms 100 kg is at a point 3r above the Ea m9ifyw)qa0a+c+ a:4gfj w;*i rmrzt/rth's surface. What is the satellite's weight?

  A spherically symmetriclsopa/l)zezkgf s 2)i; (*b57zvcx /z planet 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 Ea vs2;lc (gl)sxzfb/*k)zi7/5 o apz zerth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the M.avpzist m0(1phd15u gl-a m/oon, Earth, and Sun all lie on the same line, with the Earth between the Moon and the Sun. The Moon has a massh/imgzp.t -dma1a u05 v1ls (p 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 Moonmp7:y ax mq(p).
(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 ca/ 4igw4)8sr7krxr( mi n)yx2sr 0 ooskims the surface of the Earth). What is the speed oi/soyrrm w )r7 r gx2n4s(x8a) 4kci0of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low c(ft x0pcj v+9circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around+vct09cx j(fp the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km above the surfaceqo*1z fgxhgty q,0dn79 3 lkr: of the Earth. It is observed to have a period of 89 min. What is the mass of the Earth? (The mean t7*yq,kdg19gfxh0 lzq 3 ron:radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an or9s5-1 tj,+(usmvqwrv8 t. ahythq 4kibital 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 -kdpq;f 7c/ss 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 orbital radij4hwbdtu;nh798. otix + cn/junonbp62/mq 6us r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to9 26nhnjh7qno/ ;ibmt6 d8w/4nj c+tpu ux.bo complete an orbit?

  The planet Jupiter i+gh+h5o3,duk fmm x4xs $7.78 \times 10^{11} \; m$ 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 a3nr5o+icdpbp5+c 3u:vh2dr 23r* mmii /m knkverage distance from Jupitecmmp:53nk3* b+ i/3umpo ircd2n52rvki drh+r to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)