95.02: An object shown in the accompany: 7adug:bvv (.grt.jd ing figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the in.vtra.gv ub7d ::gdj(stant shown?

  05.31: A child is belted into a Ferris Wheeg1)dfn o8bpe a +hr)e-b d-*npl seat that rotates counterclockwise at constantn*rh+e p bf)-1 b)ogp8da-en d speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a n q11/ k +zoi es0ybd eb6ry3m8d3z8mwcircular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular path from point P to point Q. Point Q is exactly half-way around bqmz3 i8zwr0edo+/yekm d1bns1 863ythe circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant spee.e bf fo6js+hsq,7wk*d in a counter- clockwise d+ *he 6kwofsqj,b7.sf irection. Consider a time interval during which the particle moves along this circular path from point P to point Q. Point Q is exactly half-way around the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant speed around the vertical circle hm7xnqjki 74wn i59q.ga5y c *shown. Which arrow best indicates the direction of the object’s ink 4* gw5.9ima 7nxcj7nqyhi5qstantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a str+,mek)d u.g ) xt7vjkming counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the twirling mass. If the girl needs the mass to pass through the point labeled P ink)jtxmk )e, gvu m.d+7 the figure, at which lettered point on the path should she let go of the string?

  15.23: A car moves witrk pp +qyw5qd ww+b/89h constant speed around a horseshoe-shaped path as shown with the arrows in the figure. qpb+q89rw py /ww d+5k Which one of the following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a/lofjbvxo *6mn , vhe73 fk51h simple pendulum that is, *onxbl6jff1e7ov hmk /5h3v released from the horizontal position at rest. At the moment shown in the diagram with $0^{\circ} < \theta < 90^{\circ}$ , the total acceleration of the mass may be directed in which of the following ways?

  03.19: A heavy (2.0 kg) point-like object rests 2.0m from l,uj9 zm 9av1zdye /ns:3tnj8 the center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5.0 seconds. The coefficient of kinetic friction between the object and turntable is 0.50, while the coefficient of stj mn918 9:e/dz ,autvszn3jy latic friction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net forc7cbktj .(8cw 3v) uhfqe is necessary to keep a 1. 0 kg puck moving in a circle of rh 8qj7vc bu3w.(kc )tfadius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g) on t58q/ ilrlx7ex/kb)4btbodj4(b , p j qhe end of an 80-cm string rotating at a constant rate ofx54jp(qb/8 tbo elb x)b/kj i,4d7qlr 4 times a second?

  09.24: A point mass moves alon33m:,s*c i)kgd1+tg jt vr tfbg a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J.1d: ,v t s+3 tcmfrg3)ikb*tjg What is the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 wd l sy* mb ai46b6 ohsjpt/9q;6c73fjylwd ,)m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figurepj m ys36ayoib;wl t/q bcd4j lw)7sf*d9,h66 to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniformqtyp ,6gyd+yop ln :*+9w /pev circular motion. Which of the f:e*,+9d lqynpp/g+tyop6y wvollowing statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a st::f,z (0kiu4ublm a oqy6 aq3cring and whirls it around in uniform circular motion. The radius of the circle is r, the speed of the mass is v, and the tension in the string is F. If the mass, radius, and speed were all to double the tension required to maintain uniform circul,aq :lucyi6a3uq 4(:kof bm0 zar motion would be

  07.22: A mass m is pulled ou9nxa z,a +u;cytward until the string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings through a circular arc. What is the tension in the string yzn, ac9x;+au when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the rightal+m; )lm /ujd. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The driver of the car umdllm)j;a +/ is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of uk p4- ,diyr07l:ujn vmj i60ftqn9 p412.0 m/s. At the very top of the hill, the shape of the road can be approximated as a circle with radius 25 m, as indicated in the figure. Whijip9r744kmy jv pi:t qu6dnnuf00,-lch one of the following choices best represents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is mov a:eoh n)3-pzab:0mzling in a vertical circle at constant speed. The magnitude of the net force on thz:- 0:znah albmp) e3oe sphere

  11.47: A simple pendulum of length Lhasa point mass M released from res5c(bx7l gezygqkd ) xjl2,p;9t from the horizontal position shown. In the absence of air resistance and friction, the mass swings through the arc of a circle. Let T represent the magnitude of the fo2z;xxdj)e5 c9 gg(k,qbl7yplrce from the string on the mass (tension), G represent the magnitude of the gravitational force acting on the mass by the earth, and F represent the magnitude of the net force acting on the mass. Which one of the following choices describes the relationship among these forces when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simple pendulum. The mass is relex ,l,uncx/:/,m hx lndb,i.g fased from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude of the tension in the string (T), the gravitational force on the mass (W), and the net force acting on the mass (F) nm c,xb,/f / lu,i:g.dx xh,lnwhen the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopp /zx2wpx)i2 l 3n/, r3te dedbdni79deer moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what happens to the speed v, and the frequ e 32)b zpx/ddt/,923w x7nlired idneency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to an id ;tb.e6eim. mneal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this location by applying a 10 N force. The spring is brought back to equilibrium and the mass connect eb.6et.n; mmied to it is now doubled to 2M. If the spring is extended back 30 cm from equilibrium, what is the necessary force applied by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant s oghjozjo+guy zxgj:47,- u99u ;*dgypeed of 3.24 m/s in a vertically-oriented circle of radius:oygg4+gjyjzj*9 uod-gh9 x7; ,zu ou 0.75 m. What is the net force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coinsx 8u*46uqykqx-sz8 bu (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and ts* 8-yx 86uuxk 4bzuqqhrough its center. The distance of the coins from the center of disk is related by $d_x=\frac{1}{2}d_x$. Which one of the following choices correctly identifies the relationship between $f_x$and $f_y$ , the frictional force on coin X and on coin Y, respectively?

  15.40: A 2.0 kg mass is connected to the end of string and moves about the st h7 s btxfve65cg ka.86u8 hgdzde9r43 e82zstring’s fixed end in a conica ree 87xg95ze as28u8.zkshhv3c6tdb46df tg l motion with a constant speed of 4.0 m/s. The string has a length of 2.50 m and forms an angle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular motion as shown in the figure. The b9+srr p-q(zvt rotm,d55wp*v1 q -hnstring to which the mass is attached has a lenrhmv,r9npbqp* qow5+s dtvt1-z r(-5gth of L = 3.00 m and forms an angle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mass 11.0g is at rest 30.0 cm from a hc1jyh +. 7,njyzncr1korizontal disk’s center. The disk starts to rotate from rest about its center with a constz71 , ync.hj+1nk yrjcant angular acceleration of $4.50 rad/s^{2}$ . What is the magnitude of the net force acting on the object after a time of t=1/3 s if the object remains at rest with respect to the disk?

  10.35 A point object with mass M = 2.0 kg is attached a distav0ag57t7zx axw;x(zsf n 3c2 ence R =1.75 m from the fixed center of a disk as shown in the figure. The dc 7exz n fxxv0w;sg3za(5a 27tisk starts rotating from rest with constant angular acceleration $α =5.00 rad/s^{2}$ about an axis perpendicular to the plane of the page through the disk’s center. After how much time (in seconds) is the tangential component of the point object’s acceleration equal in magnitude to the centripetal component of the point object’s acceleration?

  16.39: An object moves in a circle, startidcs 1z, r/e8xcng at the top, with initial speed 17.0 m/s. The object’s speed inczre1,ds8 x/cc reases uniformly until it has moved counterclockwise through an angle of$55^{\circ}$. The average acceleration for this motion is $9.8 m/s^{2}$directed straight downward.
What is the final speed of the object?

  16.40: An object moves in a circle, starting at the top, with initial speefmbe-6-khrdx sq y(i :mk:x.d,j:7nz d 17.0 m/s. The object’s speed increases uniformly until it has-fnrxk,.-e :b:hms : m7kyixd q6zd(j moved counterclockwise through an angle of$55^{\circ}$. The average acceleration for this motion is $9.8 m/s^{2}$directed straight downward.
What is the time for this motion?

  17.38: A small 2.0 kg block rf+r z qfk1sjiz7zfb+ iw .0:,oests at the bottom of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest point in its motion, it moves just fast enough for the block to remain in place in the buc:1jkszw +oz,7bffi.fzri + 0q ket. When the bucket is at an angle $θ=30^{\circ}$from the vertical, as seen in the figure, what is the magnitude of the normal force (perpendicular to the surface) provided by the bucket onto the block? Note that the direction of the gravitational field is indicated in the diagram byand that the block does not touch any sides of the bucket aside from the bottom of it.