95.02: An object shown in thet.9ik pm9a( +m5bhaih accompanying figure moves in uniform circular motion. Which arrow best depicts the net force a 9(b.ami p mhi9hkt5+acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates countex8kgjfvx4mb r92 1hig0:mcu:ie47 u urclockwise at constant speed at an am :4 g2 bijmmux1kgeu9:v4ric8x0f h 7uusement 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 circular path atq h f r)y .(;(46qm(loxjl6wyvsnje)n constant speed in a counter- clockwise direction. Consider a time interval during which they s; .jfl()4)vrwy6oq(qn(l m6exh nj 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 velocity during this time interval?

  08.15: A particle continuously moves in a circular path a jhl:djj.pp 1hp8(l 8lt constant speed in a counter- clockwise direction. Consider a time interlljp p(1dhjh lj.p88:val 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 veyuhvylrjy (uo3 ;fh w;h+37q4rtical circle shown. Which arrow best indicates t3jhhov(7+ fhyuy rqy3l4;;uwhe direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of/ v9 lnvor 54k)ubtd:mrv4 wa8 a string 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 mw:amo44rb)ltkr n /u59 d8vvvass to pass through the point labeled P in the figure, at which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speed around a ho:y3.m1;4mhemi,x z f+qfzh s mrseshoe-shaped path as shown with the arrows in the figux e m:fyf; 1mhmh,sq 3+z4zi.mre. 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 Mooj::eg*h l kzo,n perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the*koz ,ge:ljh : 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 objqj8a+)vdkd -w *god /nect rests 2.0m from 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 bwddo8/) q+adv*gj n-ketween the object and turntable is 0.50, while the coefficient of static friction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force isimgkcofra5pugr0 ,6 2gd i0g j4c3+;j necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?gi fr 0+ockg2 u;crjgajp34 ,m0gdi 65

  05.03: What is the centripetal accelerationht*nz-q-idwy1z+ ;t h of an object (mass = 50 g) on the endtz-qh 1wint *dy+;hz- of an 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m withr*6avpj2 t o+4yg vak. a constant kinetic energy of 128J. What is the magnitude of the vjk ov2+rt6y gp*4.aanet force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled inm9u :, w)ciuzo3/vywe a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on tuu/i)wv :oz9cmy3 w,ehe ball during each revolution is:

  99.22: A child whirls a ball at the end oi .q+ .kfhyk-(b a8gho sy+ul4f a rope, in a uniform circular motion. Which ofh 8qluhkyafo-.ik(.b4+gy s + the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mx3 d hbqgnkcw/8u3-a 5ass m to a string 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 qawhd8x3kbc5 /3u-gn maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of length L to which it is ati1imsq6 iq yxsxg0)4- tached 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 when the mass swings thr40-gs) qiyixms61xq iough the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figd9fb+, flo-ul ure to the right. Assume the car has speed v and the tops anl- 9+uflf o,bdd bottoms of the hills have radius of curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.cup *xjakf:m shqx*j8a 15: c jwxi;3+0 m/s. At the very top of thj p3hw5 ;x+a**fi1: mjs:j cqau8kxxce hill, the shape of the road can be approximated as a circle with radius 25 m, as indicated in the figure. Which 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 moving in a vertical c08kdw dzg- e;o 76zkatircle at constant speed. The magnitude of the net force on the sphek 6wkzdzt7do0-a8 g e;re

  11.47: A simple pendulum of length Lhasa point mass M released from rest *)l1 w1wm yufr(d,kl:opt sig8*iuv* 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 ,kvtflu:)g8yii1wsouwld r * (p 1 m**force 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 sd.fqw1 b cjixrbfk(9j(fr173 imple pendulum. The mass is released from rest and undergoes simple harmonic moti brf9xqjk(r7fdcb (3 .f1 1jiwon. 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) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopperv9sb;w (byl wm3u8s4. (dod nb moving at a constant (lnodub .syv;8(4 wbmw3 bsd 9speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to(78aouwijyl,gag.ji( r9-fd an ideal horizontal spring that is upstretched. A person extends thuj .8iygl9 o,w(- 7f(ia radgje 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 connected 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 constw- k *zbkoxs: 1h,km9ye4k*lgant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the ms xgmz4-w* eo,1 k hb*9ly:kkkass when it is at the lowest point of the circle?

  14.23:Two small identica4voty 6n78hy 6+zkic yl coins (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 through its center. The distance of the coins from the center of disyn 4ky6o6y t+ hc8i7vzk 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 *w (-wo igmbe)moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length of 2.50i)o m*(-bg eww 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 ii6epop3,z 0.j4xlidgn uniform circular motion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 mp4 dx3pj.lz6g0,i eo i 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 horizontal di90 t gpsmjl2.xsk’s center.j.gmt92p 0l xs The disk starts to rotate from rest about its center with a constant 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 distancn3i5/zbv8 fkhe R =1.75 m from the fixed center of a disk as shown in the figure. The divbk/8f zhn i35sk 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, starting at the topw.nqmzu upm :*f58)zz , with initial speed 17.0 m/s. The object’s speed increases uniformly until it hu5:8 zz*qmf.n umw) zpas 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 speed 17.j-zo ifqr1:9jjd 62, hng 9tff0 m/s. The object’s speed rfz ,f1 9qf t29n johj6j-igd:increases 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 time for this motion?

  17.38: A small 2.0 kg block rests at the bottom of a bucket:d brr(2sa s*9j ttnzc +2ob7g. 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 j no(bg9 tst7 :rdzcrsa2 b+2*moves just fast enough for the block to remain in place in the bucket. 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.