95.02: An object shown in the accompanying figure moves in uniform circul y6. adifv-ec +7fj;0kpt. tz itdlq48ar motion. Which arrow best depicts the net force acting on the object at the i l6d itjaec.fid4p vfky .7t8-+qz ;0tnstant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates 9 ;vnk;y(qmsucounterclockwise at constant speed at an amusement park. At the location shown, which direction bestyqs9;mnkv u(; represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a cir3.q tjux;i mh*cular 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 the circle from Poinx.;hu*iq3t jmt P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously 2;s,o :hawvv dokp((amoves in a circular path at constant speed in a counter- clockwise direction. Considw s2(a,vkp; oh :(dvoaer 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 with2me+kij *j4wknj9,y o constant speed around the vertical circle shown. Which arrow best indicates2j i * 9monk4ykjew,j+ the 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 a string counterclockw1 dag7giu2 ix 6ad.wq+ise 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 poi gii .7agu6x1d+a wdq2nt 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 horseshoe-sh0i j4xm/,fyl lv9lc3paped path as shown with the arrows in the figure. Which one of the following choices best d ljl,x3mli0f pcv4y9/escribes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experio9lkgki 7.kh6cd u1wg8y5-i qment with a simple pendulum that is released from thwg7do6iuki k9k c.-h l 5gy81qe 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 the center of a rougheh)l mc*v0px932xhti turntable as the turntable rotates. The period of the turntable's rotation is 5.0 seconds. The coeff pt2hl9ch 0m3x*xive) icient of kinetic friction between 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 is necessary to k o n+7t,3o dix.oyf6yneep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horiz nf3.yn,7xy+o ood6 itontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripe y+gu:8hbfh. vtal acceleration of an object (mass = 50 g) on the end of an 80-cm stri +ubvhh8:.gfyng rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontabuj3 wao 1lhcf/ 1mw-*c z6g5yl circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude ofobwh-11f aj*5 y3cm 6/zwuclg the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string awr9g 1vw)jujc (8r*t1679sj tsfk mtxnd whirled in a horizontal circle at a constan v7st1(6r89r*ftk g1txj uwcjs9)w mjt speed of 6.0 m/s. See figure 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 uniform circgkho g ,,4eq alr5lx7,ular motion. k4egroh l7qx,g,,la5Which of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a masspah7f(huy0zf g.70 de fm-6pu 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 maintain unaf0yh m6peg.-u p uf77z(0d fhiform circular motion would be

  07.22: A mass m is pulled outward until the string of length L to which it p59f lj9ns9lqed:w,t is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings through a,sd 99ql5e9j:f npltw circular arc. What is the tension in the string 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 rightpq gpdfg.gbf-4t+r :;. Assume the car has speed v and .pgg;bdfrfpqt+ 4: -gthe tops and 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 hie,xhg91( cn epll at a constant speed of 12.0 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 eh1pex,nc(g9the 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 ciq2mmo fx+)m+.+xw7v0 j ceptb rcle at constant speed. The magnitude of the net force on the sphereqowx) jv .+m2txcfep 7 bmm++0

  11.47: A simple pendulum of length Lhasa point (w e k3p 0ed68emyss1y5;hrjrmass M released from rest 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 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 (pointh dm6jrr0e3 syes ewp k1;85(y P)?

  16.32: A mass connected to a string forms a simple penbpsp :-db1 3 aado0wf3dulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the ms d aa3bpf01o p-bd3:wagnitude 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 newt2 p.uhjew2rz;6+syms dy vq90ons is applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius+ jdr62uz;0yq.hm9 pvy2 e sws is made smaller, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at 3 bpg)ts(o1-7lb 7 d 0qyu koxu/pcud/rest on a frictionless surface, connected to an ideal 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 o/)td7g/7 y-o kl bus(01b3pd uq pcxuto 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 constant st9ic rnrv9 cezss(me/)8wwrl iy8:oy+3 ./mrpeed of 3.24 m/s in a vertically-o/ycw 8 r+rc. sivs)lwrmom / :n(ie9z39rty8 eriented circle of radius 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 coins (labeled X andY) are at remnejhsg 28 :z4z:r 4easton a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the diskgm rn:ja2 s:ez 4hz84e and through 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 strfnx:)yk:cids ru - 0y1ing’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length of 2.50 m and forms an syk yxi-r:)1fd:0u n cangle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circulaf)hb;dd hyar(d*e57o r motion as shown in the figure. The string to which the mass is ad7 oe)y5;*hd hf(a drbttached has a length 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 objecv jq.vk8a8wg 9t of mass 11.0g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant anguvk j88a 9.vqgwlar 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 objectro nkjv56zswyh4gq 7:/ p5ju 1 with mass M = 2.0 kg is attached a distance R =1.75 m from the fix7h1w5ukvon p5j j4/ rqz:y6gsed center of a disk as shown in the figure. The disk 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, startinm 2roq,: 4-p nxsjwu1jg at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwiojqw2m un j,xs-:p41 rse 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 :dgdi3r9gp6u in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it : uri9d6pgdg3 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 the4+;ua7vq 7 q qevhck,b 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 inq7+q ,h7;ckv va4 ubeq 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.