95.02: An object shown in ;.d1byg uj m8fusz5mc ;a1 wlv4v*7gm/xzx +v the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the o;bux v1 yvwa8c;z+f/v4lm*jg u 17x z5d g.smmbject at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat thatzk hu2fn//:g( fru*ez rotates counterclockwise at constant speed at an amusement park. At thf/ zgen* uu( h2/rfzk:e location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle cozb6k29wrg7 c ;tw7)b xf*gu aintinuously moves in a circular 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 hauatk7w 79* ;6r )cw2fbzgxbiglf-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 ca-/9qm mqe ve+b 94xupircular path at constant speed in a counter- clockwise direction. Consi49+qa upqbe9 vx/m -meder 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 ckny)(e4k 0 jf ej:qo08sdye86 j ;ajarircle shown. Which arrowa: fe0kq(n4)jy ke;sjj0r 8oyje8da6 best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass consh-gil p 4j)o4nected to the end of 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 mass to pass through the point go4 -ls i)p4hjlabeled 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-shaped path as sho 2 gqy7*nsv8e k9w3rfizuml3 dm- 7wy9wn with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the car in travq9fyulmwv7 ky3m-en89 gds2*7i3 rzweling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a slwh2s (vv ;/vv: /cwsn rsp56jimple pendulum that is released from the horizontal position at rest. At the moment shown i2jpr vv;v:/ sl/c6w vsnsw5h( n 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 rfm2e.9 p( jbkrough 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 static friction is 0.80. What is the magnitude of the force omfj p9 e.(k2brf friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kyrb qk3xh w+ 8/sue(w:g puck moving in a circle of radius :+k3qu8/eh brsw( wy x0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal accelera8yfc8 , fzn)6gd3i wfftion of an object (mass = 50 g) on the end of an 80-cm string8fff6f3wy8c,nid) z g rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along 6 gg;3 7a* jz q60tuz1bnfq7hnx5v1dvihwm 7pa horizontal circular path of radius 0.8m with a constant kinet dh1n6qi1a qv7jggx70hbzt 6 m3*uwvpf ;7z n5ic energy of 128J. 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 m string and whirled in a ho a(mwlgij;t4+ rizontal circle at a constilmw;(4 aj g+tant 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 ropefo8.+hpy29e9 m. v -shmeehnn, in a uniform circular motion. Which of the fo8mvhs py he9me +.-ef.hon2 n9llowing statements is NOT true?

  00.19: An astronaut in an orbiting yhe.b v a.2sm5space craft attaches a mass m to a string and whirls it around in uniform circular motion. The radius of the circle is r, the speed of . 5svb. a2ymehthe 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 circular motion would be

  07.22: A mass m is pulled outward until the string of lxyqcwou ,+ vs;qm)72 y8 wb:nwength L to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings through a circu;bc wy+u2sq q8m,y )ww xv:no7lar 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, se)jse jctqvp-z:n3, d9e figure to the right. Assv:q)j t,n c3d spze-9jume the car has speed v and the 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 movo(q(bz 2hi,;)ogctj ai5w +cmes over a hill at a constant speed of 12.0 m/s. At the very top of thio5icc(z,+ qmt bo(jwhga ) ;2e 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 vertica6jz35h)nlaihu aej6n/9y,o sl circle at constant speed. The magnitude of the net force on the sph6hhjlu/an5 aeoy )96, sin j3zere

  11.47: A simple pendulum f2 ar-ig3js5s3e,(uxl qey- u of length Lhasa point mass 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 t(x35elu y 3u-i,aqssgj rf-e2he 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 sdrj0tr2twj +/ck*z 68dj. ba wimple pendulum. The mass is released 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 thet kra.bwjjjw2/+d*ctz8 6dr0 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 applgy-4fn9jtgzi; .ulfu ;eg ry p j;8h5/ied to a rubber stopper 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 frequency f, of the stopper? j8 pgyy eu4;/;g 9ngltrh5fjuf;iz. -

  05.28: A mass, M, is at rest on a frictggtdto(5ismm qn p,.+csj jm/ 9fx /1.ionless 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 to equilibrium and the mass connected to it is now doubled to 2M. If the s,m.+di.m ps xf1c jjs//gm (ngtt9qo5pring 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 mp5aa:(qbl 61 nxo:cbth:u ghb4 8or9zass with a constant speed of 3.24 m/s in a vertically-oriented cir rob :p 4qt:hob b9znhua5 cg1(:6ax8lcle 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 (laf; bev3:pjy6tbeled 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 distanej3; p6bfvt:y ce 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 otbi :ch( 6 t.f,f62sng3ztdjand moves about the string’s fixed end in a conical motion with a con 6tihftgbjsc 63d,.no2(f: tzstant 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. 6uv.i*g qt1b a.mf y6ov(pt72l de)yzThe string to which the mass is attached has a length of L = 3.00 m and forms an7vq(6f2i *)tgl 1oz6yy.uapmbvdet . 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 d1k d7xkhxb9s72cq oh ea19.kioe;y f 8isk’s center. The disk starts to rotate from rest about its center with a constant angular accy;c7dxk1eoi1.bo x9shq ah78f2 9ekk eleration 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 wit(1t7iibk v 4uh:l/ flv6hv.ghh mass M = 2.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the figuiu(/v1fhk7g hhl .6:v vlb4tire. 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, zprv )dvz.m3 s(*k( nvstarting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockmpn .s*kd v3)zvz((v rwise 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 .964mah qmp kuinitial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counte4ump kqm6.9ah rclockwise 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. The bucket s s)r04otw. d lhwlw;3is spun in a vertical circle of t.lls 3d0hw) o;rw ws4radius 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 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.