95.02: An object shown in the accompanying figure moves in uniform cir pc9te *bdxu5u -;vkt6cular motion. Which arrow best depicts t6v;du*tec59-bt p xu khe net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat thax ebk)mvf nf;81c; x6ht rotates counterclockwise at constant speed at an amusemen6;v mb8 1nkf;cx xf)het 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 at constant spe(dzgti0m3p0h1mj +u95c zt hged in a counter- clockwise dir3iztt15p(hgg h00 zmc+jd9m u ection. 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 velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant speed in a1uoi+wa bwa9 ( 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+ a1uow9(abwi 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 26f (xgpz*sz fthe vertical circle shown. Which arrow best indifz gszpfx*2(6cates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass cx9- rh6 faxg 3:bb jmf0triv6yam18g4onnected 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 bfrtm fxg 9 vh413ix- gjm6: b0ay6r8aabove the twirling mass. If the girl needs the mass 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 horseshoe 3.ny*i 8(kz6yxj nnwk-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the car in traveling from Wtoz y kx3n6*nnjyi (.8kw X?

  08.35: Astronauts on the Moon perf/ +loxbd86vdt0cz m ,lorm an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the didtzc,mox 80ll b d+/v6agram 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) po twicq3 )j2ze0int-like object 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 coeffici2wjqc 30zt) eient 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 forc+(u/ -oel-gg/dtnn9qw0 qu8 :j xhqw oe is necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontalj+qgq ugudl -(h:e/9 q/own8now 0tx- frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleratih+ *u +bc7nlr3rvrd-con of an object (mass = 50 g) on the end of an 80-cm string rotating rubchd l n-r*3+rcv+7at a constant rate of 4 times a second?

  09.24: A point mass mov2fe albrm/ :/ll 5ote4es along a horizontal circular path of radius 0.8m with a const2frl le:/mb 4e5/l toaant kinetic 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 attap5z/njrady v8,61a xt ched to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work do8vr1,p ja6x/tz5yadn ne on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular motion.,eokl9cpr5 qpu( 6rk3 Which of to(56 rpl 3ueq 9rc,kpkhe following statements is NOT true?

  00.19: An astronaut in an orbiting spacof5ry8a,b nsl;nmrrgkx+ nz7 *+9 * qre 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 the mass is v, and the tension in the string is F. If the mass, radius, and speed were all to double the t yxrzf;8 l,bo 7*5*mna +qgrn9rsn+rkension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of length L to which it is ata0i4cgc+ ,z zvtached makes a 90- degree angle with the vertical. The mass is released from rest and swings thr+0cg,izz4ca vough a 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,wky r9(8f)j4n;kyrd2a / cdnx see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The drd)/wyd2fra;xcn ry (8k4 jn k9iver of the car is most likely to feel weightless:

  17.10: A 2000 kg car /glel-jj8qgg *q5l8god 6s3n moves over a hill at a constant speed of 12.0 m/s. At the very top of the hill, the shape of the rol-eg8snqd l /3 o5gjjlqg6 8g*ad 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 circle at constant thhwbm8 -4jvx7mn c2/ speed. The magnitude of the net forch4mwxh7mt2/- ncb jv8 e on the sphere

  11.47: A simple pendulum of length Lhasx.wqtb:led w n un)13/a 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 graviwd tlbuw3x.1)n: n/ qetational 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 mt9(1,wp 2nnm/qiadkp3/jys xv/ . qnsass 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 the net force acting on the mass (F) when the mass swings through t kn9s/qpda/1q2w 3. vyp/ nins(,mjxits lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber s9u(k cu mh1 uo56p9)ynssk:yjtopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius 1unpcy y)(hms5k jk o69uu:s9is 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 ml(ej rtd8:ak u6vxfr4-7j8 jan 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 spring is extended back 30 cm from equilibrium, what is the necessary force applied by the pr m e6fk8j78jjxdtu rav-(l4:erson to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant speed of 3.24 m/s iesrb17v )8xe x4bq5-,dz wkoan a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is at the lo 5x-a)be81beo kd7x rw,v4sz qwest point of the circle?

  14.23:Two small identical coinqy8 *fg8fg6*nxfgz9p, o ci3ps (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendi8fyn** p8fg9c,o zig6 3pfxgq cular to the plane of the disk 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 conn m9vai;bi 2f0o0w9nl ,-nui hmt)zui6ected to the end of string and moves about the string’s fixed end in a conical motion with a constant sin,- 0i0 i)ibnz6 mofm;a9 wvh2 ulu9tpeed 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 l5,5q0i7 dzt/ddt9n kb(d/pfnt e1jbthe figure. The string to which the mass is attached has a length of L = 3.00 m and forms an dl75 9q ttz/( ,dfjide0n 5pb1 bkdt/nangle 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 c/4zz: ssb,9kpk m -btjm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angular acceleratzkztsj: bk-,/s mb 9p4ion 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 mewi95 utpz.m6ass M = 2.0 kg is attached a distance R =1.75 m from the f.z tu96m5ewpi ixed 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, starting aebe1(tvp7j n; zkmev98;q:qv t the top, with initial speed 17.0 m/s. The object’s speed ine1pb m;eqqvv8z;9j e(tn k:7v creases 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, . 1 puglh4kncs68y -dvstarting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an an.6l 4nyks 18c-gv pdhugle 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 tee eu)u) m y:oppq5mak-uz,mot6 4b*(he 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 moti -tuu ( ),pyoq ee6mm5zk*pab4)umeo:on, 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.