95.02: An object shown68yaf-h+n xje in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on thefa jynx+6-8he object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotat.er))hua lh2-c hwf;c es counterclockwise at constant 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? -)r h2cl). fehhua w;c

  08.14: A particle continuously moves in a rc dj;1d.g p/,o3y0lwsnammlf.f 7n6 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 pmd/f msg no w1y.0la7jn36,p.; d rlcfoint 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 move4w ,v,t7u )eb2vpmefps 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 half-way around the circle from Point P. w b pve74ep,v tuf,2m)
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwh a.ojr9ov4ljsx,t/;ise with constant speed around the vertical circle shown. Which arrow best indicates the direction of rjav ./9,o;jlhx4t sothe object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string counterk)b, yy:0 zfxdgbtx7)clockwise 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 in the figure, at which lettered point on the pathb dzgk fx)b,x ty:0)7y should she let go of the string?

  15.23: A car moves with constant speed around a horseshoe-shaped path au j )s2 u4qwmlg+jpq :ax0o10zs shown with the arro4:ugjaq w xqsuj )+o0pm0 l21zws in the figure. 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 simple pendulumzzii n;upl3x b6h x0j*zvn4 *3 that is released from the horizontalpz0;6xubixlzjz v ni*4*nh33 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 qygi 3 :o1xd2icenter of a rough turntable as the turntable rotates. Theqy1 dx3goi 2i: 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 of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kg puck moving in a97ix4; 7ukoajlcx / o lz2i0ra circle of radku4l 7aicj;x r2x7/loo0 9ziaius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the cen8/w 4+mvd x(nl lu9ojhtripetal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a com8 h4w+dvlxjo(/9ln unstant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular pa)ag ,,aqnb,j fth of radius 0.8m with a constant kinetaf)a,,jbnq, gic 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 rxj)( sw,7j- zktwi 0+eq7rlyis attached to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figt07l+,e j j7i(ysq-xz)wrk rwure to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of aiz-; h 6ijv7hf rope, in a uniform circular motion. Wh6-hhfi7zji ;v ich of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft atta3o9uy;kzh x+oches 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 ma9k3oo yu+;zh xss, 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 length L to whi8mrtdx0lf s+-ch it is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings through a circular arc8 t+dlmr 0f-sx. 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 ri7pcjql9p6 z, zght. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The z 7pqz9clpj,6 driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill o95/jg*xvv +yt / zwgsat 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 the figure. Which one of the following choices best represents the magnitude / x+y*o/v9 gs5tg vzjwof the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at constant speed. Thb4rf-p wsfz6/g u)u+xmwia d. q f/)r,e magnitude of the net force on the u). +pfr xwwfgr /zf,i b)m -6/qasu4dsphere

  11.47: A simple pendulum of length Lhasa poin og7 yje/;cc/rt mass M released from rest from the horizontal position shown. In the absence of air resistance and friction, the mass swi/7gc r; /jecyongs 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 (point P)?

  16.32: A mass connected to a string forms a 0 6u pj5eya8g vuo5.qfsimple 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 the net force acting on the mass (F) when the mass swings througoqaju 5y8.up6 ge0v f5h its lowest point?

  04.41: A centripetal forcv2c 7mnv w*2k+ drbyz*e of 5.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, budmvy7 rnbw2*z k+c*v 2t 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, connecteype i.iyf2y yt46.ieh8e -(ukx8 8pvvd to an ideal horizontal skt4 uy-e6x28e f hyvpyv.8.8ey ii i(ppring 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 person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a cof4m.4nrg 7vhunstant speed of 3.24 m/s in a vertically-oriented7 n4ugr.h4fm v 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 reston a hori0,q *g1e jz(6dc/1bs vg/uc9dn tfe3o.i qgjm zontal disk rotating at a constant rate about0 o3ec eq* m1.b zjn/gs,9j1ud(qg dfiv/6cgt an axis perpendicular 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 connected to the end of string and moves about the tgrfqgi 1,zrk pm b3b.5v2;7h string’s fixed end in a conical motion with ambr qk5f r,iz32vp.h7;bt g 1g 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 is6y c l8g4kn2h (m0llla in uniform circular motion as shown in the figure. The string to6mk82hcl 4lnya g0ll( which the mass is attached 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 object of mass 11.0 cpoyl,h(e a;-g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to ro, c(aye;o phl-tate 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 distance R =1.75wx:r4tn :hi/ 9tks1uq m from the fixed center of a disk as shown in the figure. The disk starts thk :i/x: qu w41stnr9 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 cirk2 jfqs9 g/yv i qruq6/e;9s:ccle, starting at the top, with initial speed 17.0 m/s. The objectksgsuqyc9;9 e fj2iqq/vr:/ 6’s speed 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 final speed of the object?

  16.40: An object moves i+*5vbcpy ssn +n a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has mov pn*cv+b+s5 syed 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 botu;k 2mu+e4l2t shtb ;stom of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucket reaut;k2u 2t;+ mbshse4 lches 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.