95.02: An object shown in the accompanying figure mo w5jiilrm.s4 h du,8c;ves in uniform circular motion. Which arrow best depicts the net force acting on the object,hsd.w muj 45i;rl8ic at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates cou4 pax)8bvi4hbnterclockwise at constant speed at an amusement park. Axi8h bavb 4)p4t the location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuouslu:wor+ b4nlat8wql a hf(l;ht:f; ;8l y 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. b8h 4;;:r(f8 u+lnoattl :wqhlf a;lw 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 cons:g.d7ojl) xq idmj04s-w 7vzm f8jgs8 tant 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 circf -8sq)j4 iwl mg7xvom: 0.g7sjzjdd8le from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant js 9o.npxj22zspeed around the vertical circle shown. Which arrow best indicates the direction of the objectp9js 2zj.x o2n’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string counter n+p 1r; qka; fntyt;euo;k,:kclockwise 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,q k nu+ rt;knyfoak1p:;;; te which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speed around a te;hg i.16 umbhorseshoe-shaped path as shown with the arrows in the fitu;6g1i.m ehb gure. 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 exq9/csec 9gvvf6,ta6 n/ n :ezsa (uk;yperiment with a simple pendulum that is released from the horizontal position at rest. At the m 6ve9 gftqcu sn:avn,e/;a s9(ykcz/6oment 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 from3xy :wwsfxrhde-.l pir*.r 4, the center of a rough turntable as the turntable rotates. The period 3rpy w.w .x,rx-f :*s4erlidhof 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 necessf3gcgv*bfu s2/ +xir)nx u;y6. m7whb ary 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?cu mry hngx g+wf b.7 *6iufx;/)3svb2

  05.03: What is the centripetal acceleratiovzz x m75c*;zr s(t;:,untvhez z4wi 2n of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times a sec*2zz(t5 tz;w; c,i zz hres:xmn4uv7v ond?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m with(c3r ncjb pend7w1* g/ a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as itnbe (7cjc *g3 r/dpw1n moves?

  96.24: A 2.0-kg ball is attached zq ldyt/svmn4 h*69o+ax +4ayrvnt66to 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.zaarnly9o y*+m+6ht 6 v/nd64s4qtx v 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 circular m .z*s64w3uzqanu ou+w otion. Which of the following statemenu.* zu 4z+wq6n wosa3uts is NOT true?

  00.19: An astronaut in an orbiting space craft attaches y)x0 xxs8un,q 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 speq)x ,xsu nyx08ed were all to double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward unti.5egg* 1rj dsx9oofu 6l the string of length L to which it is attached 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 strisr*jofgudx 5e6 og.19ng when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road 8 mfk 7jp0fhmvs4 y8,zin hilly terrain, see figure to the right. Assume tf8f4j vsz hm0 km7y8p,he 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 moves over a hill at a constant speed of 12.0 m/s. At thexiv9- wj(iz;9pxcx -o very top of the hill, the shape of the road can be ai x(v9z9x-pcj;wox- i pproximated 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 speed. The mag xiv*3z.zaaj3nitude of jviz33a.* axz the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from rest mv6pan+aik0 )0+ 5 rogm(tfbcfrom 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 forcm ob) nrap+ c6a(gm0ift v50+kes when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string form.:e51t ba wh9v-jaq 5b.vzx z2ad2nqjs a simple 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 m q1 zz bda vhw .5bjj29a:2e5.t-vanqxass swings through its lowest point?

  04.41: A centripetal force of -dvrf +q;cep95.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is maded;qv- p re9c+f smaller, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a 7 +ufryhprih9xun 11dmfafx - f5-54mfrictionless 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 app4xh1f m u5fnhfpuixd+a7rm9 1r5yf --lying 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 mast-9x4tx b2 rmfs with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force actm rtf2 -txx4b9ing on the mass when it is at the lowest point of the circle?

  14.23:Two small identical vsdayu6e-6ptu- l7 l8coins (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the dise6v- 8u laul7dt6 syp-k 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 abouti( 5sg+1ryjtmh 2y w(d the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length of 5 +( r1symyijhg2dt(w 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. Th;; qnqo5 /oemie string to which the mass is attached has a ;qoo;meq/ n5i 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 mas(lbscg,09l uo s 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 angular o(c g0b 9l,sulacceleration 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 gh4 qcd u27u4.w*qv q3zly ks)kg is attached a distance R =1.75 m from the fixe*gs. 27 qkuzduh3 c4)yv4 qqwld 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 at the7vfykq h/9pi ,+2he rm top, with initial speed 17.0 m/s. The object’s 7y9e ip f,h2/m+q khrvspeed 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 in a circle, s 5 orhhwllnfyl- nut+ix 0;n;8f5:t4mtarting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle 0n5i8t;l -rnmt f nuyol45hh :xw;fl+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 o,nb( e d:-rwn: luneze6qihzc-4jg8(f a bucket. The bucket is spun in a vertical circle of radius L by a rope. When t4 6i8dgn(hz-ecne- zleqjnb wru,(::he 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.