95.02: An object shown ud1 ne;qlhq pp4)3wz)in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net for );3 udh nqp41q)pzelwce acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwisx/dt 8 h2eg.qm4tbr .rmqev7l /7qog(e at constant speed at an amusement park. At the location .7rb8./gqxmh( m v 7otdger42/teq ql 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 c;j72;uqmrqmmk25ws3g w1smb b ot2 c9ircular path at constant speed in a counter- clockwise direction. Consider a time interv w9 mmt53c2gu2r1ws 7qmkmq;2sbjob; al 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 cumpoyor y;9v7 aj d));ontinuously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval durvor a;d7y9j omu);)yping 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 coe;x;6hhvs*, b ax ls+tc3 fl1hnstant speed around the vertical circle shown. Which arrow best indicates the direction of the object’s instantaneous ;hf hb1vlt63,al ec xh;s+s x*
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end p 0ukdx p)t0bjot2p9.e: e,hm 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 poiu hmkjb:9p .e,pttdo px2e00)nt 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 arowbblsgtd g37(f;i v be3*gj),und a horseshoe-shaped path as shown with the arrows in the figure. Which one of ;ief3bt)g(dsb bj3lg wv ,g*7the 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 pendu43sr* isuhfqu/ o 2gw8lum that isqig3u*ourf 2 h48 ss/w released from the 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 )d5h1nfyf,anrkir p1r(e3;k from the center of a rough 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 ;3dky )i51n1f prnr(ae, h rkffriction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force 6 3gqnfhax7t-is necessary to keep a 1. 0 kg puck moving in a circle of radiu h6g3xt-naf7 qs 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal accelerakb*, f 8of4 y4uav,o nfryn,s(tion of an object (mass = 50 g) on the end of an 80-cm string rotating at a con* oys aov( fb,nr4,4 8,fnfyukstant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.qwdlnt6f,n+7y08i a c 8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on n6nt d0iyc7f8+ q,w lathe mass as it moves?

  96.24: A 2.0-kg ball is atbw,gqf s9lu+18zd0u04v2wyrd0oo ;dr vqo) etached to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to th1o;s0vzdyu809qwb 4ew2 fdvq0odr + ) lgu,roe 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 circular moti yi: j5d/kqy1gon. Which of the f q/j 1yd5kyg:iollowing statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches aq2jg2dm 9u8a, 03ldjweecv,rcozc 6 / mass m to a string and whirls it around in uniform circular motion. Th 3 j vw28mr a0ulzcq6e/do,ecg,9j2c de 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 uniform circular motion would be

  07.22: A mass m is pulled outward until th,b )t.+w7 o2cz8uvzz l9 sukgse string of length L to which it is attached makes a 90- degree angle with the vertical. The ma72k w z),8 lubu.t vsc9gzo+zsss is released from rest and swings through 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 t58w wzjgd0*2:g opk gxerrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills havegd8:g p*5wkz0j wog2x radius of curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a1 yj-4(fx9,w w cl0anqeig59c 4vmsm e hill at a constant speed of 12.0 m/s. At the very top of c ly i feqa(x449s1wmme905,jvngw- cthe 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 movx yov pu .i57pg bjlt/z)b04m4ing in a vertical circle at constant speed. The magnitude of the net for4o0 gm tp)jy5/zpux bl 4v.i7bce on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from rest from x,js52q9jo k v5yn)wk 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 5jn2vxws,oj k)kq y59 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 878z qpxzrcm- a string forms a simple pendulum. The mass is released from rest and undergoes c8z-pr7xqzm 8 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 its lowest point?

  04.41: A centripetal force ygpy, m gkd30/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, but the radiu3/kmyy ggp0d ,s 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, conzqey0j3kk a *;nected 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 spring is extended back 30 cm from equilibrium, what is the necessary force applied byka z3k0 ;qejy* the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a co yg mmu/j0roxj5: :ilxto jr2u4(p70gnstant speed of 3.24 m/s in a verticallyl 70u:umyoixg:jm 20(gxo4j p/jr5 rt-oriented 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 anl, yr (lkgm03axu8l(qdY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its ce l8q xlakrmg(l0yu3( ,nter. 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 is8pglkri hv.oe4 lu8bxp:r 65pg wt6;j6g 6t/t connected to the end of string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s.he. g8rg4;v6jlbp5t8ru 66 ti w:gpt xplok/6 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 unifo 02ql4 t kbfaaeh)lwe-6y tu,)rm circular motion as shown in the figure. The string to which the mass is attached has a u bwle)ef yq-2thl4tk0 ,) aa6length 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 11.0g is at rest 30.0 cm fr+t m go2j,h vix63rb.xom a horizontal disk’s center. The dixt6.bi,ov j23mrgh+ xsk starts to rotate 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 dvz2)fyuk kpwx8o6+m0g (qz6 attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disgwq6m )dy+fxzukv (k6oz 8p 02k 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 the top, with ino9-kk la+5 e0;lgy- a.qwn7;ln8o.pg vpsmu kitial speed 17.0 m/s. The object’s speed increases uniformly untal-l. n+og9pm.ngys8auwok;ep;50v kql 7-kil 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 circld* q 4mqbhg)0oe, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it ha o*b0)mq g4dhqs 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 bl4dj4(2fah gn vock rests at the bottom of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest pofjn 4ha4 g2dv(int 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.