95.02: An object shown in the accompanying figure moves in unifw)7v b (drm *p izoq;g*me+,kiorm circular motion. Which arrow best depicts the ne) 7*iv+,dipwekg;o q*mr( zmbt force acting on the object at the instant shown?

  05.31: A child is beltewukdnfhz:r;2x3pgg l9f0 1d ;d into a Ferris Wheel seat that rotates 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 3rfdp;21f:gzu;gk 9xdn0 wl hand belt?

  08.14: A particle continuously moves in a circular path at constant speed in aj q-dk/+cisr)4 yu(ou0 i,nhm 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 ack0+s)i/ro4(u-qmh jduy i n,round 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 circuk6t, w,zl)3.iv) 0 -zabbcpolnjej p3lar path at constant speed in a counter- clockwise oel)p,36bjn,w)-pzjzi 3 cbk. la0vt 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.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwlaa)wb/. zxgp6a o0 b(g*tx w1ise with constant speed around the vertical circle shown. Which arrow bestgzabp.wxa(l0/6og*w ) a 1txb indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small md6u(3k)gb t;v 4ig iawass connected to the end of a string counterclockwise in a horizontal circ6bwg 43v(;ki iatdug )le 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 path should she let go of the string?

  15.23: A car moves with constant speed around a horseshoe-shaped path as shown t8ntna26u7d:7c dhd g with the arrows in the figure. Which one of the following choices best describes the direction of td n ngdt8267th:duca7he average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Mv,e,aq,e3r r joon perform an experiment with a simple pendulum that is released from the horizontal position at rest. Atq,,erj,v ra 3e 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 v3zw ubdj3 2lif;e4 p2object rests 2.0m from the center of a rough turntable ale3fw 42dbz2;p3j v uis 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 of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kg puck moving in a circle ofx vw.z fd5 7l7(cad. ceyx(n5l radius 0.5 m on a horizontal frictionless surface wicf(5n e azlw.d(5dl.7 c7xy vxth a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 0khejz m*2jh 01 ikil150 g) on the end1zl i mh0 ej0h*j1i2kk of an 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moveuw5,fc9f5se81v0e u z5 js0gw gjtiv: s along a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the m,1cfzui 9t55 0we 0fv5sj:ejvugg8 wsagnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached toyfeo:-(rr q, c a 0.80 m string and whirled in a horizontal circle at a constant spe:qorfy- , e(cred 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 rope, in ax2 mb w;q6u3+2btvd/wty- ty x uniform circular motion. Whictm- u+w22y vt ybxb3;tq6dx/ wh of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m t87 c d((mdvxgeo a string and whirls it around in un7c mgxdve( 8d(iform 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 tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of ley(8yz,4x qg qzngth 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 string wheqx8yzy4 z,(g qn the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in iyl-cq( ,jfbug(ktln7 5(3gn hilly terrain, 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 dr (b-gnqcu(ki7yf 3tl5gl(n j ,iver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a consia6 enajdg5c9nv ,.8 gtant 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 of the upward force exerted bycg,ne n8g5vaaji9.d 6 the road on the car?

  97.13: A small sphere is moving in a vertical circle at constant sd5bh) ujmwty8db; 4:i peed. The magnitude of th htbi judbm:8y;d )w45e net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released f(.4m6(gy.oy c (f dh a5ptcjigrom 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 5jp(. dgc6m(iog4yy ca h tf.(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 simple* pre a my)mps;)zah*2 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 mayep );r2)*zha m*sp through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopper moving v)q ab eq9i2co*l.d3rr.71rfguc b9a at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what happens to th.q1a9q2bd.3 afrb o7e *v )u9ccrrilge speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is a s:hlag4l )bt-t rest on a frictionless surface, connected to an ideal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this locatgl4)-hsl at b:ion 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 ma-ek7w8 orn q2gcmp;8yfc(y n-ss with a constant speed of 3.24 m/s in a vertically7gkncf2;- yeo-pm8ywnc qr 8(-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 identixk 1;a wch4gxk3s/w8p3 ym6imcal coins (labeled X andY) are at reston a horizontal disk rotating at 6mhywg /3k ap4skxw3xm;c1 8ia constant rate about 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 mou/gb :nulkt13 ves about the string’s fixed end in a conical motion with a constant spek/ugunl 1 3b:ted 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 hbttva-y-o -+xc12ufbd7gw1 in the figure. The string to which the mass is attached has a lengthgx7-dbt-c b vf 1w12yot ua-+h 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 from a horizontb1mmcitw-gm 6 6g8*rx e+)twial disk’s center. The disk starts to rotate from rest about its center with a cong met6bm8t+61xmw*)cirw- ig stant 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 v* 5 aq1j;svy ,dfx -b) w6d/v9ekgnql=1.75 m from the fixed center of a disk as shown in the figure. The disk startsa/sby)-*v6g9d ;n5qkjvv 1d fl ,exqw 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, wiqmy0/h+ dnwl .via)q :th initial speed 17.0 m/s. The object’+nil/h aq wv.: m0yq)ds 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 in a circle, hq5w4-szex.q starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly unt.-5 s xqzweq4hil 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 time for this motion?

  17.38: A small 2.0 kg block rests y ) adyexzkj0iu07:(jat 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 point in its motion, it moves just fast enough for the block to remain in place in the bucket. When the bucket is at ax0y0ejuz(yiak):d7 jn 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.