95.02: An object shown in the accompanying figure moves in 1c7 n1 -rhptyfuniform circular motion. Which arrow best depicts the net force acting on the object at t1-tyfphrcn1 7he instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwis : z83gioumiiphq (i:5e at constant speed at an amusement park. (qmi:o hzp5ii83ui:g 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 prqnb1egqc8j 569n 9nn-3rnpx ath 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 Ponn3nbr9qp5e8-1qn9c x gr6jn int 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 i. joi 61p 20.wtwv0oasue h;gbn a counter- clockwise direction. Consider a time interval during which the particle moves along this cir juibv0w06sot2;g pe o a1.h.wcular 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 constant spe omva)u6p/ d7bq (ns0ced around the vertical circle showaoc6pvsb)0q ( dmu7 /nn. Which arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small masmmw8q7kh5i n. s connected to the end of a string counterclockwise in a horizontal circle above her head. The figure shows an outline of 5.nik7qw h8m mthe 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 ar0omt3.se ,hp uound a horseshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describs.toe mp0 u3h,es the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on thj/8823swi yr(: m7c4 bxzza1rv:yaw hsft rq; e Moon perform an experiment with a simple pendulum that is released from the horiz7aiy rcv hs bat8zww;jx(1r s8qf yz:/43r:2montal 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 center of a ew *jnnh y78,a7ewb/lrough 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 friction is 0.80. Whatee8w*nyhw,n bja/7 7 l is the magnitude of the force of friction acting on the object?

  07.19: What net force iem r68p7t . .u m1mbjo0idppe,s necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizont7 ,bopd8m te.6.irp0jump 1em al frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of q-sys1/bhn s/ an object (mass = 50 g) on the end of an 80-cm string rotating at a consta1/nysqs -h s/bnt rate of 4 times a second?

  09.24: A point mass moves along a hor d.x.1h)e;xg fxdmtz. izontal circular path of radius 0.8m with a constant kinetic entxf gd .xxdh.m);. z1eergy 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 attached to a 0.80 m string 1abw. t)to) x *tlrd*vand whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the ball du x*d)1 wtlb*).avttroring each revolution is:

  99.22: A child whirls a ball at the end of a ropumnb p ;gr *dn-v0ej:.e, in a uniform circular motion. Which of the followndv;r 0e * nbjmpu-g:.ing statements is NOT true?

  00.19: An astronaut in an orbiting space ib8 19 rj5yl*cwel7xx 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 tension required to maintain uic je xwy*x851r9llb7niform circular motion would be

  07.22: A mass m is pulled2w n5hk.rc 0v ayz0j7m9 nq;uy outward until the string of length L to which it is attachewj0mkn0 .y2 n v9u5haq7 zy;crd 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 when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly tew*/+gkrmhz rdh x i:+w oqh45e6t)s1 qrrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius ofr/zkhg6rx +1oqe5 t+dw: h)his*q 4wm curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car move d(tc 32oqzt ht6c72chtp8g c*s over a hill at 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 of the upward force exerted by the road7( 3hptcc2httq2 8cz do6gc*t on the car?

  97.13: A small sphere is moving in a vertical circle at constant speetzx / tizzlk/6wc v0o8a9jz2,d. The magnitude of the netovkz96il,x/ /ctw2 z j z08taz force on the sphere

  11.47: A simple pendulum of length Lhasa point mass Mo 1/r af/ect-d 5sc9yx 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 gravitational force acting on the mass by the earth, and F represent the magnitude of the net force acting on the mas1e5r9dx/ctoy fsa /-cs. 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 manrcayu8 ./pbp 4e6hn* weg g83ss 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 gr ngw* 3ycpep a.rheu6/n884bgavitational 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 of 5.0 newtons is applied to a tu3 0.z hoihwn6uw,i/ rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what happens to the speed v, andt i ,wu hho/3wn6u0.zi the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionleoocoln7dvzbh2qlom +p6 - ga+ ;0v p71ss 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 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 extonb mlol-p+oh pgv1 ;07c7z+v62doqaended 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 im)h0d gopgp39eu, t8+f)gjo a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the8g9 oitjmg)h0u p)f,oe +gd3p 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 horizontal d0m1uih n5. serwz.6 ysisk rotatihs.6yr1sz euwni5m.0 ng at a 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 isg.7 ieej 4j1zl connected to the end of string and moves about the string’s fixed end in a conical m zj47jeieg .l1otion with a 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 is in uniform circular motion as shownrlllr2y;ee/crj4:9 5qy ky8o in the figure. The s lcq2;orl9rjyey:el8 k r/5y4 tring to 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 11.0g 2frf47 bo 2yq e0rd(pwdqe/ n2is 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 acceler obfqefd0 24e nr227(yq/d wpration 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 =1.75 m fr c+871ns 6pnuu qy9y jcf9wfk5om the fixed cente+wqcys cu69 7n nf 5pky89j1ufr 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 circpbh-y+ykidm x)a e.xek i7.*pi4/p6 vle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise thvkhxmypb ) pk ii*e+7e6-x4yi .d/ pa.rough 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 mov1 z1kli;p.3szo5h rtr es in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increal 5 prrz11tzk.is;3o hses 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 time for this motion?

  17.38: A small 2.0 kg block rests at the bottom of a bucket.,11.fn quqv z h)qkays;9dn,x The bucket is spun in a;vuqh1n ,.qx z9,1akydf q)sn 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 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.