95.02: An object shown in the accompanying figure moves in uniform circular moti.nnrt: u r/on1b ;.o bbi/,jhyon. Which arrow best depicts the net force acting on the object at the instantth: b1; i bbryr/ n,./n.ojuon shown?

  05.31: A child is belted into a Ferris Wheel seat that rotat y:yq/2wwh,zfw j)qc l gk(7a-es counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents thek:g-wlhaw w( /j7y 2qf)c,zq y total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular plh4/xme 93bzusin)f l1k3 v 5uny8z/tath 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 ch y/x8l fi15nb) 3/nuum ks3ze9z v4tlircle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuouslyvic l(6r .qt3n moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this cirqi.n rt(l c63vcular 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 constanxd,9l32 u nuxm,bed;et speed around the vertical circle su, 2e lnmb,;9 ex3xdudhown. Which arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string countef9pa 1uyf31 pbg b pb sp*xs7;n8;8fe;a:cqlhrclockwise 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 e y8l; pa 7xbqgb81a snsp1chfp;3:b f*;uf9pmass 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-8g5tju p6ltjvf4(oh) shaped path as shown with the arrows in the figure. juhovjt)5g6 48(l f tp 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 penduct uc5 2swc:ue14y/n ;( f4tpu naej;vlum that is released from the horizontal position at rest. At the moment shown in the diagram with cn ut scu/ yec;(w4:e;t a15nupf2 4vj $0^{\circ} < \theta < 90^{\circ}$ , 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 rough2t j o0j3ief938 q 7zzhtgpmchar. o8/ turntable as the turntable rotates. co2qz/3 r h88ht3.p oizm7afjjet 9g0The 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 kecxs l:k(n.4h dep a 1. 0 kg puck moving in a circle of:l.4ck(n hd xs radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 5j8n *i la(m( sk6z,lpzj qlu8:ceug400 g) on the end of an 80-cm string rotating at a constantze4 8ql 80( zpg( :, lajljkumin6*csu rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radiu2ryw 765s-i f o7tdkxgs 0.8m with a constant kinetic energy of 128J. What is the magnitude 7kwr6ogfy-s2 7 xit5dof the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to fspjr)xz,u w .uo8 g5mm4j 7l,a 0.80 m string and whirled in a horizontal circwzjgm sp 8mu,, 4j7flox).ur5le at a constant speed 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 a uniform ciljd n7z* 0zh3lrcular motion. Which of the following statements nl*7lj z0dz3his NOT true?

  00.19: An astronaut in an orbitinb*3.c3s-o( khu0gerh evw :qtg space 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 maintag*qew hrc:3kv-tb0 h se3.ou( in uniform circular motion would be

  07.22: A mass m is pulled outward unti,fk f:tuc b(z8l the string of length L to which it is attached makes a 90- degrebt:u ,fzc8 (fke 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 t*76ch56tsv hjq37n nuwbhn p. errain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. Tj7*hp vc bnshwt7566qnh 3un .he 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/t+e :gvr6 qfx6s. 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 magnitud6t ev:+x6qgfr e of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at constant tqm7n 4ifeq4 pp 6vd(5speed. The magnitude of the net force on the spherv5qe4f tqmp7idn6 p(4e

  11.47: A simple pendulum of bj.d ,92yh 6s t qwyq,rju mo 2f0ht:+5budn-alength Lhasa point mass M 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 repreq j5hs ab2dbn0. f qyh6 ,tmw9+j:tdruoyu-2, sent 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 pendulum. Tt a, 3 vvvxlbkfini; :fu 4e7p/jlq+;(he mass is released from rest and undergoes simple harmonic motion. Which one of the followivk x37(4 lu ; vifteil panbf:;+v/jq,ng 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 of 5.0 newton2gggkyythv *u4 ,xq t64, ti7is is applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, buu*tvqxy 2g6,g7ity4i ,gk4tht 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 ( .x0ak7kndav 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 location by applying a a7 (dkxn0k.v a10 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 consn0uwbe , r):ybtof7s j//zle r5,s7wxtant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is a,0/u7,:y)rewbbxf5wls/nes o r jzt 7t the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizo3kv kt75p..0vccszlcp. i6v zntal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of th lkz7vc pcv.vi0c3 5z.t6 .pkse 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 tomtut0fdxo(3b4w 3 3t q 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. The string has a length of 2.50 m and for um(bt0xqfto3 334w tdms an angle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniforgffvl,xosp0r 1 avzr+qa ,:97 m circular motion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and forms an x,po19gfv+,:arazlr vf 7 s0 qangle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mass 11.0g mi5s ypn81.zkis 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 a zny.s8m5i1k pcceleration 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 fma5; wv4x5 n(s15* kyciwtqnkrom the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constant angular (*mkiavx;n y1w cn4tq55sk 5wacceleration $α =5.00 rad/s^{2}$ 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 thsj,2 jk5e2 t:qo70fvmx8mno x30qi tie top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angl nx5omk22 vx0if 3qi :o0t mjs,8je7qte 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, starting at the top, with initial speed rumw9 31c6g65bzzw hu 17.0 m/s.65z6mwrg 913uwzuh bc The object’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 time for this motion?

  17.38: A small 2.0 kg block rests.f02w uavtn ty2:m2i y 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 point in its motion, it moves just fast enough for the block to remain in place in vui:y mt22 naw.t02yf 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.