95.02: An object shown in the accompanying figure movhhe,rknzfc*ch8o/;72r +fvz es in uniform circular motion. Which arrow best depicts the n fc7enr z c*h ;+v2/hr8,hkozfet force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwi d1sarqbd4r8q lvr9 :/se at constant speed at an amusement park. At the location a slrddq9 4rr8/1:vbqshown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a +, av/qmshh.z zr. q8av+x8qbcircular path at constant speed in a counter- clockwise direction. Consider a time interval during vsq m8v8xha/bzq.+zr.q h+ , awhich 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 continuously moves in a circular path a:;hjv9lx djh3t constant speed in a counter- clockwise direction. Consider a time interlhj dj;hvx:3 9val 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 clockwise with constant speed arolo/z 1 n6ip 1xz:5e1, sjnliqjund the vertical circle shown. Which arrow best indicates the directio6 / sji1q np,l1zzjlneoi15 :xn 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 counterjp;zf- pwco1rx;t f., clockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the twirling mass.tof;- jcpw; 1. ,zpxfr 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 shw3ksuj7hxyxy55zk h. l0/7fp own with khz57l3s7kwfxxh /yujy0p 5. the arrows in the figure. 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 t/ .l1c/0w akt j0-z td+exvwaqhe Moon perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the diagram with ezqackv /d/ww 0.taxj- 01+tl $0^{\circ} < \theta < 90^{\circ}$ , 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 frs:wbw 91us:gnom 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 friction is 0.80wbus:wn19:sg . 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 j:iwe u .ey a-f6mp1h1in a circle of radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 e-e hap1y.jf16 wim:um/s?

  05.03: What is the centripeta-c.l1a nwgru. sd7wy-l acceleration of an object (mass = 50 g) on the end of an 80-cm string rotatingg .cus7 . ywwa-rdln1- at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circu:zq:ld r6m ;st0dhdg yue()q1lar path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of theysdd1tzm ;0e:: 6 qh)(luqrdg net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled in a horiix:. (z0irisxer;ll/b:xet ov -ti 5;zontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done onbolievz t.-rt:x s5;xi0(:; iex rl/i the ball during each revolution is:

  99.22: A child whirls a ball at the end of5h,ur ooq1nt.f 3l-w z a rope, in a uniform circular motion. Which of t,q t wur-1. zhf5l3oonhe following statements is NOT true?

  00.19: An astronaut in an orbiting sj4nm7(qp)jzb7nyi g2;oe vx 2 pace 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 ;ovb2 n2i7jn 4pzgme7q) x jy(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 ;hg)zzqw.1(e c*p1 zkrt vi4 ooutward until the string of length L to which it is attached makes a 90- degree angle with the vertical. The masoeq.t 1)c;4gzr1pkw i zhv(z* s 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 rop t(/p9ljd:tfgh+. g2 g3 4vifigs 7uzad in 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 driver of the ca hl/pg(7ijt+p.f9f2vg4g :3uzs dgitr is most likely to feel weightless:

  17.10: A 2000 kg carw ps.l5gn2hs3 moves over a hill at a constant speed of 12.0 m/s. At the very top of the hill, theg3 2wp.5lsnsh 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 moving in sm nex889ta 0va vertical circle at constant speed. The magnitude of the net fen m980 xvsta8orce on the sphere

  11.47: A simple pendulum of length Lhasa5fonr-1 yd ;de lq67bh 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 5rnqf;o d ylb1e6 7hd-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 forces when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simple pendulumaop b(k.a0/ix . The mass is released from rest and undergoes b(/o 0kaa.xpi 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 forcec6/0ap ,a nalk 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 rn6a0l ,acp /akadius 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, connected wslm2axjj m1fpc ;98+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 douxm;p1 mjs9fa2l+j wc 8bled 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 cons kwwhf7,hy.zux1+ 7-ry/j itswz*ji;tant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force ac;h.zk 1x*j/ww- i 7t iz7fyjwh u+,ysrting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical c1jco0b q;n*poavh2j *oins (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of the coins fo;bpqc j*2hj* n 10aovrom 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 01 dxee;o/aa mwl(jgj;cqs97string and moves about the string’s fixed end in a conical motion w1eg jc 0(lad79o;ajx esqm w;/ith 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 indej(l07p+ 0alllq 4ox uniform circular motion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and formsldalx4 +q0 l0loje(7p 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 res*9t8 dhwuzbx 4f5rk wzq9 ((zct 30.0 cm from a horizontal disk’s center. The disk startsz89qwu w(94 rxzcbd(tfh 5z *k 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 attached a distance R =5:; g0otl rmfnua;7t+5w e ko/wd+ law1.75 m from the fixed center of a disk as shown in the figotg+dfl:ealmr/o7;k5u+5n w; tw 0 aw ure. 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 the top, with initi dw,x.9j8zhkatl i,d. al speed 17.0 m/s. The object’s speed increases uniformly kaj8,9 tdd.zxwlih. ,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, starting at the top, with initial spat,xx3ts 38 w;xrbq g7eed 17.0 m/s. The object’s speed increases uniformly until it hasqt stx7,xax3g;rb 83w 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.2c2gwfa-5gwq m9 pj6y The bucket is spun in a vertical circle of radius L by a rope. When the bucket rea5wjfg ya2 p2gw6cq-9mches 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.