95.02: An object shown in the accompanying figure )tiin-n:emp axhj;:)44z qromoves in uniform circular motion. Which arrow best depicts the n e)4i)nj- m:: xt 4nzpqr;iaohet force acting on the object at the instant shown?

  05.31: A child is belted into q/up69y zjij:a Ferris Wheel seat that rotates counterclockwise at constant s6j zq/p yu:ji9peed at an amusement park. 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 pyeyiom2h .xsk2 -:m:gath 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 sx:ik y2.me -m2:yghoaround the circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuouslybxe+x7p3-l:bk, z iq: b,mibx moves in a circular path 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 ci :xmk -z b7x,biexb+bip :lq,3rcle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves w1ziz:3v47c qptq2,a litc : wclockwise with constant speed around the vertical circle shown. Whiczw13aqcq: :ip4 t27,wlzivt ch arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a sh,y.icis-7mx)f +azpmall mass connected to the end 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 iy-pixhc7afzm. ), s +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+6d-j1tm dduh b9ioc 5 constant speed around a horseshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of cm1i-bo d56ujdthd + 9the car in traveling from Wto X?

  08.35: Astronauts on the Mcw h*s*9uuei z :gv95f83f )kcob cpy-vs.w/moon perform an experiment with a simple pendulum that is released from the horizontal position at rest.h 9/-us8 5fc:iy.vmwfp)ccwosz3 gbu 9e* k*v 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 a2mr zd:dl7q;dey2f1 rests 2.0m from the center of a rough turntable as the turntable rotates. The periodam:ddz1qe; y l7r2df2 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 necexj96x c2o vi7wssary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surfaceio7x2 cv6 wxj9 with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an objew w*l3h3 yr,kbct (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of3wr3bl,w*h ky 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0 5-a tx,vjo(4ofr lo0u 2up-ra.8m with a constant kinetic energy of 128J. What ip5ualufr (-x jr aoo ,2t4-v0os the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is a tn5 ey y 7*vzwxjm6at9b7q9;ettached to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work wjqte6nzb7ye7 m9a yv5; 9*xtdone on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rt9t;soyd yc: 718t1d ngbl es5ope, in a uniform circular motion. ng5tc7 dtt:l dy1; 9sy81b eosWhich of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craf ogbqqye :m 82x(sk-ezs0-awm3, svu+t 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 stam+qu- e:3zoksqy-vgm0(s2e , 8sxbwring 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 stritum-vf23 ch)dp+7opbk pr 9x pirkp9 0n0v/7 xng of length L to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings tht7xxhpkrc )b9f - v9 p /0ri72poppv3dum +n0krough 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.p9q fe12lv np4clkhz;7)+vz qmu4 o y in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills hac 2fn l)4p7uopzzhm;yvk +vq .e9l1q4ve radius of curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a cn 4var-(gp8d;gazj nh .7n4mgonstant 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 road on th87dran 4pn4jzvg(- mah ng; g.e car?

  97.13: A small sphere is moving in a vertical circle at constant speed. 8 g mak ,f.z*f.cyjmt+The magnitude of the net force on the .,tj*mfak z8. myc+f gsphere

  11.47: A simple pendulum of length Lhasa poin(az*hcpq r5gat 7p) s.t mass M released from rest from the horizontal position shown. In the absence of air resistance andp. (sah5 p*c)7rt azgq 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 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 e q3ngk7 ,x7 g1t7geursimple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magng17e n,7eg3q xtkg7ruitude 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 forc/(j jmf+6t;ofna y( nme of 5.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is apm;njaf+( fjy/t(6omn plied, but 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 resi5rd) 9hen5 ust on a frictionless surface, connected to an ideal horizontal spring 5ir9eusdn5 h)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 by the person to hold the mass stationary there?

  12.22: A girl swings a /a tthqu*+h d hg92a0p4.0 kg mass with a constant speed of 3.24 m/s in a vertically-oriented circle of d /h atah902qtuhg* p+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 uek a5bm (8(bs8bufa8andY) are at reston a horizontal disk au 58m absbk8e((uf8b rotating 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 is cocuq4t: 6f(m ixnnected 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. Tu6 q f:t4x(mcihe 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 motior4hw o wi;7 zvgt-1)a22tbq* mrpu2xg n as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and forms an angqwiv1 mu7-*p tx) bhwrzgta2g ;2or 24le 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 resty 5xlr z:wiie 5g25qatr1)r5 it(c2tkc-+xm b 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a ctrqbc k5exm)g y:w1zx l 25 r+c(ri5i-atti25onstant 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 dis0 jocb;w9)*v 0oo)rxs2ve fvg tance R =1.75 m from the fixed center of a disk as shown in the figxoec 9)0r2)fobv0 *vjv;swogure. 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 initial speed 17..k:b3mx k7 bre0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle .krk x37bb:emof$55^{\circ}$. 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 17yia g p-*d ct2i(-fmk5.0 m/s. The object’s speed increases uniformly until it has moved counterga2y-tpifk*5c-md( i clockwise 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 2peoz zb9o1 +khkiilh0y 0 d 9qk:8lfxs0,+nhbucket. 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:0z fklxklq,1+8nbhhpo02 e0isy doi z+9h9k 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.