95.02: An object shown in the accompanying figure moves in unive j .pkh*;r w1jupp:/form circular motion. Which arrow best depicts t h :1ve rp/upj*wkp.;jhe net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwi1ei ygxj(12kko(g hr8 se at constant speed at an amusement park. At yh1g exik 8(kj 21g(orthe 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 path aao rojwfto94gj+f*39 t constant speed in a counter- clockwise3 frjf+4o twog9joa 9* 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 velocity during this time interval?

  08.15: A particle contin wmc+ jjx,z4yw39ya(cuously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the wy9(j4j3ayx z ,mc+ wcparticle 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 around the vertical circl k-w6/zlc 7 j1bf6brmwe shown. Which zl b6w/w7b 6k -fjr1cmarrow 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*u1;/rx*nrzef hc z ;o 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 point labeled P in * /x;hn;forcuz *er1zthe 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(5mmv wnb3 t+0el3uc h-shaped path as shown with t me w3t( 03bn+l5hmvuche 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 the Mnz34xfkgfw 6 3f8cxu/ oon perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment showcgw6k8z/ f3uffx4 n3xn 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 objehct 8,** y3*stjuiv gkct rests 2.0m from 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 *y, ctvg* 3ts8 *hjiukstatic 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 kekikegq0:3 ( wwyp )1qkep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a s1:3wg0)ek (wkpqyk iq peed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an o,2hkojnd8u.a f dkt5;bject (mass = 50 g) on the end odntuakdjh;, 8o.2fk 5f an 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a hflqhrtpci1crm+ -0. +orizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude lr 1 -.+hficqtrmc0p+ 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 sp9kj eu qm7e8,tring and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work dem8u7p q,ek9j one on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular mobbnc o-xh 9.q*tion. Which of the following statements is*xoc.9hb-bq n NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mas3d6 5dbvgce5z s m to a string and whirls it around in uniform circular motion. The radius of the circlegdv5z ec56 bd3 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 untu 1)00r 1c pzztbzob ;)kf0xchil the string of length L to which it is attached makes a 90- degree angle with the hc1tbc;0bkzx ))p0r 0uo1fzzvertical. 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 terrain, see figic 6h cjaa19:exur/rw.lp-qz. xy* ,yure to the right. Assume the cc/zyr uj1qar ,p*.6 ax9.ly- ixw :cehar has speed v and the tops and bottoms of the hills have 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 af9 k4r8pyl+y1wnq pi3 constant speed of 12.0 m/s. At the ver 9k8l4i3ypwrn 1fq+py y 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 the car?

  97.13: A small sphere is movi6 4v,m/t)jk-qo ;tqx/ws4 mw oqw 0kecng in a vertical circle at constant speed. The magnitude of the net forcmqw4t)w ;sk v 6 t/-wo,oj4 0qxm/kqece on the sphere

  11.47: A simple pendulum of le*y+omg+xvj e5i l-b)kngth 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) x - v5giomk++be*jly 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 ie6v ;7dtmas0forms a simple 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 act0se t 7;mi6vdaing 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 rubber stjwvr )p1 -zs.kopper 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, and the frequency f, of the sto1w rz)j-.kspvpper?

  05.28: A mass, M, is at rest on a frictionless surface, connej v5dn383yhkvl e+z2slw bgv e7,9km (cted to an ideal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this locayv9 z8k,elvsv3m3d(l k j7eh5+2nbwgtion 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 mass with a constant speed ofqu:id sw,k4b)x wr k(2 3.24 m/s in a vertically-ori ,q krux()4sw :kw2dbiented 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 identical coins (labeled b,yo;)3v(tnrc.zel3 tt ij,lq ht-.r 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. Thee lylzchoib;3j .tt3(n )rvq,t-.r , t 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 connehc9h,n4w /cs bse 4)aocted to the end of string and moves about the string’s fixed end in a conical motion with a constant specwch/ehb 9nso ,a4s) 4ed 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 in3ugb+:q,s:)bjq lk9tnvdvn / uniform circular motion as shown in the figure. The string to which the mass is attached has a njv /svk:q,qt) ld +nb3:bg9ulength 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 i 2w9 uw-b))wsnt*qsb horizontal disk’s center. The disk starts to rotate from rest about its ci-q ww 2sw)un9 bt)*bsenter 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 wit.)up qxun+ktv +a6uxb)n- fu(h mass M = 2.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in thex +u+ ).vpu tax-ub)fnuqn (k6 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 circle, starting at t8;mel7hwtrb2 he top, with initial speed 17.0 m/s. Thertbwl e8;72 hm 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 final speed of the object?

  16.40: An object moves in a circle, starting7z s7uud rvw7b6pfw lpl*6 :*f at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until 7s6bzplu:7d* 7*fupvl wfwr6 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. )*cadv h/p(cf)e qp6anv zl29 The bucket is spun in a vertical circle of radius L by a rope. When the bucket reaches the highee /(d* lc)9h) aa2cnfvz p6vqpst 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.