95.02: An object shown in the accompanying figure moves in unif* nk9jx pjb.2horm circular motion. Which arrow best depicts the net fo.k2jhb9 xpj*nrce acting on the object at the instant shown?

  05.31: A child is bel*) ysvcal:ec8+udfk(-0nmq 4e eu zw6ted into a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exer-cfcu 6l ( *qnea:w)se8d4zkm0vuye+ted on the child by the seat and belt?

  08.14: A particle cont3 6 0gvg+5eb4ewuh 2c,skeepvinuously 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 circle from up gh5 vk+6ebe, g43v2w0cseePoint P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a h-81.e t igmnopwh) 1ucircular path at constant speed in a counter- clockwise direction. Consider a time interval during which the paruo i.wptn1hmh- e18)g ticle 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 aroun8,kp*mk dllv,m3w ot7d the vertical circle shown. Which arrow best indicates the direction of the objet,mw l*, l m8okvpd73kct’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to t w80auncwf /4hjil8tag 5y(h:he 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 point labeled P in the figure, at which lettered point on the path should sh:utwjfw(8/hl5 08gi an4yhac e let go of the string?

  15.23: A car moves with constant spegp..4nundky;06 tz gb6w3jb 3k 3y*dvsq ikv+ed 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 the car gbn w q4g iyj.k660 u33dk .ktz 3+pvv*ybdsn;in traveling from Wto X?

  08.35: Astronauts on the Moon perw/5 gyqbeo/e*oio7te2r/w6 t form an experiment with a simple pendulum that is released fromoe/56*w r2e/t/ tbegywi7 qoo the horizontal 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 5:smp 5q48 r8wp z2o7q me,si6oshtvl kg) point-like object rests 2.0m from the center of a rough turntable as the turntable rotates. sws5 qv2m:6,m8 zs7q5 eol8ri4o tphpThe 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 keep a 1. 0 kg puck moving in a circle- 7hcznly-ub.fgj/: nil y20s .6k hmq of radius 0.5 m on a horizontal n m0k s6yguqh:. l.2fnz/ybh-cijl-7frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal accelu vtz)k- p/o9weration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 t/-uvk9t)wp z oimes a second?

  09.24: A point mass moves alonzor5 unis7je6r /uv65 y) kjc5g a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the neusrj yj)76z vie5u5ornk6 /c 5t force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to 23crej, t0:m -t)kwo rnw8je zgerg24a 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 done on the ball duri2eron4 -cj,rm zjr8ewew2)g3gt:t0 k ng each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniforl+ .ox-0 b i d8mqvj.xemtc0q(m circular motion. Which of the following statements is vc . 80idqtb+ej0 mxox-ql(m.NOT true?

  00.19: An astronaut in an orbiting spcffy 7hp4j- a-ace 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 doubl 4c a-j7f-fhpye the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of lengtn-h -kpb,wun /h L to which it is attached makes a 90- degree anglew-/u-k b,npn h 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 travelidjof *9amc- l(ng on a road 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 ofol*cfa9-djm( the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hrk-q/0hzdsj++ yfhd 84sz hq3 ill 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 exekdrh3qy4jds0fqzh8 /++-s z hrted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at const, wd3zkg2j4qauffi3;7qiv4 tant speed. The magnitude of the net for2git duq q34z;7v3f,j4af kiwce on the sphere

  11.47: A simple pendulum of8s9+8d6 m9ga t0xv gs+iphurc length 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. c+0 su8giamxs8+t6d rv9hpg 9Let 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 pendulum. The mass is releases1sr/ s 6yz8mt/qmr,gd from rest and undergoes simple harmonic motion. Which one of the following crsrmz1 s/m t8yg6/s q,hoices 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 newtons is applikfr l:,tfpc m a69+i)led to a rubber stopper moving at a constant speed in a horizontal circle. If the same 9t lc:pl6+fk ,im) fraforce is applied, 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 rest on a frictionless surface, connected to tlrirf7cgg4: q/ .:f lan ideal horizontal spring that is upstretched. A person extenqfg4 g7rfl:r:l t. /cids 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 4.0 kg mass with a constant spek-p93 sl nwsm.ed 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 ws n-ms39l .kpit is at the lowest point of the circle?

  14.23:Two small identical coins (labeled s5qc-(3 nsq l,v+4 ilnfq8lyd X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicul-nlvcq( 8ni 4 yfqls+3l5ds,qar 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 connected to eumil,0xxo..1bb1r j the end of string and moves about the string’s fixed end in a conical motion 1 bb.x,1 .limuxojre0with 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 as6yl x6nihv5 *h shown in the figure. The string to wh *yhl56hxinv6ich 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 mavv ;:ng:/m,vhruj j4c ss 11.0g is 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 acceleration :vn:rv,j/gv4;huc mj 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 distanc m8 .p* i)jpoiasl 7;d/cce4cwe R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from r.4ms* c;p l/iwdi)jaco ce8p 7est 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 zyy1kszya2 9 ;17.0 1sa yzyk ;z2y9m/s. 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 final speed of the object?

  16.40: An object mov2xm -q;1uhctlf; 3*zkas 5bqces in a circle, starting at the top, with initial speed 17.0 m/s. The ob-hbm*cc3t;q su1 ;2fxk5qa zlject’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 ressy)o jq::2vf tts 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 the bucket. When the bucket 2::y)otvfjq sis 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.