95.02: An object sho 3em;iv s 1w-y0bm3:jmkfno/fwn in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on thev10: m e3fy- nikbw/ms;fmo3j object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rwmicux 1 n.r)g +i5r-uotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted 5r1ui ngxuwr)+m c-.ion the child by the seat and belt?

  08.14: A particle continuously moves i4s.u. gfz ejsjj90r;xn a circular path at constant speed in a xusgj.z; r4e j.0f9jscounter- 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 Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular path -+jhxrkl d. 824 s0opyrtz;vwat 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 a h s-x8vtdwlrrj.; k4ypoz0+2round the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise witaoevew pt*+ .gn 1x/s,h constant speed around the vertical circle shown. Which arrow best indicates the direction ofv.e ,wes a*1+nxt /ogp the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small m itfp5l ek-1w:zjym1c p8 *qp,ass connected to the end of a string counterclockwise in a horizontal circle above her tpz 1,q8 -mcjylpw pf5*ke:i 1head. 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 she let go of the string?

  15.23: A car moves with constanqp2b( n kod3ur-b+ad 7t speed around a horseshoe-shaped path as shown with the arrows in the figure. Which on+d23b pkbna(-ord q7 ue 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 2)arjfhm dy4 +e1)g ki9hahk ;Moon perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the mom 9)kmiyk+;rafg1)h4j eh2hdaent 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 rests 2.0mj1smjd40teo)j :*trjd1 c6 +a,nlwxu 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, while41+wj tc 6 ,jdmx:r ojta1jl)n0d*seu 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 9 q4+)s) khl 9gqcq7yyf ikg(v 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface wit4gi gfs)ly)y vq9 h+9cq(qk7k h a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (maez+vw a+6g eh24z wylxn0b.(hapb * +hss = 50 g) on the end of an 80-cm string r.+6h42eyp+xehw+ a lhbb( vg zza*n0wotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a ho2kw55cxs ;tks c:0 ksprizontal circular path of radius 0.8m with a constant kinetic energy 5k 05:kwtsxp2;ssckc of 128J. What is the magnitude 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 9s8c)ezd2 mbao7*dfmstring 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 f7ocds9dbm ez8a )m*2during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular t7p:ikoi 0terrk ag4 e v0e9ob23+. bkmotion. Which of the following statoat039er pigk+04 2r vt7be.:ok eibk ements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m toc)/w ofn3vv-j 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. cvv- wo n)/f3jIf 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 ouoq7*t;x.h boj,io z7xtward until the string of length L to which it is attached makes a x tq oz;xjo*i.b,h77o90- degree 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 terrain, see figure tjc 78:tc6 avoga*6re bo the right. Assume the car has speed v and the tops an baore* :gcvc686jta7 d 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 a constant speed of 123 ( )xf0)sznzap *tr3tiiv2vz.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 thet zv zspi)23xvnz*0)(t3ar if 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 a vertical circle at constant ixiww0yc2253b wp6tk speed. The magnitude of2xybwiw25 k3cp w i6t0 the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M relev/s rv8axsawd;x *0.x ased from rest from the horizontal position shown. In the absence of air resistance and friction, the mass swings through the arc of a circlxaas.s8vr0x*w;xd v/ e. 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 simplg-kzc aupy2/.q7zke 3 e pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude 2ek y ca.p/kzq7-gu3zof 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 al )p3,hbtfmi8pdkobj7;0j ,cpplied to a rubber stopper 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 fp 3,jh)tc md;b opi8fk07,ljb requency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless sel *1sb, sdba+t jao8f33 36lyzxgek6urface, 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 10 N force. The spring is brought back to equilibrium and the mass connected to it l6o3g6 kb*sxat33ey 1l +j,fad sez8bis 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 of .(wudl(4 htrc3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force(luth.c( 4d rw acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston r(nugoc :*im;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 coinsn *;( um:ocrgi 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 the end of string and moves abou2d.ymf 3l ey*zt the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string.dlyfe*2m z3y 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 as shown in the figure. The (/3syrm a/ (9x0u abq nfmbrw/a,jp1qstring to which the mass is attached xwa1r9b aq qbas3up f0((/ymrmn,j // 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 mass 11.0g sdp bm-6.4 k zrr5bha.is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constan.zbb-dhmr p5asrk . 64t 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 dis e9oqlh9 k.7yg4+xz qy -mz+hstance R =1.75 m from the fixed center of a disk 4oyl mxz-q+ +z.hgqyek79s9has shown in the 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 iwa kzsbl3 ;e74dc*zs6 n a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly unt43acel6d; sz 7kz *swbil 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 circl ia6;6gwufm 3 ,z0+l ,wnbowfye, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle ozw,ub6fyglm6;io + ,0af 3n wwf$55^{\circ}$. 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 bottoglj4ojn )h69h*- zwk,,3 v- nxycs ascm of a bucket. The bucket is spun in a vertical circle of radius L 4v j-zy9x,cw,-*ahng3cos)l6 nsjkh 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 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.