95.02: An object shown in the accompanying figure moves in u8sk nj or*7.apniform circular motion. Which arrow best depicts the net force acting on the object at the instant shownn8ak rs.jo7*p ?

  05.31: A child is belted inv;mh24 fv crdk/ czo04to a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total forcz k/v2c h04orf;vm dc4e exerted on the child by the seat and belt?

  08.14: A particle continuously mo ra ub1 5piuz(wawgw. h7tm:-0ue h/7oves in a circular path at constant speed in a counter- clrb1 7zw wh w(tup7h5 g/-0uoum :aeai.ockwise 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 a dqf2ig0um htm ut3b1 51tn88at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular path from point 8325gm m tuibafq1ut dh0t81nP 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 aroir9 :yi h39jj)a e*qib,va) tiund the vertical circle shown. Which arrow best indicates the directio99) , a jteqh3jiir)iyba:i*vn 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 countercm 563p s g*+vevyj3jztlockwise 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 masy6g5v j3et m 3j+zps*vs 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 hoa/ *ree v2g;4bpbeh9 rrseshoe-shaped path as shown with tb/2 h*a ;ee9pr gbvre4he 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 Moon perform an experiqw)p w ;y5 9lzqenwq(3ment with a simple pendulum that is releasn3 qlwwy( wze;q5p q)9ed from 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 kg) point-like object rg0/ lxy * jnxve;3+f b:rplyb7ests 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 static friction is 0.80. What is the magnitude of the force o fje 3 /xg0yryl;pl7:bvn*b+xf friction acting on the object?

  07.19: What net force is n*hm(i a5/ymx pw mc91jecessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a sp1 x5a/*m iw mcm(pj9yheed of 2.0 m/s?

  05.03: What is the centripetal acceleration of flkx19zv uz. -an object (mass = 50 g) on the end of an 80-cm string rotating aufx 9lk. 1-zzvt a constant rate of 4 times a second?

  09.24: A point mass moves alo,lp7 mfdn6qh +ng a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitu+6 dfnqh,m l7pde 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 string and whirled in a horizon+g22t v2umr lhtal circle at a constant speed o2hr ugl2v2 mt+f 6.0 m/s. See figure to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular /izi,ly fvj(yg0b:- ymotion. Which of the followily y j:,-yviz0fib /(gng statements is NOT true?

  00.19: An astronaut in an orbiting space craft attachesn+tdeb9j3j)8ftqgq lu iu 7o ,2wf ()t a mass m to a string and whirls it around in uniform circular motion. The rau f3dq(,etwtou+t8) j 9)2b fignqj7 ldius 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 double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of length L to which it is atn q qto3j-lk)(tached makes a 90- degree angle with the vertical. The mass i jnl3)qokq -(ts 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 trave jn2pf r2 hxkxx0bb xh2.0v;m8ling on a road in hilly terrain, see figure to the right. Assume the cax xh;jprbf vx82k00.mx2nb2h r 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 a consi*ymb( q,4sv lm 1e-eitant 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 indicamie -1,ml qi4 sey(v*bted 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 a vertical circle at bkdz4wec vv011aq nd4sxpc) 2ez2+*lconstant speed. The magnitude of the wv pv+ q *0lz4dz2)ec2b1c1 de4aksxnnet force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from re tgl f +1))fvcavqdc7fq-,d 8nst 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 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 cho-1tf d7 f+)qccg)fqad8 nvl,vices 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 releasa9r p pq)1ywx5ed 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 acting on59) ryxq1pa pw the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a1z mb /06lzra2)n9 gy2vqrpyy rubber stopper moving at a const/yl2pr6 maz 0)2bn qg1v9 ryzyant 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 stopper?

  05.28: A mass, M, is at resmytrzl yo f/1p/z( x**t on a frictionless surface, connected to an ideal horizontal spring that is upstretched.*ypz x(trf*o /1y/lm z 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 ,,xffszvo)v x gvbbi)(,, )t y;eu;dp 4.0 kg mass with a constant speed 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 it is at the lowest point of f)b)(d p vxxs;v uzvt)bg;,oify,e, , the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizonu. r1 (.9q( pydbvoxq5j7zqw vtal disk rotating at a constant rate about an axis perpe. vd (xo qpq9q5w.vuy 7z1r(bjndicular 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 the end of string and moves about the strgu+u-(*rhbnps8(wu zx)fe9r9i h i/ a ing’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length opr (z9h8/e gf9ihsw*n- ba)rx iuu(u+f 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 s 9siau 8fk4o4ahown in the figure. The string to which the mass is attached has a length of L kfao a us44i89= 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 horizf24.s)kprwb b,xgkl 5ontal disk’s center. The disk starts to rotate from res kf5.xrbk 2w),lp4b sgt 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 masse2xi; l7:xyoxa4rj1u M = 2.0 kg is attached a distance R =1.75 m from the fixed center of x i;:xleyr7a4oux21j a disk as 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 in a circle, starting at the -q19utjdsmuyp .q-a8top, with initial speed 17.0 -satqjuu9dq. - pmy18 m/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 moves in a circl3u5fe1zk/ sc (c8/oqixyc sm0e, starting at the top, with initial speed 17.0 m/s. The object’s speef /o31qz0scky cexi/(c u5sm 8d 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 rests ;zp) qzmrkjb ifx2uc66;o8:h 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 i if:b;q)p2um6oj 8z6r chkx;zs 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.