95.02: An object shown in the accompanying figuw2e(y4yk76v sext7 b ere moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the instant shoy e exkyvs627w(7bte 4wn?

  05.31: A child is belted into a Ferris Wheel seat that5gu0 9b j)irjf rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by th9 fuj)b5i rg0je seat and belt?

  08.14: A particle continuously moves in ak k ibyy4c34s) circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves y4)iy k3sk4cb 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 at con u (v+0a8c uq4i/huqogstant speed in a countacuiu / hv ug8qq40o(+er- 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 acceleration during this time interval?

  15.07: An object moves clockwist4p8.g a)c4 dv d.ut;i5h6+auzthczie with constant speed around the vertical circle shown. Which arrow best indicates t 46hh g.t4i pdzz.8t;ta)ia uvucc+5d he 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 string counterclu)onb )ds 5z .ieu: p+.yiv8mxockwise in a horizontal circle above her head. Th nzm)x ui.e+)8.:yi vo5pbusde 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 constant0 -ubvq* egzc* 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 the car in traveli qb-v*0e*gzuc ng from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendd.1wx pkaw3a-:7na 7- dsu trixshk4:vsvq -,ulum that is k:7s ,t-wpsdix r qvs7ah -:uv3aan.1dkx4w-released 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 rests 2.0m from the center of a ro x ndw2lwr08l,ugh 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 of fricti wr20n,wx8dllon acting on the object?

  07.19: What net force is necessary to k0jy ti:es 1bj0q02wgaeep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionljbs0g:a0 yet2wi0jq 1 ess surface with a speed of 2.0 m/s?

  05.03: What is the centripetakb9eobwu axk. a+ot ( )-r/ds)l acceleration of an object (mass = 50 g) on the end of an.)rd(/kx -tos ea)o +k9bbuaw 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves alo 17-kq dlftud*ng a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on th*1dlft- k7 qude mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirledvd1gz2y ca;- 9y j7qb1ovl)wz in a horizontal circle at a constant speed of 6.0 m/j ycwzl2 7ba-voyv1g q9)d1;z s. See figure to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball uf:- 82qji vemjm,ku:iel ,g +at the end of a rope, in a uniform circular motion. Which of the following statements+je-ivk :e,,um ijg8fqm2lu : is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a string andh(8k fy*nvp9q kkf9u4 whirls it around in uniform circular motion. Th8kv* fupnqhy9 (kfk4 9e 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 double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of le*, fg y9rqmh4qd ;j8kmqkyp7,ngth L to which it is attached makes a 90- 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 thek*m8,dgfqjq 9k7 4 yphmq; yr, bottom ofthe arc?

  94.15: A car is travelingm / tjfaxx59kdpwt:, d2t4nk: 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 n2p :9txjdxdwkm4,f ta /5t:k curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car mov.z ldif4 5zv90 hz b6i,to(smses over a hill 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 magnitu(0o.btzs,6s lh zvi mi4d9zf5de of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circjibpd;*8sc sey3 4i:ile at constant speed. The magnitude of the net force oi:dic4b yij8 3p;sse *n the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from rest av ln3+; , )wkqlh(pt7pe)ak efrom 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 choices describes the relationship among thpk )pl(q awa+,v3 elhe kt;7n)ese forces when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simple0n;k r:sp7lm9ke0 z mu 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 pulnm:9s0r0;k z emk 7force acting 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 stopp:gm onwd3/cw m58u +roer moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made 58+d3:mnu cwo /gwom rsmaller, 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, ct.w-2rvuh3nxlc m a )i3c3r5f onnected 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 bahrm c t -3w5fuxcvr2i.3l3)nack 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 cr do..bj ;6qr; b;wirronstant speed of 3.24 m/s in a vertically-oriented circle of radibq;i;6r;r.jw b o. rdrus 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 (labeler,wj-dr 7koyno1 s*+kd 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. +o71,r dkjsrw*-k ynoThe 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 anhpi 7bu 3fb3k4d moves about the string’s fixed end in a conical motion with a constu33hb74ipf b kant 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 as shown in the x2(rcwz q 0fz3r i5u:cfigure. The string to which the mass is attacz2rcr ucfqw i3x:0(5z hed 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 is at rest 30.0 cm frcvfom1vx**lv;cd u- 2 om a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angular acceleration ofvm1c* ux vc-lvd; o*2f $4.50 rad/s^{2}$ . 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 arg:)-*4oic0y q i7ptk h 3vzk4cow5pis attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts r pi: 40rtq z7c)ocp v- wk4igyoa3kh5*otating 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 spee moyk6uv h- 264ov7whb(q ,ztxd 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle of v7u(-too6, 2 x 4qvbzwym6hkh$55^{\circ}$. 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, stajrvgb6q (b*o 5rting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through a5ogb v*6jqr(bn 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. The bucket is spun h3 b45g9o2 q,gxq7 elk 3gbgaain a vertical circle of radius L by a rope. When the bucket reaches 3ahegl3bg ,x 7a4g52k 9bogqq 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.