95.02: An object shown in the ac. lzwjv d87hqw * 4(r0haolcm0companying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the instant shown?70 c8 w0 4hj(dhrlqmwvol.az*

  05.31: A child is belted into a Ferris Wheel seat that rotates coqptd2f.zp2 ft4 - 7npiunterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total p qpf2d2 p4tn-ti.f z7force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path at constrqj5 hg1;0 3ju.akk cgant speed in a counter- clockwise direction. Consider a time interval0g1 gq.hc kura5j;j3k 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 cowia h62g./6cro zhvb,ntinuously 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 pointvw/i. 6oaczr g 6hh2b, 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 v yc6av6ec.: zy1y-ix dertical circle shown. Which arrc y 6-.a:x6yvi ecz1ydow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small ma u c9 rr5j-)i8mqhdqss71z pn,ss connected to the 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 sho1i, 98pzm-jsrq hs7)rndu5c quld she let go of the string?

  15.23: A car moves wity0m(7donvm 4vh constant 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 acceleration7yv nv(4mo 0md of the car in traveling from Wto X?

  08.35: Astronauts on the Moon qrqp 4m3lfi): /ux5kn qqh)j(perform an experiment with a simple pendulum that is released frq: 3)(k/r i)h4m fxq5jnplqquom 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) poinm ysi6 f.rc elwo*p 5s-xb:(ox,jr2u6 t-like object 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 coup:6f rbw yjx5e,-6icso(*s .mr2o lxefficient 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 dvvy ,ex: ri7)+sojr 5kg puck moving in a circle of radius 0.5 m on a horizontal fsjrvodr:,xvyi5e ) +7 rictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an objec;j, vz-lw znahy.,5vo t (mass = 50 g) on the end of an 80-cm string rotatinjlvz;5hy -v,.zo,wn ag at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path p.o )xtz;2v-,hg yytutlx3koe / e; t1of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force act l.- x2pov/3yhok ;t); zgtet e1xuty,ing on the mass as it moves?

  96.24: A 2.0-kg ball is attacheun+ 9p)ge+.n ih xdb)td to a 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 wo)u9)+ +hebi nnx td.gprk done on the ball during each revolution is:

  99.22: A child whirls a ball at the end -eo r -(c.ioikof a rope, in a uniform circular motion. Which of the follo- -k.iecir(oo wing statements is NOT true?

  00.19: An astronaut iyptrn0oh2)r*w gu6b- n an orbiting space craft attaches a mass m to a string and whirls it around in uniform circuhn r0y2)tpbor*u-6gw lar 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 double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward uu02mndc rx8. zntil the string of length 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. Wh xm.2u z8n0rdcat 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 hill/eqy5c nkn6n 9y 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 of9nqyk 6en/c5n the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at acz68s u,j5lgn 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 thez,csgj65u n 8l 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 constnm 7gb/p2s.j mant speed. The magnitude of the net force omb/ mngjsp2.7 n the sphere

  11.47: A simple pendulum of length Lhasa mxc/c q51*eo cpoint 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 on the mass (tension), G represent the magnitude of the gravitational force acting on the mass by qx*cc 5oe/1mc 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 issh;(k ydx4(. anqo eg6 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 acting on the mass (F) when the mass swings through itss(ehd.(6xgn;k yqa4o lowest point?

  04.41: A centripetal force of 5.0 noe w4j4v8 pgv1ewtons is applied to a rubber stopper moving at a constant speed in a horizo1v o 844jvgpewntal 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 rest on a frictionless surf.fwc vk-myqln/33 d pp:nmmf)g kd/ ,:ace, connected to an ideal horizontal spring d,lkwp :ym km)n/.3: ndf qvmpcf3g -/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 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 of 3.24 m/s 1sq)veo2wh0v in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it s hq1o)vwev20is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizontal d-l;bt)n16e;e aji3gd 0j blwiisk rotating at a constant rate about an axis perpendicular to theib0njb1de3 6; gllw;tje) -ia 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 an9dr*0hl rv*w y66azt q6amz+z79fecqd moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s.zv6 fl7 rda+h9tqe6z9 w06c**q yarmz 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 figure. The m b18oc.ey)uso+,hv dstring to which the mass is attached has a length oo,hy c v 8.b+esm1u)dof 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+ ,hwn3d/),it4 mvpcx wpmldc- 7/ igc 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest abo+wipn )w/ c/m gm,-vdi ch7pl3c4 ,xtdut 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 mass M = 2.0 kg is attached a distance Rv)h9ucja+vz e( i+c, z =1.75 m from the fixed center) ev+czah+cj 9v,zu(i of 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 top, with9tcj- +ctp6 rc initial speed 17.0 m/s. The object’s speed increases uniform6cc+-tc p9jtr ly 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 t,sl,fz5*slg circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise thro5fzl*l, ,tgssugh 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. The bucket is s 3 lq j 5md-6-km0:0fwvcfoynhpun in a vert5kjm0fl3o-v6nwd hy- :0qc fmical 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 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.