95.02: An object shown in the accompanying figu99 tw 7nqohyi9re moves in uniform circular motion. Which arrow best depicts thenw i9ht79o9qy net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferrimf koo+9li g3n7llw44s Wheel seat that rotates counterclockwise at constant speed at an amu3 o94wlmlnigk47 of l+sement park. At the location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circ t5813t+hdw di rz pu9i(xcx9eular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along thhrpxdc 39(z ue18i9 wt5dix+tis 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 c -)gz-3d htvieircular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this ve g3zd -)ti-hcircular 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-g/r b 95vqjrzc;rn-u dspx-8 with constant speed around the vertical circle shown. Which arrow best indicates the direction of the object’s instantaneous zpxn--8uc9qrv ;j -drg /5rbs
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string counterclockw dv.nai2hsxgm3si+ )8t40dvj ise 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 pad id0 3+)h jx.ntgaisv82s4vmss 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 horsesho5 nun )donh89he-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of thh on 9nh58)unde average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on a5bsi+ k zmaapf; -q*8the Moon perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the diagram wit*8s am+kiz5pabaq- ;fh $0^{\circ} < \theta < 90^{\circ}$ , the total acceleration of the mass may be directed in which of the following ways?

  03.19: A heavy (2.0 ks,) fe 5kdxnvg:bx w,4ipw/t ;g) point-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 coefficient of static friction is 0.80. What is id,btpwnx4x :vk /); ,sfe5wgthe magnitude of the force of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kg puck movinkz.:r3+0l mpmgrl yz0g in a circle of radius 0.5 m on a horizgr y+0kzm.mlz0l3 :prontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the ce hk,w/i ir picn*,z7p9ntripetal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate o7w hiizcp/*,kp n ,i9rf 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.nb2)r)tm 2 9*dusu pmy8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on th9*mrt2bd2ym)usnp ) u e mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled in a horizonxwwa*bam278mp9 j j9xtal circle at a constant speed of 6.0 m/s. See figure to the right. The wor27x9 aj*j8 awpbwmx9m k 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 motioncfqvc77uvd 3g29nyv5o/ts 0 h. Whichn 3q 0o/9svc yd2uv t7fcv5g7h of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a 648kp+z9rdmllg;sn u 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 double the tension required to mpl;89ugzksm ndlr+4 6aintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of len(dpd .0t6fni*6nrh ci gth L to which it is attached makes a 90- degree anglef6dd(h 6cni*p 0itn.r 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 travelin iz7opcu, .a:fn1 z3fsg 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 of the caszc7:.1fz, a3 noupfir is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0 m/s. At t/riwyzl, i0)mfy7s 4p99rx fy he 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 oz7/9y4)i frp lr,0wmixs9yfy f the following choices best represents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere yzelpbz:,0ki,wwxe: 07k0k n is moving in a vertical circle at constant speed. The magnitude of the net force xebz, 0pwkk we:70,knzly:0 ion the sphere

  11.47: A simple pendulum of xs0z+c33 orkmlength Lhasa point mass M released from rest from the horizontal position shown. In the absence of air resistance and friction, th3+oc kmz0rx3 se 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 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 pendulu 2h1cg.e e(qvrwmoj95 m. 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 force actin j1w 29o egh.5rqm(vceg 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 stoppe u( , azihek6y:5f wywp*e0l7sr moving at a constant speed in a horizontal circle. If the same forwk a5h *lfy u(ie0 y,zws7p6e:ce 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 an izl hypp (008vzsmo.l/--diap deal 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 is now doubled to 2M. If the spring is extended back 30 cm from equilibrium, what is th-z0sv0p.-ohzy8i/map pl ( dle 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 spee -42/enjqnb:o6r e4un/gjrwbd of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. Wh noej64-24w/ :e/n bgjbrn ruqat is the net force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are atm)lep) gnjp l0( s/(7q ,ztphi 2z:egx reston a horizontal disk rotating at a constant rate about an pg 7t)j,he lqm(nelg)(z: p /20sz xpiaxis perpendicular 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 sbd1bp l5nzoeb 1.t2 x*tring and moves about the string’s fixed end in a conical motion wpd*tzx 1b.1lb o25ebn ith 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 as shown in the figta vyv5pg3whc+ oqbx t))k,6o*yo 9;dure. The string to which the mass is attached has av 3dhpvbkg9*y+ wq a5o,ox;tt6)c y)o 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 hle /acwyycq xt-5;+,vuy.8 wof mass 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 5uwyy,q+x8c -y.hwt e/c;lv a 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 R =1.75 )b2qmgxhgb 4+s/:wie s 1; ibum from the fixed center of a disk as shown in the figure. The disk starts rotating from rest witui)bx mshgb/ i;b1+ s42gqe w:h 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 ;d1gpgu)et7l at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until pl;1) gu egtd7it 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 circle, starting a8r-liu e8*9;tgfcgc.+bp d adt the top, with initial speed 17.0 m/s. The object’s speed ina88b lp+.g*gif-cd9tr cdu ;ecreases 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 at the bottom of a bucket. The bucket v0uq tr7-/mne is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest point -07 u t/qemnvrin 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.