95.02: An object shown in the accompanying figure moves in uniform circularz l3fnnq5ek1dy12 d9j motion. Which arrow best depicts the net folykj11f93n5 e2dzdq nrce acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates countercloclax-iz ybl)a hw9k- d ;x;yr/6kwise at constant speed at an amusementyaxwad;x9-/ibzk ryhll)6 ;- 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 circular path at constazu8 q.mn why))/(9zv bvcyu;vnt 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 iy/vhyuwcz; )9 8mqvzb )(.n uvs 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 constant speed in a e/y)(oqbquj,9 er q;z counter- clockwise direction. Consider a time interval during which the particle moves along this circular p /;y qobjq9eqer,z( )uath 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 with constant speed around the vertical circ 4ln5q.2itbg6tn k5 *pscjt+1i dm:g3v -qeqtle shown. Which arrow best indicates the direction of the object’s instantaneonbksptigneit j :vgt51 5-.q2+tdlc34 qm6q *us
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a av 7btxu4tde(ly.x3: 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 te 7tt:3yaxd .l4 vux(bhe figure, at which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speed aroun2b, fs:g7 om/gl,,r sp4nxez hd 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 assf,:7,b2x,gr4zg ph/lneom cceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon pw,hs+7*ohdv utl sb52a8. j gwerform an experiment with a simple pendulum that is released fru*j lo vdg5s8wa+ 2hs,tb.h w7om 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 r 9 (rf2 oq(a:suki *;/ aqn1c czohx--ul2sdnlough 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 ca u9 o-s q-l dfcakx12*zhn/lsno(2r: ui;q( is the magnitude of the force of friction acting on the object?

  07.19: What net force is necessary ra+e0f6 0iopib8x n d*to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with8n d 0 bx6*er+0poiafi a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an objecqnc,ei c6ec 53.w0 ogmt (mass = 50 g) on the end of an 80-cm string rotating at a co5qo3c inc e c,wm.0e6gnstant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8o5+ng iy 8*ypjm with a constant kinetic energy npo+ ygj85iy* of 128J. What is the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball isx7 hg yy nl-uys)+2(etu ;ily2csd8p) attached to a 0.80 m string and whirled in a horizontal circle at a constug-icyx)t u7;(l ) 2h enlypsy+82dys ant speed of 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 motio+ ggp35sp4ionm08hsh n. Which of the followio8p54 3mg sgn+ hhi0psng statements is NOT true?

  00.19: An astronaut in an orihn 3/oyk-1rmy5p z,e biting space craft attaches a mass m to 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. If the mass, radius, and speed were all to double the tension rhm ,5z13/ry-yipneo kequired to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of length L tyfv u (3lbc:h/12jdfoubtinei(ym ko9 :)4 -ko which it is attached makes a 90- degree angle with the vertical. The mass is released from rest:ec o9yb /(hu-i mvik(n12ktd3u:y4ofb)ljf 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, 0.fiv82.d u)kak/ nw+ nts dnisee 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 ovts/ukdkw 0n2a)in+d.i.n8f f the car 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 thel r*;w.bioo 3x(hy8wbal 6t.u 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 lu* ( xi.rhoby3alw;tbwo .86of 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 very7nq y (msjj-7c (,;rtvp/ nrutical circle at constant speed. The magnitude of the net forn ;q(uynv sj/7c t(,m-py7rr jce on the sphere

  11.47: A simple pendulum of length Lhasa point mass M releh/lw-hit( cm4c ul.q-gl nh-:ased 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 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 swing- ll tq:/hhm-i-(.glwc uh4cn s at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simple pendulum. The mass is releas zl /*jtpxsp((rus1*ys g w,2ced 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 ne* (upg*zpyt ,jw2ls ss1( r/cxt force acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons bwp h50v 2yxv+is applied to a rubber stopper moving at a constant speed in a h+vvw2h0p5y b xorizontal 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 surface, connected to an ( b3 ysl5 ;ezn6f.t)bcxg+5, r/mzphjk7uyygideal 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 guz r y)bs tlex5mzcnky/7(b5gfh ;j+p6,y3.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 bv 0)yh4+e7py+n(bl n djqw+hm2qt4k4.0 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 lowh pq(kvqdeh4w)t2+ yl+y7nbn+bj 0m4est point of the circle?

  14.23:Two small identical coins (labeled X andY) are u ym d33sd3s4canq)0qat reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance oss3 q3u ayd) nq34d0mcf 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 1s2u09xl4d o1vj9gbs s whr-gconnected to the end of string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length of 2.50 m and forms an angle of ug sb19 vxlg0j4ws rod -9s21h$θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular motion as showfr7q s**9xh zcn in the figure. The string to which the mass is attached has a length of L = 3.00 m and fohcqx9fs r7z** rms 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 isvyk-0(t( n.+cf4h8g ghh0mz e 2i nwml at rest 30.0 cm from a horizontal disk’s center. The disk starts t e+ym2h gghf0.l-(ntn(m k0 4z8wchvio rotate from rest 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 mass M = 2ufe6h:oqyt . ,.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from re. quhfte6,yo:st 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, wi ej:q(k.cfj bu:6nkb2th initial speed 17.0 m/s. The object’s scuej26: fnjb( k:qb.kpeed 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 circle, starting at the top, withne)e6ch l kv29 initial speed 17.0 m/s. The object’s speed n6hkvc )e29leincreases 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. (7o wncjj/ *qqThe 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 qjnc7/q*(oj wfor 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.