95.02: An object shown in thdml::bm 4a+lq2dr *y ke accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the objectdmd:lk 4+ylr *2q mb:a at the instant shown?

  05.31: A child is belted i8ipiwwh6ij8xx ,k8v+y av 5n,nto a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. ,p8iv hxw+ 5,x v8nyij8iawk6 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 const 14 kqt:z(*au tgchrv.ant 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 is exactly half-way around the cirtc 1tzaq.(uhgr*4v k:cle 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 constantj1c34iw;ehw6crz1 :sh 4 pmmc speed in a counter- clockwise direction. Consider a time interval during which the particle moves alon1cc jzsi hc4r 6;mh3wmw14 e:pg 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 clockwise with constant speed arounwy:pxa(89eyp z* uhu: 2-f9 xv lmbt;sd the vertical circle shown. Whicb -awu*y:2tp ( ysh9:;x9 vx p8ueflzmh arrow best indicates the 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 oo/05m2bq zbfn z y,9k 0yf/kwstring 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, azkfq y omw9/,nkzf2yb o/b 050t which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speed around a horseshoe-shaped pat851g:v hijhu ah as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acce uh:ghav1i8j 5leration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perfor5x,/ dzfjv d6+zprle8 f3/ rnsc4fq5 rm an experiment with a simple pendulum that is released from the horizontal poq v8,455 fpc dzzld/rjx enr3f+ 6rs/fsition 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 ik.s2s2.m s qh)nen ep0b*hi5 center of a rough turntable as the turntable rotates. The period of the turntable's rotation i2)0eb e2s5. ihsnk.*q mihnps s 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 friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kg puck moving in a circle 5akp8l, a f(jqof radius 0.5 m on a horizontal frictionless surface with a8p,5 fqkaja l( speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass009, ssvf qepm = 50 g) on the end of an 80-cm string rotating at a constant rate of fss e0v0m,q9p 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m withg0m l ozk;5i.k a constant kinetic energy of 128J. What is 0o gmik.5k;zl the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is at4ka;a0; fmn m*og3ekjo- a +bmtached to a 0.80 m string and whirled in a horizontal circle at a constanta nje+3kmmo ofb;mag*-a0 4;k 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 u4 k q;zzeaurbnn0 c.u5/eck;srsa:; 2 niform circular motion. Which of the following 4n szue. crzr;s0 q5ek;ubn /;ckaa:2 statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches ccd505f de5 ffa mass m to a string and whirls it around in uniform circular motion. The radius of the circle is0fe 5fccfd5d 5 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 tghcs++vmn//(d yczh2m t mi+4 o 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 c4zy +m gn(id c+2m+/vts hmh/string when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the 6nc2k 4n-ekgaright. Assume the car has speed v acnn e6k2 gak4-nd 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 constant spe qhy+gg88v5g ted 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 magnitgq+g ht88g5 yvude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle sbi.9kekt5l(w9dl/o3rsj 5w at constant speed. The magnik i9jrds5lk 39btow l/5.w(setude of the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from rest ft (p0n*jjaj*n rom 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 repr0njnj p*t*j(a esent 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 pendulum. The masm *,aw v*42hqzpez3sfs 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 forceqz zhvp,e2wm34s* a *f acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied toy0:oxc 4lo7:dtm5ae *h4fjqx a rubber stopper moving at a constant 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 fre40xc*fto7 a4:hdjqxo:e5 my lquency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surfazhe 4k1a.c: dece, connected 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 broug.4da hkcz:e e1ht 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 kannyx:bb g aj: 96-4j;rl n9lhg mass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. Wha-bj a6n;yl: xhan: rgbj4l9n9t 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 z(j8t/xm 5x n3dpe w j+)+m9fdxhdj/ vat reston a horizontal disk rotating at a constant rate about an axis pz/hjm (d3+mfed )jt5 p x djwn9xv/x8+erpendicular 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 abo0o9:k mgmb1i; y z,ovtut the string’s fixed end in a conica9 m:tz0v biyo,m1go;kl motion with 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 q7n; lso(l 3bev vvt0nif7*l;*prl *juniform circular motion as shown in the figure. The string torev * ; n*lfspl ;v077l*3vtn(bqloji which the mass is attached 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 from a horizh -oxx-1kwyo8rit y 51ontal disk’s center. The disk starts to rotate fi1r1 ytx--58 okhxw oyrom 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 =edcny;k r(0(y 2.0 kg is attached a distance R =1.75 m from the fixed center ( y(ck ynr;0edof 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*pqik lz73,gl*tgwh) in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through ah)zwt pk*3g l,g*7l qin 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, star mn 3fy-qd xp7s70knn89ry g,nting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise thrn37s7 -rxymk 9nngpf,nd0 8yqough 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 kg9(vfw) 3 pteun block rests at the bottom of a bucket. The bucket is spun fu)nv wt(p93ein 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 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.