95.02: An object shown in the accompanying figure moves in li,*sr*-jeji pgw zh+j,up*2 an9 1xa uniform circular motion. Which arrow bsu**jgjn pa ir91z,2 ,li-x ah+jw*ep est depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seatpj4j 1 2v.bl;coy6jvp that 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 the seatc4j2boj6 ; 1p.jvlypv and belt?

  08.14: A particle continuously mour ;f1/ cnh:yhves 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 point Q. Point Q is exactly half-way around yn1:rh/uhf c ;the circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in bc **h.o1irzj4h eh3ba 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 point Q. Point Q is exactly half-way around the c r.e3ho i hb1j4h*czb*ircle 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 thc5k2 xb1: g8 3ocxrmmle vertical circle shown. Which arrow best indicates the direction of the object’s instantaneou13bm8lg roc5mk cxx:2s
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end jga5 a pvd9:uil ,q29mof 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 should she let go of the sqml59jaup: a2d,9i gvtring?

  15.23: A car moves with constant speed around ofwh 5k5 (up6ghz9ge g-1k;ti 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 g(1z6wohk- pgihkef5 tu;59 gacceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experi l81 hn szoz5(4we/sqwment with a simple pendulum that is rele5o /18zwq(lwzsnhes4ased 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 rough)1qz )sanyzph8op ( *:3akp;w wlay+r 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 frictionaw3)p p k phwnoyz:a l1*yqrza8(s)+ ; 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 1cn qt5-df7r fl5ez4xcircle of radius 0.5 m on a horizontal frictionless surface withlftrx d 5154ze-nf cq7 a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration *yh.2vt+cq pta8,fsfof an object (mass = 50 g) on the end of an 80-cm string rotaf,+tvcf8 *h.2qtayp s ting at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of r il*pmv m fcyy*-9iw:aw, ;ex-adius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as it movef, *w9exw i:-*yply;ivmmca-s?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirkx 1h (0:dbhp8jh2mxlled in a horizontal circle at a constant speed of 6.0 m/s. See figure to them( :0xhh8jpl1bd2kx h 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 uniformla0ak s3*22pxrvcx 0l circular motion. Which of the following statem*vp a0la2 3xs20x ckrlents is NOT true?

  00.19: An astronaut in an orbiting space craft attaw +g. td:rlqd+1iyd e0ches 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, aiwleyd1r.:0gq+ + ddtnd 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 pul;r o7it 9 tmliojb81i:led outward until 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. What is the tension in the string when th9: 8;7iooimirljb1 tte mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see3qkz 1;po pn96gb(lrn figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvaqgkn3obp r;lp(z 96n1ture R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill ad03vcj++fqj c t 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 besf3cdvqj++c j 0t 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 constant speedbe :yot1zfln0(3vi5 er i (1gk3zik+r. The magnitude of the net 1zeofvtrki giliy:b+znkr 3e (513(0 force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M rex0l) ier).gq0 6h6zuwo8nvw kleased 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 relatiq6li x)0ohw6wvgrku ez 8.n )0onship among these forces when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected top 7- 8aosjymenv4:d.knef0 17ona db* a string forms a simple 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 stris8d4j0-fe1o ndk77b an.*pvymn aoe:ng (T), the gravitational force on the mass (W), and the net force acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is appliecs,9ske(8aq rhh0y *xd to 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 hcx*0(a q, 9seksyh8rhappens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on; ki0 nbiuhc6p--ll*e a frictionless surface, 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 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*-eln;kp-0l uc i b6hi there?

  12.22: A girl swings a 4.0 kg mass with a constant speed of 3.2b9f:fhis;7x6b0zot)k ghko-4 m/s in a vertically-orieg kb9;t7)ikf0hz h x-obsfo:6nted circle of radius 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-/v*fb1td gcp2+ f pnb (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis percptv-+ 1/d2f*gf bnbppendicular 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 c/m*ws 5 e6aqluw(llca - ar58donnected 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 strinw8*a m5/ 5aqw-s(6uale crdl lg 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 ids q; d27 .da-lomze. 4si(qcks in uniform circular motion as shown in the figure. The string to which the mass is attached has a length of Lqdoi (ql2m. 7.4 es;ddcs-azk = 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 objec-e6t*uf2g v t90l wh,wdff sx;xv5 ,hrt of 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 a constant angula- fxd,*lvt t9f5wvsh0u;6gef w ,rh2 xr 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 attac9; .yb k9,jieqeiw y/dhed a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from /9ykyqij ,9w ;eb i.de 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,k 3h:l)lq*dz 9kw jw0j starting at the top, with initial speed 17.0 m/s. The object’s speedzlqkj9):whjd0l kw *3 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, with initial spej(uek dhs, dr+c64 w jt56q3wqgl*cm)ed 17.0 m/s. The object’s speed increases uniforml*r63ec,s)dm (wcg+ut5w6jqq d4kh jly 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 buck3g3 jo-f9yuel/alyb 3et 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 for the block to remain in pla3o /lya3j g9ful3b- eyce 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.