95.02: An object shown in the accompanying figure moves in uniform circularl, 6h1 4p7cwt.ah0cm3heqd re motion. Which arrow best depicts the net force acting on the object at the instant show,we 6md0e7hpc 34ahl1 q tchr.n?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwis2yzm7eo(z/uj tp+bi0(,o pg ye at constan p(+giym2oj(be 0,pytzz/o7 u t speed at an amusement 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 mbt;;3 so;n:;kb irfazoves 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 aroub; sto;a 3i ;fznr:k;bnd 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 constauuu8i2lc6e 9 knt 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 around9ike8u u6cul2 the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise wx b4p+4:rxscn0:w b onith constant speed around the vertical circle showb::0xn sn b 4xr4p+owcn. Which arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass cf bo+d)g e 7sodiq(9n,onnected 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 iddqg,7bs9+f )i oen (on 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 horseshoe-shaped path as sxqj-a qlm 5*uzwz9)z/4zbt 4whown with the arrows in the figure. Which one of the following choices best describes ta 4)5-l */ 4qztzqxz ju9wzwmbhe direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon pe1zuh(4o /slghrform an experiment with a simple pendulum that is released from the h/os1 4zulhgh( orizontal 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 )p3h;, u vmc0kuw29vsah (wnrfrom 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 betw(;cr9v 3ahunphkwwv,0 mu2s)een 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 keepu(hk sdzl4ec9 d(9c/nb4li e cu7w:me -p;cn( a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizonta/p:le k((4c dew nz(idc4 7hcuml9se cubn-9;l frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g2 ocw0jb(-;sb7hl mzv ;ou*zy) on the end of an ;jwyuzb2*b ;- h vcoozmsl 0(780-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8 homgc2bpk,/60ks 7cstf*oz -m with a constant kinetic energy of 128J. What is6 ogc -0bpzkc/ht s2,*o 7fmks the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached,gh nu 3/ol2u)ih qbc47uqx:0p d)kgl 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 r/2u03qud,hxnulg ipkg) ch7b:o4 q)l ight. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a roph6ih, w cktu1+ ;j( ku /ud-f2ml91zbpxeeo: oe, in a uniform circular motion. Which of thejpd tb1kuucx-o(he1ez kmhio:lu6+2 ; 9f, /w following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attz(5ui /y0qbbi aches a mass m to a string and whirls it around in uniform circular motion. The radius of the circle ui5b y( i0bzq/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 until the string of length L to which italy)(oka i(/a 4o q7ft 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 the mass swings through the bottom o( aa oay/ti qkf)47l(ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the right.,b*yc2ki+ lxi Assume the car has speed v and the tops and bottoms of the hills have radixy * bkil+2c,ius 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 consta )mj; q:op7f a76cjhxknt 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 best represm;qk hfa)jco p j67x7:ents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vu c-je tjxq6,gb195k *i;o,jvgwv itpc s,k3-ertical circle at constant speed. The magnitude of the net force on the sphe 1t evgt, ii -p*,w k5v,k qjogb3-cscu;j96jxre

  11.47: A simple pendulum of length Lhasa point mass M releas6)vk82+ -hf hyzroh4yknd-yc ed 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 maf8ko)nk6-4yy d+ c-hvr zyh2hss. 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 stc4(1nhnjwqt55,wf n i ring 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 string (T), the gravitational force on the mass (W), and the net fo ft,jn(wn5i 1h 5q4ncwrce acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal 0ovc yz3 ihr( ;r(w( d*fl5wnvforce of 5.0 newtons is applied to a rubber stopper moving at a constant speed in a 5lhdz iow ((y v0(crf3rn vw*;horizontal 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 ideal d)*d ; qq6 8iyei9ds a6ah3dibhorizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and hos;e qdi yi8d9i)dadh6b*3 6aq lds 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 in a vea6kxt0nb0 z am8f0xm.pj w) ;ortically-oriented circle of radius 0.75 m. What is the net force acting on the mass whzab06k j0wfo.mp 8m )xta0nx; en it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizontal diskvhrdp:;tmwx3 e ;5j0c rotating ath5vdm0 pxer:3j ;t;cw a constant rate about an axis 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 string and moves abo;t-6n)-tjczr9g8 w va9bd xk q)c(xhbut the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The 99gxctrh d;aqcj z)kb--6bwtn 8)xv( 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 q5r: nx4.u5 jeey9jx 3b/egxzuniform circular motion as shown in the figure. The string to which the mass isb9jru54 xex .nezy: 35ejxg/ q 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 objecu9 75gc dwlxm *d08yobt 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 cons wc5dd0m897 og*ybuxltant 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 di) kgi-9/ g3hfij4isyx ffc 8s-stance R =1.75 m from the fixed center of a disk as c- jg4 kffh)ix-y /i3g8 iss9fshown 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, start ki* zo w-on39x3bwkf xj+(080gso hccing at the top, with initial speed 17.0 m/s. The object’s speed increcgcos3-of 9ko(z8 w *jhxb0inwxk03 + ases 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,xzbhni-w7 njg(k15e+y (j1vw starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly gj1 +z5bvn in-7exj 1(whw(yk 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. 3cxig y.* 23bmit: wso(7zx17qok j diThe bucket is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest pmbx(1ocsijyt kw 3.:zqxo72i3*g 7dioint 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.