95.02: An object shown in the accompanying/u8b3vaqy6 sw figure moves in uniform circular motion. Which arrow best depicts the net force acting on the obj6w 8a uqb3ysv/ect at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwiwg5y6i,cc z1g hwfch+a (,g 5rse at constant speed at an amusement park. At the location shown, which direction b1ygih, ,wcag+5c6g r 5w( zhcfest represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path at consx m;+.wkvsa z067 burttant 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 circle from rs;uv6zm .a +w xt0b7kPoint P.
What is the direction of the average velocity during this time interval?

  08.15: A particle cont 1j)9cqlx 2z(dor/ d6bwd.q pginuously moves 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 thcl.1jqxdg)2 6 wodq/ b 9(dpzre circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwis*v-9rahvzs jxih )dwhxl*;1 , e with constant speed around the vertical circle shown. Which arrow best indicates the direction of the objh*1ilxj* w -r,h; as)h zx9dvvect’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mascu zfz,gq7 /3is connected 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 thefzu,/ iq3 c7zg 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 string?

  15.23: A car moves with constant spdj c8 p-2fufc)eed around a horseshoe-shaped path as shown with the arrows in the ccfdju -p)28 ffigure. Which one of the following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment witr1*dbedwcpx1i8qp) v+ :n 1a nh a simple pendulum that is released from the horizontal position at rest. At the moment showcaq1+8) pw n1v1i* r beddxp:nn 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) poinp ce+ntz 7d++ g :r-(a-qnuiunt-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 tu- -idq et(npan n+u+u+c:g7zrrntable 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 necess4beu:;.;b p 31; q)tefnkfyrh .rzb gxary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a sp4 rfethque r 1bf).xkbz; p;3;b.yg :need of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (masspee,e d k4a8tp(r6vl: = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times a secone: , ekapl(pvrt6ed4 8d?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m with fnj1w *c; .a9ni-xfux7 s ck,za constant kinetic ener9kszn i ;7.cnjf xx-w1uac,f *gy of 128J. What is the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball ijk;m97lg d+ wqs attached to a 0.80 m string and whirled in a horizontal circle at a constant sg d7j9mq l;k+wpeed 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 motion62d3rar wlm:l l7 vbt7. Which of the following statements is NOTw b2l7:lar3 7lm6trvd true?

  00.19: An astronaut in an orbiting space craft+)k2cz spgl 4qjp*j9h attaches a mass m to a string and whirls it around in uniform circular motion. The radius of the circle is r, the s9*g sj+p plqz k2jhc4)peed 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 u/nxtas 8d,;b mntil the string of length L to which it is attached makes a 90- degree an at; sbd8/nx,mgle 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 traveling on a rmv*oln+ brf7jxmrc-f3 5 h4 *uoad in hilly terrain, see figure to the right. Assume the car has nmxb* 74c jrff lo+h3*-mvr5 uspeed v and 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 speed of 12.0 m/s. At th5dy 2no mv9;q;vjv wdr :pknj030hcd.e 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 represe;m0k;yjnj dhw pv3crvo2d9qv 5.:d n0nts 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 uh+idgq/4u) fyo8 j;dconstant speed. The magnitude of the net force+ ;f qohu84 gdui)j/yd on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from r +v9f7gj5is 1fxc iij0est from the horizontal position shown. In the absence of air resistance and friction, the mass swf+9gcii70jxv5 1 fjsiings 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 pendulum. The mak y4mp9 :kq uf-bs*e,bss 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 acting on the mass (, kqm: -byksp9* ub4efF) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopper movouirz8d f.+n,fh, y,i0(zu vking at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, ,.fud0y+ , ,kunvh 8 (iorfizzwhat happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless s3ower 8 hr3gt2rdy5y4urface, 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 c2or ry43 3 r58etgwhdym 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 mha,oz-s htwe7ndg7 4+ass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force actid hoz-h+7se 7g ,4twnang on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coi:y:u nobo+ b(xns (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axi(+ b o:yoxbn:us 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 x)i4 chn 7emple2zi0k478y a4xz* dzgthe end of string and moves about the string’s fixed end in a conical myx4ehpz 7e 207 *i x gnz48ld)4cmkaziotion 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 uniform circular motion as shown in them hr+w mru0:y bt1dvy8ji.+ n ml639yz figure. The string to which the mass is attached has a length of L = 3.00 m and forms an an6r iv8 9zmj u3bh0m+nd yy1:+ymtlw.rgle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mafp --.o0:uj3 f+vkiwxp ek.kkss 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 angular acceleration ofok.- k.w u:pkevfp-kf ijx3+0 $4.50 rad/s^{2}$ . 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 kgfa)okv-5pha4f 8w1x wst3ib+ is attached a distance R =1.75 m from the fixed center of a disk as shown in thb 4apawh3fx1io 8-+ svt5) kfwe 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, starthd)3 55se jvd 3arjmw- oh:d2xing at the top, with initial speed 17.0 m/s. The object’sad)do5s53m -hvx:r 3jd h2 wje speed 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 inihqev b1kyxx xr6v* 89v*(9lgqtial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise throukqv*br*vq9916vxh (x yex lg8gh 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 sz-ma99 wvf9q bottom of a bucket. The 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 for the block to remain in place in the bucket. When the bucket iqf am9v9-s w9zs 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.