95.02: An object shown in the accompanying figure moves in uniform cioi8ffy o-(qe(p/e a 3- bcjk4hrcular motion. Which arrow best depicts the ie hobejc-8kf (o(p-y3fq/a4net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that r xtrfrzz vi5:r:-j;ucc.)d w,otates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force cr 5,vfzd.xjtzur)r:w -;i :cexerted on the child by the seat and belt?

  08.14: A particle continuously x82du+gqde i -moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interg-uedixd+ q82val 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 Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular pq,ax xo /2s/xlst2,znoxs7)g1c r+ g eath 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 x1,xgxe)sqs/tz/2 2x nsgrol+7,ca o 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 a6nsbyu77 e9 vge4 ay8xround the vertical circle shown. Which arrow best indicates the dire8 vuxysg76en ye74 ab9ction 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 string coun z l0iy6k;it*tterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the twirling mass. Ifi0 ;ytli 6k*zt 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 string?

  15.23: A car moves with constant speed around a horseshoe-su pi6cp-iemjdk 8a(g-*r1jc: haped path as shown with the arrows in the figure. Which one of the following choices bej *18:apujepk icg-mi(rc 6 -dst describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple penxq0c j q5wvb-noc77 6cdulum that is releaqvoq bcjx7w056 cnc7- sed 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 t ) bgo/( yi yb/e+nh)(mqdcke8he center of a rough turntable as the turntable rotates. The period of the turntabl//+ k bne(ehg)cyb d(imqyo)8e'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 is the magnitude of the force of friction acting on the object?

  07.19: What net forc:tp,f; d3wp b b9-ngpre is necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface wi9fg n,-tp: pbb;rp3w dth a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 ghnldqw;7 7,eu ) on the end of an 80-cm string rotating at a constant rate of 4 times a secoewl qndh7u ;7,nd?

  09.24: A point mass moves along arbw)r5b )si0c horizontal circular path of radius 0.8m with a constant kinetic energy wrrs i0) c5bb)of 128J. What is the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and wh,36r i /mkc 2xlzwrw-jg4b5tairled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the ball during each w23/ ia w-xl,c6 bm5rkg t4zrjrevolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circu/ 0;9 )im; qyqvksqqht.ug5rzlar motion. Which of the following stat.5 z9 i yq)r qvg/hq;km0;qtsuements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a strid 1f30futn ku8ng and whirls it around in uniform ftu103k fud8n 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 required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of lec-xho0r: pj8 qngth L to which it is attached makes a 90- degree angle with the vertical. The mass is rj x8h:cpo r0q-eleased 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 road in hilly terrain, see figure to the r3kzv) xjqhm +ym;+o 4might. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The dqxmj 4hm)+omv;+ k zy3river of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0h7trx+;7 fbqk8 bz3ww m/s. At the vtzr 7f+7kbbw; w3 8qxhery 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 magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical i s3rgq9utew)4 //hskcircle at constant speed. The magnitude of the net force on the spth /3k4i)w qe9/srusg here

  11.47: A simple pendulum of length Lhasa point mass Mmu 0ydk ;wyt56 released 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 swings at thew0 md6;5tk yyu bottom of the arc (point P)?

  16.32: A mass connected to a stru ,d 9-ns(t7k5 ershxting 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 gravit,k hds9n7 x-r( u5ettsational 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 applied to a rubber stoh8802cytp9tmr/p ug7x,rz+o nq2cihpper moving at a cx2m/8 yhtc8p,cqn r rp0o+i7g92utzhonstant 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 frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, bs t0f8 l/wv0aue.y i8connected 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 cw 8/0la0vt. y8fsubeionnected 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 s msj(usu s+*y f7u3;qn4s: ukmass with a constant speed of 3.24 m/s in a vertically-oriented kqm* s u;fs7jn+s(:uu34uysscircle 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 (labeled X andY) are at reston a horizontal d,wdw8kv2r u h(isk rotatiwdh,vruw2 k(8ng at 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 exm*qtsf nosc)9td,4 ri9+n 1u hyx3 +;ih qk,znd of string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The sm 3h; ,uysfthx4o,qicd 1zri99+tq*) xk s+nntring 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 ;ja2i j)kki5iin the figure. The string to which th2aj;j)k5 kiiie 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 11.9eg3t2vcxq b.uv 7e:h0g is at rest 30.0 cm from a horizontal disk’s center. The disk ste97t 32hg:vuvqcexb. arts to 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 = 2.0 kg is attached a distance R =1.75 m from b *2zoa wzo+ gx6bq41tg7zq:dthe fixed center of a disk zo7wx6q* at4bo1g2dz +bq: zgas 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 in a circle, starting at tx2e ukcc6ka0sqo: b, +he top, with initial speed 17.0 m/s. The object’s speeua0q e:k6o 2bk+cscx,d 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 e/w9c-lpcbb*xui1 2zc4 t2hn at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has1b4 c *9xtz2hw lb-/inu2ccep 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. Thgwf ak*:lbwglvf;wzq8p a20-93fx ( qe bucket is spun in a vertical circle of radius L by a rope. Whza:2(wl8gffp3 aq;qk0x-l b*wfvwg9en 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.