95.02: An object shown in the accompanying figure moves in c5uv;ny .wi a m5g2nkv cb83f.uniform circular motion. Which arrow best depicts the; v8n.2i5 buvfn5wk ym.g3acc net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwise ((9eo ck v7xmggkj (y-at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on thyxg7g ((jo (-v kkmec9e child by the seat and belt?

  08.14: A particle continuously moves in a circular path at constant speed in y4yx i 3sla5,ya counter- clockwise direction. Consider a time interval during which the particle moves along this circular path from point P to point Q. 3i lyys54x ,ya 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 pathn(nfh,zo)b-(dugwky : 0d 3zugit t 77 at constant speed in a coun(gt d :,-u i7wfoukz3n)g0yt(h7 bznd ter- 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 Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant speed around the vertv4y. ln oa:j(tical circle shown.y:jt (aol4v n. 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 connected to the end -xwswwkp dwk- 9rvozh,0743ed.mv 8f of a string counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above tw8wd-of, w vw es-94d7k0xk3rp hzvm.he 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 string?

  15.23: A car moves with constant speed around a horseshoe-shaped cqxdbbm**;5-m e zq b6path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the car in traveling fro5xm b-qeb*qdc6 zb* m;m Wto X?

  08.35: Astronauts on the Moon p7+j:gsfjwx .o+lt7ok)9m pm uerform an experiment with a simple pendulum that is released from the horizontal position atk o7jolfmw.st gx9 pu:m7 j+)+ 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 fro 9ly *o1an4nl4/ robpz,rf2aa fbw1d5m 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 turntable is 0.50, while the coefficient of static f1ybl/a41p ,noda25z wrffr oal 49*bnriction 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 movi)knn 3w( waknem c+rm:m3a :)jng in a circle of radius 0.5 m on a horizontal frictionless surface with mm j )e(wr3an3+:nk:)cmnaw ka speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g) on the k8sb eeznmn8,azj 1;3end of an 80-cm strin,m8a sekn j3be n8zz;1g rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circ/+, q sdcchu(eular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on tqe/us c+,chd (he mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 d/caeht 2u6,pm string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. T6thc/p,ue a 2dhe work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in:z4dl+ayrr 1 5jvhy:7ku vth8m1m61ilmfp u1 a uniform circular motion. Whicuyjly pm1mhd+61z8l :1hvk7f m ua1rr t: vi54h of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a string an+ av5+xbbj + wqgzbsu7lb3((kd whirls it aro(v zq bxw++s5bb k b7(aj3g+ulund in uniform 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 outwx-c+qqkhxycg m -zpfe(/8)z6 ard until the string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is relea-6-py+e q f(x cxq/hkzgz8)m csed 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 f9 1afy 8c(, /nnmjzu tjrae71jigure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The driver of ta 7utnn 1j8(aj9zmecyj f/ ,r1he 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. 2rq b8)xuec5)lu 7qlgAt the very top of the hill, the shape of the road can be approximateuql5 qcu2e b l8rxg)7)d 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 circle at constant sesaa) zz;+d; speed. The magnitude of the net d;a +)s;ez zasforce on the sphere

  11.47: A simple pendulum e6ujr7vd:4sep8a 9c v of length Lhasa point mass M 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 folejuc v96s r:p7 4ed8valowing 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. Th j) 35iocccj*re 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 gravitatcjc o5 jirc3)*ional 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 a5f,1qfi9ajhuct 1 - mx(2 lqpv 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 tcih 2-u5fxa9m,1q lptqf1j v(he frequency f, of the stopper?

  05.28: A mass, M, is a2f llr0w3)y8udk1 yzr t rest on 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 equilibrywfu8) ry k03d21z llrium 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 3tb/**zam-m5glrm qeo 0(pj av/+ u;i a.24 m/s in a vertically-oriented circle-gml*/q;raie/jaum (t0+oam 5 vz* pb 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 upyns;-g,f 1 ndisk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of the coins g ;p1ysnn-u,f 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 about the st 8*bc )yd /kuthkclq3p9y-tp/ring’s fixed end in a conical motion with a constant speed k9/3l8t cqud) -pcb k*tph/yyof 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 circulvge ry7zc,-;lar motion as shown in the figure. The string to which the mass is attached has a lenc;,ev ylgr7-z gth 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 fr8wmu : *zqjuq)om a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angulq 8q)*mjzwuu: ar 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+ no w*jw5jzp1 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constant angular accelerati15*zjpnojw w +on $α =5.00 rad/s^{2}$ 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 the n+ x-r)7yn(wq m)t ievtop, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved countercr7x-yqti)(w+ mn)n ev lockwise 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 afkchmuqk3 v,( . lm .-.c;yduj circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it hasm fjl d-v, .cchkm(..u 3ukyq; 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 ke3z g.sn7fqpi qdb,4 ;g block rests at the bottom of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucke gndipbzq47q.f, ;3est 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.