95.02: An object shown in the accompanying figure moves in unfcqn8lpr)) q+iform circular motion. Which arrow best depicts the net force acting on the object at the instant showq) rf)pc8nlq+n?

  05.31: A child is belted int 33gii6j r z)waq+pfu/o a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement pa3fp+6izqwr 3/aug ) jirk. 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 moves in a cihca8kmc;n: k ie5vn/:rcular path at constant speed in a counter- clockwise direction. Consider a time interval during which the partickea5h :knc /nmc8;:v ile 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 circula ((t q hkfje fl14q*:cen.uoy+r path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular path fr 4 +*: ej(efcfq.(nuhl1kqtoy om 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 5 *(c mhzhc1oharound the vertical circle 51zccho (hh*m shown. Which arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a smallt3vh:po pyqt0sh7o(w d764o w mass 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 the girl needs the mass to pass through the point labeled P in the figure, at which lettered point on the path shoy3 o h6ww 0q7(od4ptv:sthp7ould she let go of the string?

  15.23: A car moves wityi z 7,qb:9l/:xsx j2j sor2zth constant speed around a horseshoe-shaped path as shown with the arrows i:7qixjs yltz:2 j,zsbo29rx/ n the figure. 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 tfxb qr db/zdru0d d 458)4n2vzhe Moon perform an experiment with a simple pendulum that is released from ther44n/0 zdd5x8db )urfz2bvd q 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 obje/:pd+ na vglr)ct 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 turntable id+ngl ) :pa/rvs 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 necessadd+ezi8 vlp5pd)ix0wx) 88 qcry to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fri)i 8pdxc)wdv die lx8zp+0 5q8ctionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an os vlgw, se33xwn/9sc9pm.t -pbject (mass = 50 g) on the end of an 80-cm string rotating at c.l9-3ps3xv t e,s gnp/ws9mw a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path oq,jw f)xxs,r7f radius 0.8m with a constant kinetic, ,w7qrxjs )fx energy 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 attachej *r6khd cr 6ur42maz4d to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/ r6krj2rza64mhu d *c4s. 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 ofy mn1x dj22x.qo)y; xs a rope, in a uniform circular motion. Which of the follod xxo2y1 smy .)xnj;2qwing statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a string an)a rpns5,u 0a59lnklhd whirls it around 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 top5lun0l5 s,9rak )nah double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the st,vc .tp jaz*c7o0,aatring of length L to which it is attat7azv0.a*c,c, pjot ached 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 ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the lvw m-;y,: d rmk+zi7d6ogru -right. Assume the car has speed v and the tops ;- mrlw:yd+,k-u rzmv do67igand 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 consta6;qymyuc sp2k3.i1za nt 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. Which3 yq ksa2u1 pmi6yz.c; 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 ve54a4+ fu, msws uoemf,rtical circle at constant speed. The magnit4m, uo+f wa45,em sfusude of the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mas(f9)4tk/iew oh5-fh z r.be ryz pj3h;s 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 -oh(yzebre/f f j5;i3 hw) hr4.k9ptzF 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 aydw 7q++ ofy+q 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 magniwd+f 7qo+ yq+ytude of the tension in the string (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 applied to a rubz)ip 6ttn(/otber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but ttoz)p(int 6t/ he radius is made smaller, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is atiikn,rvq11do f6; t3a 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 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 byd;q1iaon3 r, kf1 t6iv the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constan6pdjf 3l- -5pnsw*g ngt speed of 3.24 m/s in a vertic-jd6sl w pf ngp53n-*gally-oriented 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 (labeled X andY) are at reston a hms :2tm;iqy p.orizontal disk rotating 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 centermisp;m2:.y tq 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 sti rg :dszmc,l+u bzutv073 49kring and moves about the string’s fixed end in a conical motion with a constant speed of 4.0+u0is3rvz :7b9lutm4 z, ckdg 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 ssn7m ssycs*ilgl z8o 1a +mgb(h m6g8k (3el96hown in the figure. The string to which the mass is a8cl zglhi +6sg a*g87esmk msm1(lb3o6 n9(syttached 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 masof9*k,)u yx 2elrpe7 is 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 ofxkye)p eio 7 2,*lr9uf $4.50 rad/s^{2}$ . 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 mfoswe(6q *71g*v yr9q( ty nflass M = 2.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the q9rt s7y*1 e6g l(y( o*fqwfnvfigure. 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 the top, with initia -t js9qer,vc2l speed 17.0 m/s. The object’s speed increases uniformly until it hacjvt sr-,9eq2s 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 cii r244 )ucwc(mlrikw.-0q z11qaulq 6umsc-prcle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniforck44m.6c01qw1 (ulpu i z-2slurir)-c q awmq mly 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 bottoang./ : 9qci pk7mlgxfn-e;c y(*m; rcm of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucket reac q/ ngxc;;-.:ce9n fg(p ayrl m7ik*mches 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.