95.02: An object shown in the accompan3ym4e ; teczz)ying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the o tm3ez)e4z c;ybject at the instant shown?

  05.31: A child is belted into a Ferris Wheel seaq)j waztz32x r5q23ho t that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted z qj25w3)h32arqztoxon the child by the seat and belt?

  08.14: A particle continuously moves in a cir h wafx+ro2j1g6y9 d)ccular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle mo+f2 )hxjg 6c91wdro yaves 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 mzy4a/fl;min47 np b- ioves in a circular path at constant speed in a m4 yibpain7lnz 4;f -/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 Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant speed aroup8c9us cy(x7r)b4yv n nd the vertical circle shown. Which arrow best indicat8ry 4(bcv xcpn97y) uses 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 of a string 2t,r ky898agdy ns1jna)a pv;counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the twin9)nvs,d; ygkap1aaj82tr8 yrling 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 path as shp0 o. ugfw.8rsown with the arrows in the figure. Which one of the following choices best dosf.wp.8g r 0uescribes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an exujxf 4zhi.b;:periment with a simple pendulum that is relxzfh i 4b:uj.;eased 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 fry.u9:t yglu r44gsg. vom 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 coe4 9r.ugsl. 4vtg:yyug fficient 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 keep a 1. 0 kg puck moving; .rb ,7nq ik8,kdd 9pnc 7rdoahh/lx6 in a circle of radius 0.5 m on a horizontal frictionless surface with a speedr9 dddk7 l ,x/qrbpi;8k6,ha. onc n7h of 2.0 m/s?

  05.03: What is the centripetal acceleration m 0-af -sxlf4z57xq .o1mq visof an object (mass = 50 g) on the end of an 80-cm string rotating at a constant r x q47ls. -i -z1qmofmav50xsfate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radiusvap:r*2lj9x g 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force 2r*l9: vapgj xacting on the mass as it moves?

  96.24: A 2.0-kg ball is attached tozmin 4/.-jj et gt.o+d a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/si +jm dz4tj.- egn.t/o. See figure to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a - uw2ojdbm9a1 ball at the end of a rope, in a uniform circular motion. Which of the following state1uj -a om9b2dwments is NOT true?

  00.19: An astronaut in an orbit /96odokq 7mm 9fioku, cu7i0kus9- xcing space craft attaches a mass m to a string and 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 to double the tension required to maintain uniform cik9o 06 mu9dkum ki-i/s ,97qxouocf7crcular motion would be

  07.22: A mass m is pulled outward unt uvb,w+;8*.2qhrzg hjw zp +txil the string of length L to which it 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 t+* ,j+prwuw.x vz8;g btzhh 2qension 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 g00k0 xstepg7figure 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 th7 sx e0kpg0gt0e 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. At1fx*6ofdm0m m 0dcizasrw*2: 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 represents the ifd*x0w osamz0c1m:6m d2rf *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 spe 6wshd47f8nlg:3 hvvn ed. The magnitude of the net wh3hgn4 d8 sv: 67lfvnforce on the sphere

  11.47: A simple pendulum of lengvdq3kqgw,cb q v8-97.0 a awkjth Lhasa point mass M released from rest from the horizontal position shown. In the absekb9vavjag7qq- .,3 wc qwk80dnce 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 the bottom of the arc (point P)?

  16.32: A mass connected to a strir d k6xynd5:yold2w+qe 6nc*9ng 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 force acting odneocq2 dx9wy n 6dl*ry+5k:6n the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to j4wx 1 a5v*bvva rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smal bj1a*w5 vvx4vler, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless sj701 wh sd4- ytdsjx,purface, 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 ,d -01hj4tswdps xjy7 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 aq )h9/-5hr .c mjwttsu constant speed of 3.24 m/s in a vertically5hw-)u9jt hrt /q c.ms-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 identi iyhy8c3 .*::bymvd jccal coins (labeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the pmyy:jy v* dhi3.c8:cb lane 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 about/,az d6ett b3f/kc6kx the string’s fetbxdk63k t cz6,a//fixed end in a conical motion 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 motiv k08lf03qgc eon as shown in the figure. The string to w 8q3 klvg00fechich the 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 11.0g is at rest 30.0 cm from4;owj 1jsnzdp97 m g0b a horizontal disk’s center. The disk starts to rotate from rest about its cente7djnw4opmjb0;g 1 s 9zr 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 0gio,n; a6vqo3xrl6a = 2.0 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 fx o6r,n3; 0giva6l aqorom 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, w/zu+ng cbxi*ndnyp- 0 a*+rs7ith initial speed 17.0 m/s. The object’s speed increases uniformly untind7sbnz+r-g+ca 0*i nxu*py/ l 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 .qks bl0vj6y7 ) 4wfllzyb:6c initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise throu.b c)j: yyqk7wlb4s0flz6l6v gh 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. The bucket is spun 7;o6 b+fal kem2drtd. 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 rbtr;d 2m+ .6laef7 dkoemain 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.