95.02: An object shown in the accompanying figure moves in uniform circicm5 *k8)4 hkp,mq lpuular motion. Which ,l *mpuh pkq8m4k5c i)arrow best depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates coun6g e a(txoo)/ec)cb5wterclockwise at constant speed at an amusement park. At the location shown, which direction best repbxoa (6o)5 /g)ecwcteresents the total force exerted on the child by the seat and belt?

  08.14: A particle conru f1quox /)xu -.pz-ftinuously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this p)uozux-ffr u/1q. -xcircular 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 path at constant specrejzfojb3 *x:uu8n w+g5b): ed 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 arou:u*zn8egjw) :b5c ro 3bxf+ujnd the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwisecwj c-pby 2kx009exwxmp6p4/ with constant speed around the vertical circle shown. Which arro x6jwcb-40kw ce/p mx09pp2x yw 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 of a string counterclocoh k )wj 97pca56wtm3fkwise in a horizontal circle above h3om p96)7fwaw tkc5jher 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 should she let go of the string?

  15.23: A car moves with constant speed around a horseshoe-shaped path as sndzi736 zt95+ ahq nmphown with the arrows in the figure. Which one of the following choices best describes the direction i3qz5 h7n+6mdpz9 antof the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendulum that ;gosjkd5(uky81+jnk is released from the horizontal position at rest. At 5k;dkk u1jgn(j oy8s+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 ognd.hx(9xnj(ds3qacnd ; 7-g, pnv1from 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 coefficn,3q(9xj7 g odhn1; adv(cgps n.x-ndient of static friction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force9i .p7hima6y 01 jbpqf is necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface wiqpf9 7a hmibpi1.6jy0th a speed of 2.0 m/s?

  05.03: What is the centrf.+ 4ag 5gor:gndt pf/ipetal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times a s4n+:fpodfgrg.ta g5 / econd?

  09.24: A point mass js o8j,a5d0xzh kuxyb/eq2gg)a3/ l 7moves along a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. W8k qj5a)72bd,szhy/ex0 / gjo x3algu hat 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 whirledz jic 5(s2wbire2 e:)s in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right.i ezjes r5w2() bsi2c: 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 un:i*l yonz9(uq7dw )wv iform circular motion. Which of the :*wdyizu w(v)n7l oq9 following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mas i:i4bbq7mv9. sc5kbsz6j d byw z71z5s m to a string and whirls it around 5z s5c747is:b qkbbdyz m i69j1vw.zbin 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 outward until th-6939 rm92gam nu7wr qhq;z zmuqlz)re string of length L to which it is attached makes a 90- degree angle with 9z 3z)qmrmn 97mquu29q rra g6lzhw;-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 ter6 em p em xk/r5)yyo;e2jfv)7lrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have rrkxy7)6/foy )2emj v5;mpleeadius 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:d 8d 05,wdjlytr o+8y+cg0rj:oe-k)nqdiej the very top of the hill, the shape of the road can be approximated as a circle with radius 25 m, as indy, e0-)o qli+r:jok+jn rjedddywc0:d5 8g8 ticated 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 speed. ,q s elxqeo5 6ug28j/pThe magnitude of tq/e6qpo,elj2 u58 sx ghe net force on the sphere

  11.47: A simple pendulum of length Lhasa point hkkp om 7/ yya a(g(vp:e.qe1*eu t9j)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 thee mep/1hkoag*:v (tup( q97k jaye. )y 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 px1o i9*w. tc75 zwkwtrendulum. 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 grax1woc5ktz *7it9rww. vitational 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 l 7r/qqf/k htrp5tx5jc41wq . rubber stopper moving at a constant speed in a horizon x jqkl.tqr/5h/ftrwp 1qc 754tal 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, connected to an idy1)6y-tf s*ggbdv w6c eal 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 ba*6fds6g1)by- ytvwc g ck 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 a constant speed of 3.2z*5p00lw evrqps 7 ;wr0q 8jal4 m/s in a vertically-orientedwq 8rre7jvlsl;*qa050 zp w0p 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 horizontal 7nui8 ew4xr /vdisk rotating at a constant rate about an axis perpendicular to thenuwexv 4i78/ r 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 end of string and movxbl4e39gkj9bci +hfpw,.akqyebn 0c:, h5 p 0es about the string’s fixed ebalp5:,0. 9cqc49n yi,+kwh kejxbegpbfh 30nd 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 ic0-kv w l i0kepvy3-r,n uniform circular motion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and forms an angle of 3r -eipylw 0 ckv,v0-k$θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mass 11.0g ijnr v 3 gpixcb1r.b;27s at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant anvjgbrb i 2x3cp.17n;r gular 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 bgkw*vl a4v gxod:;-xomrl: -c9*qb7 is attached a distance R =1.75 m from the*9 lgg;xx4bvc*-: oko drb-lv: qw7am fixed center of a disk as 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 the top, with initial speed9),t+i*i5ioc0krvrba*yc ophpc 77n 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise througk)apciopb* rhn70t vi*ccy 5+9i 7,roh 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 initiae j) hmmas u4v(,rgqw25/go3 zl speed 17.0 m/s. The object’s speed increases uniformly until it h)/5g24gauez3h,wjq o s (mrvmas 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. The bucket isvgefry )s/e 6+ spun in a vertical circle of radius L by a rope. When the bucket reaches the highest point in its motion, it moves just fa6rs / evey+g)fst 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.