95.02: An object shown /66lyvr14 u3ct3fligkm n -tzin the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object r u1m -y 6itv3kl4tgnzf6c 3l/at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwisam)r4*ql n9e be at constant speed at an amusement parkna*e9 )l4qbr m. 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 circular j;yksyt,pygtg o;vnxs6dz+ v8j7 -(.path at constant speed in a counter- clockwise direction. Consider a time interval d d.y-;+sxn6g z8(ovjk y;,s7t t gvpjyuring 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 , xdovawrmr1c7zibq9k e/8+ 5in a circular path 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 Q. Point Q is bdwe ziv,89k 7ram15r xq+co/ 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 cons7oy0aysm k9.dwsj 04ptant speed around the vertical circle showy4dpajsk 9m70ow 0 sy.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 of a string e;lyy)) tzs b/j k0z5rcounterclockwise 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 5trzl yb z0)y)s/;ejkfigure, at which lettered point on the path should she let go of the string?

  15.23: A car moves wi4h.d-ss 4rbb: vgj w1ij7,fixth constant speed around a horseshoe-shaped path as shown with the arrows in the figure. Which one vi4fbs s4ghjxj.7 wid b:,r-1 of the following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform ano8p) nxgd+)y slamw;6 experiment with a simple pendulum that is released from tdwm8n g )y;osp )+a6lxhe 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 the center on+um;zgq t8 zhhz(f,f4wx*aef: ,p1 p f a rough turntable as the turntable rotates. The period of the turntable's rotation is (zaeh;zpq1gxhw8pu4,,n* +z:ff tmf 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 forcku b+z4:t2d3ozwgj h1e is necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fritkz+b1j2hd4w:3 gzu octionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acc - 2v z2thrcj ly)ki8vo ..f;bu0y1niveleration of an object (mass = 50 g) on the end of an 80-cm string rotatingy0 r2- vbflz.8nku yv hi;v.j c21oti) at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal r(ifvai;l/ sp. whfhnj ;-bqwe525u jj2/6xh circular path of radius 0.8m with a constant kinetic energy of 12.h;x;/ hifl hjf52wu2 v( 5pbq- 6en/sjjraw i8J. 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 st5oy.sxh0yu7d ;s07gh6bzw f vring and whirled in a horizontal circle at a constant sdof5vbys7 x06h;7 g0 us. hyzwpeed of 6.0 m/s. See figure to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at22m/bf*jb -xxcj riwatc(o /) the end of a rope, in a uniform circular motion. Which of the following statements isi *w cfc/x)x2mbjj-bat (2 /or NOT true?

  00.19: An astronaut in an orbiting spac;q+i x5g8qr rd 4qb7;mswqe, ne craft attaches a mass m to a string and whirls it around in uniform circular motion. The radiu4qemsb;,rq iq7x w r;dnq58g+ s 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 o c bariul7dpx4 h5 qb*zp6 *:1a.m1occf 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 tension in the string when the mass swings through the ba7qcpop 16dubac*i.5*4r c h1 :bm xzlottom ofthe arc?

  94.15: A car is traveling on aliraca:r 7* 1j road in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottl: cr air1j7a*oms 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+u cpe inhi.89 tr m,z0)6exqb moves over a hill at a constant 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. Which one of the following choices best represents the magnitude of the up6ni.x9muqb+0,) t p z8c hiereward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at constant sp); cm9fs5z9dwt 8xhmfeed. The magnitude of the net force on the s mwhszd )9txc ;m8f5f9phere

  11.47: A simple pendulum of length Lhasa point mv(7*e; g hjjlqs)d p,kh5z8 aoass 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 gravitajhedl7s zgkp*oav()q j5,;8h tional 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 pendulum. Thp0xb5z ; fa9f9wmz (vie mass is released from rest and undergoes sima 9wbizv9z5( xpfm ;f0ple 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 on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of kdfy7u 41,dei+mc3e0*,xj) xo f c nqu5.0 newtons is applied to a 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 t xced,1 fuku+ jc7y nd)eo4iq,*30xfmhe speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to an fbyw.o53 sx5i ideal horizontal spring that i5y wfi.bo53x ss 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 by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a cx*pky1gav emlun/ ,- de)y5 r+onstant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. 1v yerp+n m gad-ex/)5,*u kylWhat 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 dispvwe -g++6mcxk rotating at a constaep-+cw6v g m+xnt 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 l,tel;m,2eeqpzy* u6 7m-odyis connected to the end of string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. Thepeq7zut *y; -y2le6lo,, mde m 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 circularjxs k; c; drfk t0h1,phk9e0(g motion as shown in the figure. The sttpr (g9 ; 1s0kkhdcj0, fe;hxkring to which 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 30g6ol 57ltv b8fi m,uf-.0 cm from a horizontal disk’s center. The disk starts to rotate from rest b58lt-,guli6v7fmfo 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 dis9j,8che8fpeb c zr)7mtance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constant anguph 7)z cb9rcj mf8,ee8lar 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, starc o7xgk4z9 :oh2 sua0cting at the top, with initial speed 17.0 m/s. The object’s speo cs u7x9k240:cozhgaed 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 at the top, wit ;cf-x02hbrdjh i 85pnt); 5kizw6noth initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an ang552xf;hni68-chkw0 tznj d p)orb ;tile 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 bucknvu ae 9 0((atbbuw/-get. The bucket is spun in a vertical circle of rat0wu a enu(-v 9a(b/gbdius L by a rope. When 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.