95.02: An object shown in the accompvnkw(lz.fx* u8 ( 1ikbanying figure moves in uniform circular motion. Which arrowu .v1*bkw flixnz(8( k best depicts the net force acting on the object at the instant shown?

  05.31: A child is belteot5py1y-sja+c15qm(ikdvq. d into a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best re(t y1jasmv5 od5-iqky.+ c q1ppresents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular patidgs ;16 p2lssd3kcm- h 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 exactly half-way around the circle from Po1 3psc-sld s2d;kg6mi int P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular pathjn-ve 6 *rqvn- at constant speed in a counter- clockwise direction. Consider a time interval du-jv6n-*re nvq ring 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 constg85yds hh2j(xhkc z zo:9+6n rant speed around the vertical circle shown. Which arrow best indicates5zncjk hs86(+ hgyz 9ho:2 drx 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 counfx *x uxgxs1(e-f):xlterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the twirling maxx1x*x): s gfflu(-x ess. 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 asgme(9:j2 nw )/h.xo ld6qznl e shown with the arrows in th6 nwn(/l.mjezol ehgq)9 d:x2e 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 the Moon perform an experiment w*0xcba06woyzf l(- nu ith a simple pendulum that is released from thel0f0x cu(o6wzbn-ya* 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 objectbtb0s8flfa f3h, da32q c0z.u 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 is 0.50, while the coefficient of static friction is 0.80. What is thsb8lt.z,b 2a 3 0f 3ffuhcq0dae magnitude of the force of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 098j qrm7m/apr kg puck moving in a circle of 8r/ar9pmj7 mq radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acec v2oxl/; .-oxko3diceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at ;ekdxvlo-io2/ .co3x a constant rate of 4 times a second?

  09.24: A point mass movesxcv-f2 ep8+ty along a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of8ecy 2xv+-f pt the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m hlr/ ,hs)p)zostring and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the bal )hh/ ),rszopll during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular motioo6u6uu y;zf1 g( e h6(2igmndwn. Which of the following statements is NOT tgge oz1;un y66ih uwm u((6d2frue?

  00.19: An astronaut in an orbiting space craft attaches a mass m to zykq+y)z(l2 g a string and whirls it around in uniform circular motion. The radius2lgky)+z (y zq 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 gd3rlc1et s+..ghn8 vthe string of length L to which it is attached makes a 90- degree angle with the verticadtv hg1g8+ecnr ..sl3l. 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 terra i ( s+5qdzvhoz86k6brnd 2-akin, see figure to the right. Assume the car has spekqvkh+ z5n 8bzoadir2 d 6s-6(ed v and the tops and 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 constant speed of 12.0 m/s. A2 x/wv ,wut: dxfe27jdp-enm3 t the very top of the hill, the shape of the road can be approximated as a circle with radius 25 m, as indicated in e3n-pu: j7dx/wd,t efwvm22x 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(+yr 3gdz8 h*2prq hqq vertical circle at constant speed. The magnitude of the net force on t q q qhrh2zr+*(gp8d3yhe sphere

  11.47: A simple pendulum of length Lhasa point mass slp0o5( vm21 ha fmeu-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 neeu 1s(m5fval0h om2p- t 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 connected402 l6 is:uhgrkc4hse to a string forms a simple pendulum. The mass is released from rest and ihu 0gr 64hklec24s :sundergoes 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 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 rubber sg8bghlfbiqr *ruenp-**nx f02 x4- f.topper 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 the fre4 * lb phne*-xxgbrfq2.*fg0i nr8-u fquency f, of the stopper?

  05.28: A mass, M, is at rest on a fric+6 9lltu/xs qytionless 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 suy6tll 9 xsq+/pring 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 k t0u+ imfxg-,ty; v;nmass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is,umyg+tn t ;-fix kv;0 at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizontal disskw*,wexkh 3 koa38h ;k rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of the coins fr w*kh,3xk;3skw a e8ohom 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 ,zi z2ovw/(gwto 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. The string has a length of 2.50 m and forms2,(z ow igvw/z 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 shown in the figure.2 y+f 7 igh)0g skm2rk:jkuqapg;*w;q The string to which the ;h:uf; ywk7pr)igk*0q kqg2 s+ga2jm 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 ,c3e 2e1 eatet30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its cente 1eta3t ,e2ecer 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 distance R 24+7dmfr qnin=1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constant angular a2if4+d7 mr qnncceleration $α =5.00 rad/s^{2}$ 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, std ht,wppi7r iio4o7;-arting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved countercldi-7i7op,owr 4;pih t ockwise 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 initial speed 1uj,z2 8 fxgs1d7.0 m/g us8,xd1zfj2 s. The object’s speed 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 time for this motion?

  17.38: A small 2.0 kg block rests at .tz es+hi-tdg*83 sl)4ssmxy k4r/n mthe bottom of a bucket. The bucket is spun in a vertical circle of radius L by a reg m8rlsh+s/ s4.3nt-mk *t i d4szx)yope. 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.