95.02: An object shown in th76d:j82 uwiv rse4 ante accompanying figure moves in uniform circular motion. Whic827 uwdv6:4a tjsr neih 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 counterclo 0rplu cvw37m)z 4y5hzckwise at constant speed at an avzmw0 uh c)74r5yzp3 lmusement park. 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 path at constant speed i ua5w1v mnam0-n 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-wama v0a-5 mnu1wy around the circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continu6btb; * /3sowzn n;i.wohf*n8moy 49 e;ydqkuously moves in 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. ;h*d;8f w/y wytnuske4b; zoqnb3i 69 o.*onm 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 withwyhfj(ab)o ,/4.8l k:vzz dql mdz o;4 constant speed around the vertical circle shown. Which arrow besq4doh4yawo.,l z bfj8:zl/v; )m (zkdt indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a smal- fkm r u..gl*kktcq+2l 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 letterk. *qltk2 -k r.ufc+gmed point on the path should she let go of the string?

  15.23: A car moves with consjc2x8zm7* nxm,j.u 4 kgri lc*tant speed around a horseshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the averagezxc 2.*7gul r4*8mcmjn i,xjk acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a si dxn2 m9ve jf9xu5i0r/mple pendulum that is re 9fmj5/vr0xd9nixu 2 eleased 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 re9 m )dj-kgycm3vdbz g8w+y3e2 sts 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 sved -k3)g wm 2jd+93 my8zygbctatic 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 13 /syl lszx*.6h6x n j9nk lbj7e;kec y0p70lg. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fric. /l l0 n;kpx76neysg3 h09y jcsxk l*ejzb67ltionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal accelerat2+yll76 lgmn mion of an object (mass = 50 g) on the end of an 80-cm string rotatiny l7m2ml6+gnl g at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m wim4 l kzf/ln;p/th a constant kinetic energflkp/ / n4mlz;y 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 attached to a 0.80 m string and whirled in a horizontx3gz :wl0 2zkjal circle2jzgkz03 :xlw at a constant speed 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 bal8mhb lr,z.o;l l at the end of a rope, in a uniform circular motion. Which of the following statements is NOT trum z8o.hbl,r; le?

  00.19: An astronaut in an orbiting space craft attaches a mass mk8ut,96 q g .s f 5xuyepauf(/v-hiw:q 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 t :5 q -u6a fyx fisqg.8vu,he9pkt/(wuhe 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 of length L to which it is ;8fz+ krb aad9f:u.cdattached makes a 90- degree angle with the vertical. T a+zdk u;.9cfdbrf:a 8he 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 trave-pz zn 9fbam*/ling on a road in hilly terrain, see figure to the right. Assume the car has na/m 9-zz* fpbspeed 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. At the vvt sog./7 g8p owc,zd6ery top of the hill, the shape of the road can be approximated as a circle with radius 28s6g7 .t,d ovgoc/pwz5 m, as indicated 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. The magz p1 1ilqdamx7+-1h gnnitude of the nea n+11hizxqd7 p1ml g-t force on the sphere

  11.47: A simple pendulum of lengtha izraw38v,5b Lhasa point 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 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 5ar, 8v iz3bawmass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simple pendulu3mht m7*t+ zklwro (7dm. 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 on the mass (F) when the mass sw37m+ zd 7twhrml*o(tkings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber ()njku wz03cc8eiu d* 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 the speed v, and the frequency f, ( n380j)iwck uec z*udof the stopper?

  05.28: A mass, M, is at rest on a fricti) eyyi/rbm 5x:onless surface, connected to an ideal horizontal spring that is upstretched. Aibr)e/ 5yymx: 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 constant speed of 3.24 m/s in a versv+iq6 ,fz+nvx* n5wntically-orient++xfi5znqw*v6 vn ,sned 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 :ck9o2e bp,oj y8a dt5andY) are at reston a horizontal disk rotating at a constant rate o :ja 2teykd,o9b 85pcabout 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 is connected to the end of string and moves about t 81 0r.kgzgrzyg4 fue/he string’s fixed end in a conical motion with a ezr81 g.4ufr0kgy /gzconstant 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 motion as shown in the fbm 0-mhhm5h2higure. The string to which the mass is attached has a length of L = 3.00 m and forhmh2hb hm50m -ms an angle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mass 11.0gb;*q+ uwsy)sb is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constss)q+w; uybb*ant 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 =1.75pg(7h(vv/wa 7 sfnff5 m from the fixed center of a disk as shown in the figure.pfv/5as 7f 7h((wvg fn 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 speed 17 sh4z0nh ; );09ha yl4plhhqubw35pwd.0 wpps n; q wu4lb4h h)0;hh3zy0 dl9ah5 m/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 final speed of the object?

  16.40: An object moves in a circle, starting at the top, with initial speed 17d1bi1ufn w:o98b1e b b.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise tbf9 bob 1ui1d8newb 1:hrough 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 k3xk:y dr56k4c, nmszp g block rests at the bottom of a bucket. The bucket is spun in x5spy6 cd 3z4kr nmk,: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 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.