95.02: An object shown go8r +5c dkfy8in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force akdyoc8 8g f5+rcting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotatviwt:87 q6 tgfes counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by the seat and belt?vw8itf6qt:7 g

  08.14: A particle continuously moves in a circular path at consbt0 5z9ha6u vptant speed in a counter- clockwise direction. Consider a time interval during whzbv509 ta6uph ich 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 in7d+2 rbpfu+*8qx kibg a circular path at constant speed in a counter- clockwise direction. Consider a time in+ r28*i ugpbdxq +7bfkterval 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 wita 6*4ws3 tnrfk0q*u+ghz i)nh)z1narh constant speed around the vertical circle shown. Which arrow b1)h azg*n h kn4t)06zr iw3r+fqs *unaest indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to thel/c tu* tg(2nm0b +u.ur* w1.eto yjgb end of a string counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path view/bt+gujto* m t yb* 01w(rn..gucl ue2ed 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 -bg0r5t1 wdhc +;yllfspeed 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 average 0l5wrtgl;cy b h 1f-+dacceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment wukynrk(8g/e(i(q)sk5f ho,t c ffs-b *ym56l ith a simple pendulum that is released from the horizontal positmf5f s(yku/, r( tl*c8gybqkn65)k-s hefio (ion 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 tdb;m-l t,bzgg ,ey-z1he center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5.0 seconds. The coefficient of kiz,g1dby l b;t gem,-z-netic 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 force is necessary to keep a 1. 0 kg puck moving in a circle5qv ec f3r5nmc4k+hq9 of radius 0.5 m on a horizontal frictionlnq4chc mf59q5v3e+r kess surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration o6uah, :xh /ott q lq:flu62g1u.o/fkmf an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate o 616llothm2q uh/a:u/ot,uf:gf .xkq f 4 times a second?

  09.24: A point mass moves along a horizontal circulk8dly -:gl ,smar path of radius 0.8m with a constant kinetic energy of 128J. What is s ll8d,k: gym-the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached top50:g r h4qagj4 f4 b.gvxxaori 59ba7 a 0.80 m string 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 ballgxiagqbaoja5grp44.bh90 :f7v 4 5r x during each revolution is:

  99.22: A child whirls j70fw t517motc5pw gaswn87j a ball at the end of a rope, in a uniform circular motion. Which of the followo 5amwfpnwj 170 775tcsg8jw ting statements is NOT true?

  00.19: An astronaut in an orbiting space cr e rbds9f .e9c;qf7 .a6znune:aft attaches a mass m to a string and whirls it around in uniform circular motion. Tzs6e..fdcnq9 b9u; :r7afn eehe 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 untiw3 oj8,sz dqw3l the string of length L to which it is attached makes a 90- degree angle with the vertical. The maww jdq83os,3zss 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 nx4xfrgk if7 fei2q 0g4296xi on a road in hilly terrain, see figure 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 the car is most likely to gk7 xfi644n09iegx2ffr2 q xifeel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12i9rmso o(u8 78o bk l 22nqnab4vq(u.c.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 followb 2uiqo( ucam98 nv7 bkl4osro(2qn8.ing 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 mhx1m nux)yzo/1 +t7r cagnu xrn17)cy1o /hzmx+titude of the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M releaab hzb z:-:f/ased from rest from the horizontal position shown. In the absence of air resistance and friction, the mass swings through the arc of a circle. Leaa:b/z:h- z fbt 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 string formeyx s3 -ob, ,*sw1yv ehmgf58ts a simple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude of5etb m sy h1-w,3 fv,gsy*e8xo 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 fob 5vmpyzy76 :lrce of 5.0 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 the speed v, and the frequency f, of themlb yy: 56vp7z stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to an idsdmabz. 95 bta9 8x m;65ydq1 hgl1iwqeal 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 to 19b.wi5sa 81 q6m ayl5qd xhzg t;bdm9equilibrium 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 k wn8aghqt2z8lbv,ma):n8 *e 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 at the lowest point of the circle?ah, )8w8 l:kt2b*g eqan8zvmn

  14.23:Two small identical coins (labeled X andY) are at restonh *; kj2c8kox2w *w d0gq-bsrq8xbm 6s a horizontal disk rotating at a constant 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 bywsmgq kjcb20qsd *k*x-br62 h 8wo;x8 $d_x=\frac{1}{2}d_x$. 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 about9.q(u2 x3m:+k lu8b seilobdh 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 forms an anu+8s 9omx:3ui k2b hb(ellqd .gle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular motior+o5kuv d b.3f*6d ftqn as shown in the figure. The strin+t ukdd3fb * 6r.vfqo5g 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 30.0 cm fiz dk-f:pgv+ldsm0xh /e40/a rom a horizontal disk’s center. The disk starts to rotatpa:f 0gim0+x/hd -l4ves d/ zke from rest 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 distance R =1.75 l;i prpreisb(q:t(lb8 -,d+sto1 b 9om from the fixed center of a disk as shown in the figure. The disk starts (o( el9to;ls ,:1bspb-pr r+i 8tqibd 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 top7zi gy8hf:b(h , with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an anglfb hi7:hyg8 z(e 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, startimw)w/ir 7w d-png at the top, with initial speed 17.0 m/s. The object’s speed increases unifor di -)rmwww/p7mly 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 the bottom7vuyx 4u.6q a j2,gspbn 7z4jm of a bucket. The bucket is spun in a vertical circle of radius L by a rope. When the bucket reaga4y76jx2j vmsn .p4uzbu, q7ches 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.