95.02: An object shown in the accompany+ qf3,(a csf q6f3fbju(vdxm 0ing figure moves in uniform circular motion. Which arrow besj cmb63d3 q(,ufafvq+sfx0 f (t depicts the net force acting on the object at the instant shown?

  05.31: A child is belted intolxl5(g4 - ervu a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement eu-(4xgrl lv5 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 k2rh:oq0lgg)c-r;h * g1 nzkcn 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 Point r2 h 0klkcchqo n-g*gz:; 1)rgP.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant speed inj ejsxr-i;rfs*z 5m)d(d;p c7 a counter- clockwise dir id-f;pc7) s;ejzm(j*drxs 5rection. 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 Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant speed aroun48lbuwc*lq8lyk nti - :ahh6;d the vertical circle shown. Which arrow best indicates the directio-4kh uahi 6l wq:8nlbt;c8y l*n 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 co) b gcfhen75xvp .; z6rb3hu+bjpea57 unterclockwise 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 lettered point on the path should she let go of the string? egx p 5bh5rz.a6; puev3nc7hbb )j +7f

  15.23: A car moves with constant speed around a horseshoe-shaped paz/ano g:8xjwpxc1 3 fv+-h sxeo2a0q. th as shown with the arrows in the figure. Which one ofjfo1 x-2 apxqnxca+ :.3zewsg8v0ho/ 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 perforus.folqas srx amusa,+ 8*1 i 0,.ctgpmb)(7hm an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the diagram with.1oulhaa7x i.m,+pqc t)s ssasb8 ,f( rug*0m $0^{\circ} < \theta < 90^{\circ}$ , 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 of a rough q(,utiih;kok2(fpd ;*r 7nbe99oce l turntable as the turntable rotates. The period of to*72q ,9 k9(;hfcptn(udr;l oe ke iibhe 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 the magnitude of the force of friction acting on the object?

  07.19: What net force is necew/e9+7odu4k z 0rz 3krp k)f6fwo5ebm ssary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fro/ek3mwzo kf+krpf5rzw9 )7 bde4u6 0ictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acce f6*/ cb3 qqp+d3jx5ypwqshz1 /br3 dvleration of an object (mass = 50 g) on the end of an 80-cm strindpwyqdqx5hv3j z+cqf* 6 /3 pr 3/b1sbg rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular patjyjb (o wg e.+59tete)h of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as it moves? jbj)egtt5o9+w yee(.

  96.24: A 2.0-kg ball is attached to a 0.(n ls01k1umql 80 m string and whirled in a horizontal circle at a constant speed of 6.0 m0muq1 ksll n(1/s. See figure to the right. 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 uniform cir,hkvf-j g(t0 scular motion. Wh (vt0hg,-kjsf ich of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attahnar r(y; qay3 f,+ 7(e+f ypvaemah6.ches a mass m 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 the tension in the string is F. If the m6+ma.f7 (f,3e ep (hryq+nyha vaa;yrass, 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 trzc.u/7,pd xn he string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest a zxnu7 ,dpr./cnd 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 terrain, see zs8f cdl6) 9p:d6aevn figure to the right. Assume the car has spee8e a 96vfdn:cdlsp z6)d 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 mov.ouu3(hpy(o; tjh4 1e d2w scuhk)u.mmy* 0ykes 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 myuyetw)4(2;1 o.c yu*uh3hod.kkps m hj(m 0u, 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 aawc)jq:w (m 4yo786jylyr .e bi9woe3t constant speed. The magnitudeyw3 obcy ywe7jaei4(.q 6o8 w lm)jr9: of the net force on the sphere

  11.47: A simple pendulum of lenqsw) o n1qekz ok90wz:4q 7h:dgth 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 0q1oe z7o:ww :4znsdq khq)9kof 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. The massf qu; o96ycbn,m.wgcrnk/t .80(rw aj 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 masrcfcq( . r6,.nou09 /byw akjmtw8gn;s swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopper movz ty:sv-n)11rnozcg gc2; 4zoing at a consta ogzz1 yco-sgnz1)tc24nvr :;nt 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 the stopper?

  05.28: A mass, M, is at rest on a frictio8psd b 8o)-vursy0u3l nless 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 spring is brought back to equilibrium and the mass connected to dsr-yu88psol)3b0 uv 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 3.2(xh (kv7vo.a q4 m/s in a vertically-oriented circle of rk((a7.xo qv hvadius 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 horizonnq2dy d*6trkqzr 0dp;*16x uvm zy0w9tal disk rotating at a constant rate about an axis perpendiculazyd y2m x096r;6wpdt1r* *nqvz0kudq r 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 tb5:x7mjb:7 )x v(l nhjqq wj+po 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 forms an angle vxw)x:lmjb:jpb757j( qq+h n of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular motion )b4 9voyih4rdas shown in the figure. The string to dv44ir9 )hy bowhich 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 from a horza*k 0rmz dpx+50-zg hy/i 3uvizontal disk’s center. The disk starts to rox-zh0r*5 3+iyazd u pmv/zg0ktate 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*m-kars8xyuwg3 b4mv )6p8a j is attached a distance R =1.75 m from the fixed center mmr8gs8 jp6y wvb*a-) u3xa k4of 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 speedcd5 e7 /0dwdwp 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle dce dww/75dp0 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 speejecb-ccvo)-fs ,; 7ns4q j(xcd 17.0 m/s. The object’s speed increasesvc-o-bx,sf jn;qj)e7 (c ccs 4 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 the bottom of a bucket. The bucket is spun mi y *: ob,a*r b*h/lhcklwabpir2 t97l544e nin a vertical circle of radius L by a rope. When the bucket reaches the highes9b bcei:7b44l*l/a ryam,rholi tkh5*n*p 2w t 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.