95.02: An object shown in the accompanying figure moves in uniform circularp t; (.s2m4xt5ghuwlj motion. Which arrow best depicts the net force acting on the obje 2ug5 .ls;pj whx4(tmtct at the instant shown?

  05.31: A child is belted into a Ferr)-gg 1i2pk ol:ya67ptby4rp v+h rr9wis Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location show:pg67pl1h-riv ok +y9rrwb2ga )t4 ypn, 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 in ak1-v.8r6k gy pvnase+ counter- clockwise direction. Consider a time interval during which the partik-8gp1rkv a6vs yn+.e cle 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 cb1or. 3 vxl8ok:, 0+ndlhpinz ontinuously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval durixr.lh,bzoldn +p:vo31 i0k 8nng 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 around the vertical circflth0bh7oqc v3 x7k *n:45r kl3ptr.ule shown. Which arrow best indicates the direction vpl *5b nrt3ulh0ck tf7:q4k.7orx3 hof 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 countewp5yc 1:;on-fdcug/c+u-p p u rclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from above the tgc pp/ync do-c+ u1uf5u:-w;pwirling 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 speed around a horseshoe-shaped patztf j8izd) dr fyb*)6 mv15s+-gzc0nih as shown with the arrows in the figure. Which one of the 5y+-mindsfjbc1 )tzr)d 8ig z0zv f6* following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon performhw so2-qp o2j ty5.a07dy/ky2,i(x;ty wffs h an experiment with a simple pendulum that is released from the horizontal posws ,xkow (0sq2 a-yj5t ht;h27y dy/yi2f.fpoition 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 ote2 :saygeawug02d73la 7,bcbject 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 the magnitude of the f7cb7aug2,0e e atylad g:2ws3orce of friction acting on the object?

  07.19: What net forc 96g5rj1uqexle is necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a rq56g1lx9 j uespeed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 gczbw yb)* 2u(8u io*md) on the end of an 80-cm string rotating at a constant rat umyz) o2 d*i8bw(bu*ce of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m with y: yf v7c1wv b72ea,uha constant kinetic energy of 128J. What is the magnite,: bfh 7cyyu1av72wvude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.fy 5n (zs1o;ao80 m string and whirled in a horizontal circle at a constyo1noz(5 ;afs ant 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 ball at the end of a rope, in a uniform circular moti jesfko(d qnjyq gtl/9,- 8)s0on. Which of the following s( 80 j9ktlsqqsy,o-gd/ en j)ftatements is NOT true?

  00.19: An astronaut in an orbiting space craft attac7g+a71k j mapmhes 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 k+mg71 pmj7 aamass 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 of lenepyf / w4tx(2igth 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 bottom of tp2iwxfye4/(the arc?

  94.15: A car is travelhlk(vrt.:q7n ro t 23uing 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 l2htr3:or .7ku(nvqt car is most likely to feel weightless:

  17.10: A 2000 kg car me -xc(t kxf8ho5-8rp goves 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 upwardpoe-8kx 8(-hgtrfxc5 force exerted by the road on the car?

  97.13: A small sphere is 4vr-mtz+.rj y moving in a vertical circle at constant speed. The magnitude of the net jvr-+y mr4zt. force on the sphere

  11.47: A simple pendulum of length Lhasa crq:zoeo8ayu,k*0 kx6 k)3jfpoint 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 08)qzxy 6o:rj oc3 k*ekufa ,k 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 ydaiw8* 1t7 bua string forms a simple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correct 8 aduwbyt17i*ly 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 of0smm b4x* ju cb0o+ ktbn7*+bu 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 th *cbsbxm* b4ub+ om7j0k0+u tne stopper?

  05.28: A mass, M, is at rest on a frictionless surface, conwhw0nz-x (cueb8p 9m8nected 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 ane8m bu0cww p9 8hzn(x-d 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 3o;8c.u 1z.z gs m9.ewoesq8vt.24 m/s in a vertically-oriented circle of radc8 8os 1 vz .mu9soz.w;eet.qgius 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 reston0m1 h.3cxe ihd 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 dis0hi.xcmhde 13 k 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 an4r g0w 9,8d-khjwd; (m dklvttd moves about the string’s fixed en m8 ,v(ljgh w0krddtkt-d4w;9d 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 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 shownv.e 4g 6wss9esqc,)v e in the figure. The string to which the mass is attachee . v4g6ces9qvs)e,sw d 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 a ozv h440 pupu.2md.ist rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its ce opdizhu0 44pu.m 2v.snter 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 = 2kf/7s2ah o(b;- xengn.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constant angular/oe(f n;gbakhx2s7n - 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(cg )qyji87ci+ o.e o3+ anejt speed 17.0 m/s. The object’s speed increases uniformlyeqig3o njo(8j .+ycie)t a +c7 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 movez + z bz,84szp *xbgfqle03*v (3rprgus in a circle, starting at the top, with initial speed 17.0 m/s.lfp(z *zq 4vruxg+g0b33ezb,z p*r 8s 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 t1y8kzq4 v-/ c ajo+ pu,.ihjlzhe bottom of a bucket. The bucket is spun in 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 j cqo4uh1+zvk,/jiyl8zp.a - 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.