95.02: An object shown in the accompanying figure moves ino l cf:zk,p;*h uniform circular motion. Whicl;: hp,*cokf zh arrow best depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheedw q,;+4w ynr3 sv*eodyea1z7l seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the c7qw1o4 ;yze d3w,yd r vsn*+aehild by the seat and belt?

  08.14: A particle continuously moves inn/sxzsya si.9a0;w6wu8ug, u a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along thisusu .,6saazgsnw9w i;/u0 xy8 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 conti 4of)svo3i-gw nuously 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. Point Q is exactl)fio-4 vsowg3y 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+5t.4 bezyubq8yjy7t constant speed around the vertical circle shown. Which arrow best indicates the direction of the 7+q u5te4z byj8.yytbobject’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string counterclt+gy 24aw fnjh 7rptx2 i(si59ockwise in a horizontal circle above her headiht f2yaw9+pxj427rns it(g5. 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?

  15.23: A car moves with constant speed around a horseshoe2a0)i,o85bo girtsdfwdg kf z5fx y (4 uim+/.-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the car in travelig f8a gdo5m5 s i( .dyxz,0ub/)kr4+owit2 ffing from Wto X?

  08.35: Astronauts on the Moon perform an (gz /b;xoh8tk experiment with a simple pendulum that is released from the horizontag(xtozkh8 ; /bl 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 rests 2.0m from the center of fne+fuj.c sx-wc.a 6i ov;, 4ra 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 ofs v6 xn we.+ jcofufa,;-cr4i. the force of friction acting on the object?

  07.19: What net force is necessary to-+ edn schy(k*jk 7,op keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal f-(n kcky7oph sd+j* e,rictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration ofopj.r)vfi-u 4 an object (mass = 50 g) on the end of an 80-cm striorvf4u-pji) .ng rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m with 5w4 s 4 kba1f-lopdbf1a constant kinetic energy of 128J. What is the magnitude of the net force acting d f4o fbp-bsk4a51w1 lon the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and k fl7jav5m))o whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done)l)5f 7jaovk m on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform bjj*dd5i/ m7qw- gk5pcircular motion. 5 jb5*qdw j-igkp7 m/dWhich of the following statements is NOT true?

  00.19: An astronaut in an orbix66x 6ia qjyu)bz iydk(7 e;a1ting space craft attaches 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 6(j6i;q 6 bayaeyix)x7d zu1k 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 Lx6g vpw:ptp /(scb( ;u.sra/i 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. xrcg u (/s:vi6p /;aw(ptsp.bWhat 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 terrain4,4zz t hdc+fm, 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 tozh+mzf4 4t,dc feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0 m/s. At the vxgay1 ;*(kyx oery top of the hill, the shape of the road can be approximate kx(;ga1xoy*yd as a circle with radius 25 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 k+v g5:k oyna++j, reoat constant speed. The magnitude of the net force on the sphev+ nyra:eokjo5+, g+kre

  11.47: A simple pendulum of length Lhasa point mass M releasedi8ogbjwmedrj i(;*( xjv6y2+ 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 mass swings at the bottom of the e8r jx (o(i6j g vi+db*j;my2warc (point P)?

  16.32: A mass connected to a string fzsqkxh;; h7yt/9 eh i(orms a simple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following cy ;x/ s(ikh;th7he9 zqhoices 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 zib1gk7ab 9e cv b,6r.m+err ;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 the stopper?mk vb. zbe, ri1racg e6r7b9+;

  05.28: A mass, M, is at rest on a frictionless surface, coso566ps*a i6 k3mr 8iu3pyezb nnected to an ideal horizonr ap 6s 3p58bmy*uk6o 6szii3etal 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 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 5bf.u.ueofz. +nnkc)e o-tx7a 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 mkofn)tob+ 7. 5xu- n..zf ueecass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are;pwwk)/9a q*ap1 u wdq at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and throughda 19a *p u)qw;wp/qwk 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 abouilb:km:rr,zs43zf( vg;t xp7 t 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 b4(mr3i :sz7;k,xlrf t:p v gzangle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in unifvv ,c29)aua igorm circular motion as shown in the figure. The string to which tgui)v cv2a9, ahe 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 ho 7 3cigz*ta4rdodz l46bcr 2x3rizontal disk’s center. The disk starts to rotate from rest about its center with oczrg t 43r*4adc6z3ib dx72la 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 2io5 oy .bde4fkg is attached a distance R =1.75 m from t5be2yfd oo4 .ihe fixed center of 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 in1 udbq9ggghptw b3;,*ghtu yq 110k)s a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through a b, pws g;u tqhqg9hg3u gby1t1*)d10kn 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, start jajwd * d5 tgeuk6dx:e+;ui,0ing at the top, with initial speed 17.0 m/s. The object’s speed increases uniforg:dej5 au +dkxudt6j w*,0 i;emly 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 tyb yvuw yv jr5u5 *10stfv*33of a bucket. The bucket is spun in a vertical circle of radius L by a rope. Wr5 jfwvuy3v *3tvub1 05yys *then 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.