95.02: An object shown in the accompanying figure moves in uniform circularjo 1b el1ng fs3k4+lgc tk*ok(p;*8pw motion. Which arrow best depicts the net force acting ogonb 1tlck(w8ge;p f 1kp 4s3k loj*+*n the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates cou mxqe 3:n; *zus 5pg6vyrdq3i5+p/kwinterclockwise atm:s; +kvi/dq wpunep3356*z rgyx5iq 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?

  08.14: A particle continuously moves in a circular path at constant spee382nf lgqk,sl8 lhg7kd in a counter- clockwise direction. Consider a time interval,k7sg2lhnl3 k8ql8 g f 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 velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant spee, vr )ab njsa97tv7p/ld in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular path from point P to p/ bjts,a7 vl7)a9prnv oint 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 rs- i7 )y4ja0vdfjih 75q7zax:ooz1 r with constant speed around the vertical circle shown. Which arrow best indicat ixiy) jahafo7d5 74rsr -j0q 7o:1zvzes the direction 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 cou;,bhe8r(qai4 30cdebjobd 7k psf3d+ nterclockwise 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 labelebh p8 j +kd0( fae3d4cire7,sd;3bbo qd 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 aa zzpoj.zg c02 ) /8v5usuwfn2round 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 accelezf czjawup 8o/z5u20v n)g2. sration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perfsk6wk-w v +h 0,t1nuaaorm an experiment with a simple pendulum that is released fromtawkna+ su,61w0k-vh 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)0a5 (7oe zmbgqgbo ()t z*)gjz point-like object 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 coefficien (je(mg7z)5qg)gtbbza o o0 z*t 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 necessary to keep a 1. 0 kg puck moving uue/:ff6p xr1 in a circle of radius 0.5 m on a horizontal frictionless surface wit /x ef:1prf6uuh a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g7zx + fc2*4, p,fbjdyd2srejv) on the end of an, zj, ex2jfydfd c7*4vsp r+2b 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular p9 * jnpn5v22iyd2uqssaz +: lkath of radius 0.8m with a constant kinetic ad2 jl:nsq9kzn*2p+y2 siuv5 energy 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+ hjy8a 4*gv8z)6b cdrwlyte/bmk j19.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figum/8j8be9a jl+zc4k6tg r1*yh)vb d ywre to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball f2tcd ,-c l+clat the end of a rope, in a uniform circular motion. Which of tlld2c -cc,tf+he following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mpp51h.s,zxsu c*qk s*ass 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 Fs51u,*pp*. qzcxs skh. 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 seoue,cn:/6slps7 : wetring of length L to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest an 7,nou:s :w/epes6elcd 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 terrdg gl :q5o3y4cain, see figure to the right. Assume the car has spe co:g5 yd4gql3ed 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.yut,5m2u vsg:22 fgeu At the very top of the hill, the shape of the roau v2,e 5suyg2f2mutg:d 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 upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at constpqo7 dam)8t6 zkrv 3.nant speed. The magnitude of the n ramo8dt nq)kp7 6vz.3et force on the sphere

  11.47: A simple pendulum of length Lhasa point mbshco:c)n+v ;ass 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 amhs :cn+;c)ov bong 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 mass iw9p 3f itc7,-a yybe5is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks 3,ceb- fya wy7itp5 9i 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 is applied to a rubber stopper mo/cdof-nxb-g,no( c(y ztlc 3n8:g+j yving 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 stoppe8cnfgbn,3gcyoc d (z-l+ j( xnt/yo:-r?

  05.28: A mass, M, is at rest on a frictionless surface, conn a 8ul/epnqz0,ected 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 it is now doubled to 2M. If the spelqz 0a ,u8/npring 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 co1zxqwdz,jc) invyraeu343) , nstant speed 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 t, 3ra3cy) x1zzdv)4weq,uijn he circle?

  14.23:Two small identical coins (labeled X andY) are at res+iorw8p ;ylxvx5 .o, yton a horizontal disk rotating at a constant rate about an axis perpendicular to the plan85xy+pviyorl w .x;o,e 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 andeq;p+l +ort8 v moves about the string’epovt;+ lr q+8s 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 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 sho 4dos w awgo r5ui/)(r+9,i(vup e jxxw;xu3(zwn in the figure. The s;+wx)rx4w dgu e 9vop5so w(ii, uxj3/(u(r zatring 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 h llu)q0r buc*)p(ro)wz6 lc/ is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center wi/ucz6q) )wou0lr)lhr bp(c l *th 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 m fromnqk9,qjo hz65v ,z3d p vo*t6o the fixoh3pznzq5ovd66, 9 , jvtk*q oed 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 in a circle, starting at the top,7rud2,f 3 ks3vobhnl) with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an d7skbo hl u23vn)3rf,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,u )rra:uj ab2, starting at the top, with initial speed 17.0 m/s. The oaba:rr)j uu,2bject’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 resr6zbwr ttlri3 hb s. qb0:xl9p.f9 00zts at the 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 e:l.bz09 06t.qhrprz9 lw3it rx 0bsf bnough 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.