95.02: An object shown in the accompanying figure moves in unifown6/)n nc;b il5q) 1 v dd/fvbdszdu00rm circular motion. Which arrow best depicts the net force acting on t 6q0 /1 sdw)bdvnzn0v; fincul)b dd/5he object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclockwweb;5imkho v(d 1n5wn(- a y0yp( f(s t-/femuise at constant speed at an amusement park. At the loc0 (smun5(i;51 bt (awe/yfe h - v(m-fdywnopkation 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 rgr u:p lv9-u(piy; e9 ;kkb.xf)f3nsspeed in a counter- clockwise direction. Consider a time interval during whichi;kl9r.;p)p f(s rgynf:ebkx -9v 3 uu 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 ci yf492; 0cerjrsh:pxf rcular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle mo: 4p2cf; 9yexrfh0jsr ves 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 verticayda/ibqg- j9 e6h 4,eml circle shown. Which arrow best indicates the direction of the object’s i,4 iea/j-6mqb eg9hdynstantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connw*lqweib1 9y5ik *-raected to the end of a string counterclockwise 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 pakqbr*-a 9 iew5w 1y*ilss 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 path*q:,:o08xrgnp ,t lfxdkb :wm as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the:fr m tnp:8 d* xobx:q0,w,glk car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendulum thm3 ;upnq)(( ux ata0 2 ;75uissimhhpeat is released from the horizontal position at rest. At the momeuius 5 ue)mq(a0t (np3hm s;2aip; 7xhnt 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-likmwd7s5ej 3(/rj9govdoi( xb:twds (lj (6fy+ e object rests 2.0m from the center of a rough turntable as the turntable rotates. The pejf sysd :(w7 5twidgolbjv( 9(3xde(6+jr om/riod 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 force of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 k ) w9:whjzdozg/8lui9 of gs13g puck moving in a circle of radius 0.5 m on a horizontal frictionless s89z9:s fo g hw1dug joi)3lw/zurface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceybjy1u*l n:ub.h jc +a07qwq2leration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 tiwc7 jqy.u:j+lb u102hyn*b aq mes a second?

  09.24: A point mass moves ad3 ;bh:x bz9kp*ece3p long a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the 3kzbdp3cpex ;e 9:b*hmass as it moves?

  96.24: A 2.0-kg ball is attacv1h8(f5-xo5jihze:2 y3tzdh . zeqpf hed to 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 ball during each revdxj he:5p 5-ffqozei2z8vhhz y1.t3 ( olution is:

  99.22: A child whirls a ball at the end of a k +czvz f)wq2l9qp:d)rope, in a uniform circular motion. Which of tq:+ kql92zzw))fc vpdhe following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a stringa2(fs bx8 z uo ux(1/3hqyulkss) 2d)e and whirls it around in uniform circular motion. The radius of the circle is r, the speed of the m2/usfu)e1 l sazyoxx) sk 8udq2(3(hb ass 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 lenglb41vw x 4xslnr07 .xoth 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 anvol404 .r1 bxl wx7xsrc. What is the tension in the string when the mass swings through the bottom ofthe arc?

  94.15: A car is travelsg:i o8h unm56ing 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 cargm uinso5h 8:6 is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill,m qxfxse ),pe1) kg-k,dfw5n 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,kx mgfp-w k ),qe 1dxs5,)fen 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 consth o,09eembqx8 /s)v-flzg 4b fant speed. The magnitude of the net force on the spherf-gm/h oqbz )4bl9,s8fx eve0 e

  11.47: A simple pendulum of length Lhasa point mass M relemyfdu-k- )e)s l-r ; (mrtxns9ased 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 n 9( ymr;sx dkfe)--s) m-lutron 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 st+4rwvw sqn4f8kf7h x )ring forms a simple pendulum. The mass is released from rest and undergoes simple f) rwsfxh8q4nwvk4 7+ 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 mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber sd) k aj+4ye i+fhmjn0ei )*(patopper moving at a constant speed in a horizontal circle. If tfid n0mk4)aa+jjh e+ (i e*)yphe 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 frictionless surface, connected to an hhi 58ih fen*2ideal horizontal spring that is upstretched. A person extends the spring 30 cm fi * f5e2h8hnhirom 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 a constant spey z2- e+ grx8tw(9oaya)m/lv eed 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 ig8)ew er/zy2ym o-t+v9xl (aa s at the lowest point of the circle?

  14.23:Two small identical coins (labeled X x h62. 0mamqr- )idc lnnk7sh9andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through 60 mi)9haskx7ldqc-hm2r .n nits 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 ispz,)bgru, 0( jc q8upy connected to the end of string and moves about the string’s fixed end in a conical motion with a 8zcug)(,bp yr0jq u,pconstant 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 shown in the figurb 8k1z3pcbw .wt9:q tne. The strin9bptw 1z:w8cqt bk3. ng 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 c)rhb0b/mc reqzn7o ux- s6 8b;:grga+m from a horizontal disk’s center. The disk starts to rotate from rest about its center wx;7/+mo) rg-c : bs0 rrbheq86zgba unith 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 =bx:)dnekc8ho72c -of3mk x8h a ( s(tm1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with constan(kkmbfah xc on-(m72ds3 o) t 8hc8e:xt 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, star h vmwr86r-/dgt djt8o,s 64hvting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angle of-og8,wh4rs rvdtdm8/6tv6h j$55^{\circ}$. 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 tkw5y8ckg on 136l5e ukop, with initial speed 17.0 m/s. The object’s speed increases gk 5ceylk6k5n8 wu31o 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 buc,;a uy pp3cuk,ket is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest point i p, ,cuu;paky3n 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.