95.02: An object shownv n+aczu (/jym glj989 in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object atgvnam jju(+l9c 8 zy9/ the instant shown?

  05.31: A child is belted into a Ferris Whq,*54 eu y,angs 0zytyeel 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 child by theyg,0zse a4 5tyuy* nq, seat and belt?

  08.14: A particle continuousl amg6u*bfc x9ax,d,q/y 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. Pqbgx a cfma,dxu6*/, 9oint 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 7ac7rqr)4ur ,r mp 8zvat constant speed in a counter- clockwise direction. Consizr,arru 4qv8) 7p7 mrcder 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 around the vertical circla(*c;i2ox:sv92qu8u zrf oe ae shown. Which arrow best indicates the direction of th fa2 x aq(29 soue:cuvo*rz;i8e object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to 0 0x :9 w-rwa1spapwdathe end of a string counterclockwise in a horizontal circle above her head. The figure shows d:-wpxwr00 saa91 wpa 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 (f*aq8t )dhvg speed around 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 acceleration of the car in traveling from )d *q( vga8fthWto X?

  08.35: Astronauts on the Moon perform an experimen yk9e l5;q-ezmt with a simple pendulum that is released from the horizontal position at restq5ke-melz9y; . 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 obj(cdo 7j72fnd //ncpizyca 98; pjhfl9ect 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 frictio 2 cy8/7jpjzpn;9(9cnfd i c/7odlhf an is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force is necessary to keerycfhi ;rxs 93w6g2g 9p a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fricr29xwgc93h yf ;sig6r tionless surface with a speed of 2.0 m/s?

  05.03: What is the cento7uo8.y vfj4l*l u nm;ripetal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times 84l monfouv y.lj*;7u a second?

  09.24: A point mass moves along a horizontal ci2q5f( kjka3pwrcular path of radius 0.8m with a constant kinetic wf23qk5( ajpkenergy 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 0.80 m string and whirl1,;fea0umqr kn m c4c1d+e9kaed in a horizontal circle at a constant speed of 6.0 m/s. See figure to thakm049km1c;ac n,ued r1f +qee right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at th -z+1ad sr 9uys+rl*jiy,jyb0e end of a rope, in a uniform circular motion. Which of the followiyjdiy++j-09r l1*a ub rsszy, ng statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a m6qbto .j:tt5f;uq -astring and whirls it around in uniform circul6 -m.;tf:quttba5 oj qar 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 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 .,niwqf4/bsttk-.l-frwjfg m, )m;toutward until the string of length 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 throub n-f,m w,..ifqr)/sgtl ftkm4jtw; -gh the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to th6rd lbcr 6e0 *(fwa5r 7 *ha3c qa;0ainj;qzmve right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R.q3a5 avrb0q0ah 6d clz 6w(cna;er j*;fr 7i*m 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. 7z 0l g0jk3iglbzl +7zAt the very top of the hill, the shape of the road c73lzjl kb+ iz7l0 0zggan 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 constgbwy:ew0,lz ba: 08l zant speed. The magnitude of thwbly0zag80,lb ew z ::e net force on the sphere

  11.47: A simple pendulum of length/ l(gofx ycfi /ri/;*n 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 of the following choices describes the relationship among these forces when the mass swings at the bott y;//r fon/xiilcg( *fom of the arc (point P)?

  16.32: A mass connected to a string forms a simple pendulum. The+*pvs,ml:r r m u+j(gi mass is released fromvs:r(jr+mmi u+,l*p g 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 mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stajec p5rx3k dwe;3 22xm9fke.opper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what hapdefkx3w593e; a x. 2jrk2cpempens 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 ideh 0vyu/ yg o.p/8audn.al 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 equil/ ndgy80u.y/.vaohup ibrium 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 speed5.yv c u:i0n )otyy/fer/s :zj of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass w/vyou/c:y0 nie.jtr 5) zf s:yhen it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andc+)9e g *dc- :ovslnlaY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distannv9c -*s+dg ca)loe :lce 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 s 3q+vh 5-klvp p266det5egtghfs6 n9p tring and moves about the string’s plnd5 pgt9q +k -gv6e2 6htp3 sf5hv6efixed 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 unifr.uy,f: 4-isbz4cqz ( g ag7kfgyc.a/ orm circular motion as shown in the figure. The string to which the mass is attachai,skgr/ 4.z fbcuc q a:.-f(gyz74 gyed 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 m**. y a1)/-rjo+auvi7 aymj3f mbevq yass 11.0g is at rest 30.0 cm from a horizontal disk’s center. The disfa .)a**7ym1ja mbj / yv+q yivuro3e-k starts to rotate 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 ,h,lb,5ycof ku 8 6c7wtz -krq6a1 brukg 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 accelerationr wcr1l7u68cz o,-k5,6bt auhqkbf,y $α =5.00 rad/s^{2}$ 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, start2yb2 8 5*xiu/tu(uond w)vrboing at the top, with initial speed 17.0 m/s.u)wru5(2d vbboy on/t ixu2*8 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 final speed of the object?

  16.40: An object moves in a circle, starting at the top, tek)wr0v bim+t/ +*hjwith initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through aer kbw0v/i t+)tmjh*+ n 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 axfpjgcg . pla+k( g7e5 *b)m)ht 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 enough for the block to remain inl g5mjhegx(ap bc .p) k*g)7f+ 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.