95.02: An object shown in the accompanyinoj-5-y;z.x3lzcm w**fcq iy jg figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the insta -.mz ;j wqyzc-j3 coyxi*fl5*nt shown?

  05.31: A child is belted into a Ferris Wheel seat thatu/p.e) su:3 q;ls tsfx rotates counterclockwise at constant speed at an amusement park. At the location shown, which di)/ tuss l.s uqe:;fx3prection best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuouso81zaituc9 s j u6w-ub -wg:l1ly moves in a circular path at constant speed in a counter- clockwise direction. Conlb c :z-j1wow 8ug 1t6-a9isuusider 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 velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant speed mc.x*/ n e3gp iiqw+r/in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular path from/e/wnp.q3+i x i*mr gc 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 so, m m89 rtb;s1 i)w:0ugffbqwith constant speed around the vertical circle shown. Which arrow bru ws8ffg 19mb)t:o0smi; ,q best indicates 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 af+xo evsm5q6sn,hmd m z:w+/86atm h 8 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 pass through the point label6 s8x tdh6m/qv,zm: mfm sow++5ehna8ed 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 7p4x+i w8e)xt15vyu uf)ddlx 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 acceleratixd+) xlpvf8uy15) ui 7d txwe4on of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment witho hzlg+p9ypi.0, :p4oqhgd 1r a simple pendulum that is released frq0orp .+4p:y zoh,l g1pihdg9om 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) point-like object rests 2 stz)yalo9 ,4cd sl9two;2ly7.0m from the center of a rough turntable as the turntable rotates. The period of the syz 9; osl9 tl4clwyoa7, td)2turntable'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 forc.ix9nsi(84o/l -6vl-ayp p koj8kz jre is necessary to keep a 1. 0 kg puck moving in a circle of radius 0 l9joz-jpv4xspay /6ko(r8.-8kinil .5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripwlt 1m46zq0lc ((mry vetal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant 6zy m m(tw1qc4lr0l(v rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path x tr(t,wty ,8mof radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as it moves?mt,t8 r,(yx tw

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled in a horiyvw1/yoz8d) og/p ) iezontal circle at a constant speed of 6.0 m/s. See figuryz p/v ed8 1o)wyig/)oe 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 ropem) vgltk2jqajpp o3 s27r**l/, in a uniform circular motion. Wl vp7s)ra/m *l*j3qoj 22kptghich of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a st;wt+z6;bx7t7p/jgaiw:x sjvring 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 F. If the mass, rad i;z t+/atspv67b7w:j;xgwx jius, and speed were all to double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward unt) z9rxyyja m h11u5eo0il the string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is released fro1umyrzeyj 50 o1h )xa9m rest and 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 terrain,fpur -m41z: kw 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 tfpuw- km:z4 r1o feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0 m/.a-hri .k+rxf1wj jd ,s. At the very top of the hill, the shape of the road can be approximated as a circle with radius 25 m, as indj, r.k1ijw+a.r dhfx-icated 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 constan;b-q+v d4owge t speed. The magnitude of w; dbg e-4qov+the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from resa4 pd ze*zms i;*oqh3,-ka+fyxv x/t5t 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 ff,+hzk;yq5v- * s/3xz xaopmie4t* da orce 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 string forms a simple pendulum. The mass is release,6xwo +m3l-pj 5si 90tatf ifvd from rest and undergoes simple harmonic motion. Which one of the following chx03v-wfp5 m9lij,6a ttof is+oices 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 om;:qelvm-9)s wq rkj3f 5.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal circl3sk9j- lqv:w m m;rq)ee. 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?

  05.28: A mass, M, isqarbow8) 5 is7 at rest on a frictionless surface, connected 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 spring is extended back 30 s wb8a7q)r oi5cm 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 w1 k2d12n +jndtaq5rtj ith a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the 5+n2k1a1jn t 2dqjrt dnet force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (la ;q9t8xsv t,uvbeled X andY) are at reston a horizontal disk ,v xt;98q vutsrotating 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 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 about the strjxrmfhef02)iavrmbtw -5672-3b hqming’s fixed end in a conical3b7 rf wmm2ix6b )ma0h f5vj -q-hrt2e 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 l*tmeoe2 )zqz1s(xi 9qe;3ss motion as shown in the figure. The stoe x( *t;zsi)se 9qlsq32m ez1ring 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 cm from a /hmgl1 9ro7nw ucym3+ horizontal disk’s center. The dymugw lmo+h 1/7c 39nrisk 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 kg is attached a distance Rvzzaaw 5.eemho+: oy*2zm) 5a =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from h m*we2z: moa+5) ea.5ovzya zrest 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, with initial spexkyn hl501p/ j xzr4(saor 9gb4;c7m ied 17.0 m/s. The object’s speed increases uniforz4ba/ sg;xm0h(ckp y ior1 9r5x47ljn mly 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 cir pql2 djyc-98/vgl+9m uccts)cle, starting at the top, with initial speed 17.0 m/s. The object’s speed incrtpu/vgsy -lmj)l289+c9 dcc qeases 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 rest+2n kxofr19se3x ppi 3s 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 fast9xp31x i p+2r fon3kes 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.