95.02: An object shown in the accompanying figure moves in uniform circula rgjaoh/m 8ke2ru; lerpo5: +dev. 77f+owxp5 r motion. Which arrow best d d:ovrwrg7 ah25e+ upm r5 xpo+ f/jl8;e7e.okepicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seatm9n qwlub+oby 7mnm1-3v-i p) 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 b 1mbinv oulbm-)w9pq -my3 7+ny the seat and belt?

  08.14: A particle continuously moves in a circular path at constant speedts k /j+e.-l;u1oobam in a counter- clockwise direction. Consider a time interval during which the particle mob ojlks;et.+moa1 / -uves 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 continu.fia cdfaxmv . 4z.0p2-z +37wdjekvaously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves alon7vzdw20a f df-k.a+.a v3je.im c4xz pg 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 clockw7h ekck7v1o1uise with constant speed around the vertical circle shown. Which arrow best indicates the direction of the 177kve1 u hkcoobject’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small massm1gj +d7p x8ub connected to the end of a string counterclockwise in a horizontal circle above her head. The figure shows an outline u p8d+jmg b1x7 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 co+swfyp0ov2 9 anstant 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 thef2 awoys+9 0pv car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendulum thl/nu)6*5( vdqh1gg( ddbo kuaat is released fromduvoa g)1hbd*d6q k/5un(( lg 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 2.0m 55zcs)o 3x gtj iv+i0k8dci(xfrom 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 fricxj ( cc+50i8id3zgvk si tx)o5tion 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 t2l; oz kt6/sh8lm lw1io keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless s 8 llmt6wzh k12o/i;lsurface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of anp; j6+;; vbv o,cnvmcw object (mass = 50 g) on the end of an 80-cm string rotating at a co+v,vwm;j np v ;;ccb6onstant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.8m wkj/mm ox;cht9,p ( jt;ith a constant kinetic energy of 128J. What is the magnitude of the net force acting on the t/c;jj(k; o9 thmpmx,mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and wd0ap,5uq;6ud 7j gw vlhirled in a horizontal circle at a constant speed of 6.0 m/s. Seed 5d ;ul ugpqw0,7vj6a figure 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 rope, in a uniform cir7vfz: wqw 8fvo:gl 89qcular motion. Which of thg89f qw :zqlf:v vo78we following statements is NOT true?

  00.19: An astronaut in an orbit-9c(stz ac5 mjing 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 tsat c5- jm(9zcension 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 length L to which it is cv-u9pv/ lfqa,5w jt9 attached makes a 90- degree angle with the vertical. The mass is released from rest and s5q- lc 9u/t,jvva9w fpwings 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, see figure to thx00zwz,: jj0zvt k5a )hkb fa(e 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 0(ja)0 j: bk fv0,za5txkwzzhis most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12uf vq +1:s-gnzdnl31z .0 m/s. At the very top of the hill, the shape of the road can be approximated as a circlz1nln1sd: 3u qg+ -fvze 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 ver (:eq-zj5h+zf enrq3ctical circle at constant speed. The magnitude of the net force on the-hjq53 fe+rz : (qzenc sphere

  11.47: A simple pendulum of length ys3nc+1gc ai1 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. Lecaycsgn1+3i 1 t 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 arc (point P)?

  16.32: A mass connected to a string rvk /skad e 4zr.)jhap1frd812 -j;ubforms a simple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude of the tension in the st -krak2h1vz;s/ 48f j.j bu1dd)erparring (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 kyiudq: -/)4 8wx drlwmoving at a dd ykux4:qrwilw8) /-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?

  05.28: A mass, M, is at rest on a frictionless surface, connected to an ide7(hxc e6zod+d 8px(cd e0z/tial horizontal spring that is upstretched. A person extends the spring 30 cm from equilibe8x(d 07 zd(co/ezphdci6 + xtrium 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 speed of 3.24 m/s in a verti/xvh( 5lib6m tjj f59ecally-oriented circle of radius 0.75 m. What is the net fi/lbhx5 tev(j 9m6j5force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andg8 gj 7wba4 ffc8*xe/xY) are at reston a horizontal disk rotating at a constant rg xfabecj88 47gw xf/*ate 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 endfm w)) mto)7c:xll.ml of string and moves about 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 angle xmc)l wl7 o)m:f)lt.mof $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular4bxfhsc +/va:bt 12e k motion as shown in the figure. The string to which the mass is attached has a lengtha4b hvkf/sbct2+ :x 1e 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 ee 528wdr/kzq2ty2fk. vyy ,srest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angular accelv22 2tyk, 58yyde.r/wek zsfq eration 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 d0f-4lvayyi3 g istance 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 ay vf0 3giy4l-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 7pi eow8f p yb0k92l:gspeed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise thrli fp:8bw72ey9p gko 0ough 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, startinelx3 xmhq1 1qlnhdp4 t+;hm9* g at the top, with initial speed 17.0 m/s. The object’s smh1tl3 dp+meq49l*;1n xqhx hpeed 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 rests at the bottom of a bucket. The a w0z7dh6cyv);e5i :qx2( creeg-u vtbucket 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 in place in the bucket. When the bz-dh0r7vcg v 6ew;x:auei2c5qty) ( e ucket 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.