95.02: An object shot23w ug2 aj)lpwn in the accompanying figure moves in uniform circular motion. ptju 2)g a2wl3Which arrow best depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterg0 dok;vyb36dgo (h) gclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exer k)gy go(hvo;bd3g6d 0ted on the child by the seat and belt?

  08.14: A particle continuouslx/eyz;f i;u, ) d lzv;h a.7unv7.wltcy 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 t ;7dvz/chxwliu.vy;.7 ea,lf zn; )upoint 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;k 95iuh-ui ;w hscn6t 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. Pois5ktu un w6ih; c-ih;9nt 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 constan:yh67qbumi buj nm.-1 t speed around the vertical circle shown. Which arrow best indicates the direct-1.mijh:6 u7 ybq munbion of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected tgl 85c ve nwa.(2v use;+*usafg;, fmto 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 twirliwvmts2lug(f nevfe5*g ; a8;c,+us . ang 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 sp z uoiokif209-eed 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 ai io902 zuokf-cceleration of the car in traveling from Wto X?

  08.35: Astronauts on the ms l3uod-: r11fw a8tlMoon perform an experiment with a simple pendulum that is released from the horizontal positi3 tlsr-1fwauo:m ld 81on 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 -tmdr yk,7dp*k qv ghxg.+8 x42.0m from the center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5.0 seconds. The cgg -8vhtk rx 7 *ydxk.qd+m,4poefficient 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 in a circlejhoqh2:2lx 8xd 6*wr u of radius 0.5: 8rdoh 2ju*2xwqhlx6 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripircnyzq5z8xyl+- sf 2/ 9fu;retal acceleration of an object (mass = 50 g) on the end of an 80-cm s+/8r fq 529x-;lycunrz izsfytring rotating at a constant rate of 4 times a second?

  09.24: A point mass twvm 2a crn++8moves along 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 +ncv mr28wa+ tmass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled in a hosk8vv7o/pc 9 nrizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the b8v/nk 9o7s vpcall during each revolution is:

  99.22: A child whirls a ball at the a x* sz3w5d3i2wk p*ua6 ldsop:/y2v lend of a rope, in a uniform circular motion. Which of the following statemen32:v zad/6klox li *wyap 2dp3w5s*suts is NOT true?

  00.19: An astronaut in an orbitdx .xsqs3 vobj s* )3gvd,z09hing 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 tension in the string is F. If the mass, radius, and speed were all to double the ten s 9bxov.3vx30ddszhq*j g s,)sion required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until they)r8h-we 3c83p wrsun 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 n c-3hu3w re)yp8s 8wrcircular 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 r.--yfeu 37k oo.lyjmthe 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 ykyo- o3f7-.r lj.meu to feel weightless:

  17.10: A 2000 kg car moves over a +in3bq. +k.cyujv ; vdhill 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 qy.u vv.;i3+ j+dnbkcm, 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 isb)rg/yh3 eu3p moving in a vertical circle at constant speed. The magnitude of the net fo3br/ )ge3yhu prce on the sphere

  11.47: A simple pendulum of length Lhasa pg65smyxca.q9 h. . mlroint 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 fgy.sqm6lh 9.cr x5m.aorce 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 towr trv vrn0326 a string forms 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 string (T), the gravitational force on the mass (W), and the net force acting on the mass (F) when thev30wv r6trr2 n mass swings through its lowest point?

  04.41: A centripetal force of 5.0 n/77a opkj*n tkewtons is applied to a rubber stopper moving 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 frequenco7*/pj 7kkan ty f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to an ideal * wb+6eskb;y0 hj yl(zhorizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this lo0+z6w *b(eys;lkjby h cation 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 1 4tl 2pwlj3eein a vertically-oriented circle of radius 0.75 m.ll43t1ee2pw j What is the net force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled Xcep 9: 7baeqp bm+y2z,zz) nq5 andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the p+e:a pbmc2nbp 57qe, 9z)yzzq lane 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) 4n eg(g--ju6wenrww cc;ok) to the end of string and moves about the string’s fixed en wew)46j( er- wng;c) oug-kcnd 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 circula 8 ng)pk7 )aokc9o4xekp.b 5jnr motion as shown in the figure. The string to which the mass is attached hxgno .e4pb n 5ko98pk)7)cj kaas 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*1yl vlja)ed2.0 cm from a horizontal disk’s center. The disk starts to rota)d2 *jaylevl1 te 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 attached2mcij 9p )+x nij*j565dfes us a distance R =1.75 m from the fixed center of a disk as shown in 9jp56mjj i+ 5e)f2csdun *is xthe 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, with initial smqzy nj8 pgtrq4wi0/) c,cetf28 6r/zpeed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise throu8ct8 qzzcgr4qi m jf6et2n py/),w/0r gh 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, with initial spe4iag cc :p. zfn/4nn.ng29gshed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise t4fg nnc.a4: p /gnzg.nsc9h 2ihrough 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 bl ee+n;l*dc b5zock rests 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 enough for the block to remain in place in the bucket. When the bucket idzb+c n *5e;les 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.