95.02: An object shown in the accompanying figure moves in uniform circularl,o x 0-bc4rbyz(k 5yw motirk,o bbx 40 yw5(yzlc-on. Which 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 6 +mcjez+l07k0dq1hft st k.kcounterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on tfq1kjt++ltk6 7s k.deh00 m czhe child by the seat and belt?

  08.14: A particle continuously moves in a circular pat.m hk.ppw o:v2h 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 pointvo.w. pm2 ph:k 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 move,9;jceynn4l:9/bp. tgeupos s in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along9etn,o94spy;/ n puc leg:b .j 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 du7dqb9o+ d-hd//d q lspeed around the vertical circle shown. hq l +dbq -/odud/97ddWhich arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected t/l6m.xj2zahl ()xsapo the end of a string counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path aa62z lhxp .(j )mxl/s 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 speed around a horseshoe-shaped pathy1kl-c 1si dioyht89+g2wy 8i as shown with the arrows in the figure. Which one of the following choices bwy+8c y19g i i1-82 ohyktdsilest describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment wu13bi *ft mw8jp:1/l3jn levkith a simple pendulum that is released from the horizontal position at rest. At the moment shown in tiu/8wl3blt3v1e*1jm n pfjk :he 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-lpjs n 5f7nw5un e jc/v5(i+*rcike object 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 ob scn nuwfr5(*7v+5/ipn j ejc5ject 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 circle op-u/exrcom 8m.c 67zyf radius 0.5 m on a horizontal frictim- c pyme8u/6rcxz. o7onless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass 2dpapik, -:g h= 50 g) on the end of an 80-cm stri, ig-a2:dp hpkng rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontalbjll8m/35(,qhueri e circular path of radius 0.8m with a constant kinetic e 3u,mq(/lhr8b l5i jeenergy 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 whirled in a horizontal x6w3 : 2pzrd,rf+l)nda9ajx l circle at a constant speed rr29xd 3j l,)dn6pfaz :axlw +of 6.0 m/s. See 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,j dd0qx47s4u d in a uniform circular motion. Which of th4dq ds4d7x0u je following statements is NOT true?

  00.19: An astronaut in an orbiting space craft1 zl6nz5q ojg: attaches a mass m to a string and whirls it around in uniform circular motion. The no 5zq:g1z6jl 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 outward until the string of length L to ujt0dfn7wz w5 kb*0z1 which it is attached makes a 90- degree angle with the vertict*zu0n0 z 7wj51f kbdwal. The mass is released from 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 onfjecwrhf:5;0a d s: *ohhg2zh*:: r; kv1zdob 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 car is most lzfhh vg0or;afo :s jz1 cre: ;: *:dhd2kb*wh5ikely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.t5evp)lo k runjg 3)-d5d0/y g0 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 figurg)5le5d3kuy/) tjvnrg po- d0e. 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 l/i p659nv lhaa vertical circle at constant speed. The magnitude of the lan9i/p h6lv 5net force on the sphere

  11.47: A simple pendulum ohr vue 7+*g7ggc- (pku5539zsl cuvhroxg+ p .f length 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 strixc 3h.u5grlg gk+-u5(pzuh+evsr7 pogc 9v *7ng 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;n2ss *9iwncm vsvo8, to 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 the mass swings thro;vnm2s,svwocs98n * iugh its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubbyv:)od 1k-mhq er stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller)d 1:qv mhok-y, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest onutep s+),rs- jkdz:n 3 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 cm from equilibrium, what is the neces:edk3zrt +s js-u,)p nsary force applied by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant ()pqez1 ) mdvnu 1parrzw0 z1k77:gzispeed of 3.24 m/s in a vertically-oriented circle of radius 0.75k vn)p rz 0 urz1gp(:ied7mwqzza)11 7 m. 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 (labelgm i*np7g:)v*/ jnt*ixb zkm 1ed X andY) 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 distance of the co) g *tignb km*mxn7pz/ iv1j*:ins 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 c+ wp dcejy l*x3**( dywhezy1+f-0ijfonnected to the end of string and moves about the string’s fixed end in a conical motion with a constant speed of 4*f wycl+xdjpif e*d+(13w-y 0y*hze j .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 motiopfbpx es(x8mhlu/r3u2b, )-j n as shown in the figure. The string to which the mass is attached has a length xbfepx-lrsj h, 8)/b2mu( 3u pof 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 a d),zb jrg.9addnj r) 5sv6i.kt rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angulard9k,jza5s6djbirnr )v ).. dg 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 objectw a4 vt8qyu)*9wyc0 pz with mass M = 2.0 kg 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 wittc)pw49z0 y ya w8*vuqh 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, wi. .m/ajaa 0d;nluxe 2nrt/qd.th initial speed 17.0 m/s. The object’s speed increases uniformly until i/qan /jrut;dl20ea x...mad nt 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 0 n2ivwf sfld v ( iwzczrc67f 3kp1lrv*q/9*9the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterc2 f n1ffd 9cw / 6( 9wpkrrllqz0scv**iv7viz3lockwise 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/+;*;mscz tig(ky uds 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 movesi;cyzs*s +/t(; dk mug 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.