95.02: An object shown in the accompanying figure movej*t oj)o7j.d rs in uniform circular motion. Which arrow best depicts the net force acting oj.rjot7* odj )n the object at the instant shown?

  05.31: A child is belted0jri iyru1d *4 into a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total jr4 1*0r udyiiforce exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular pathi+zw2o a m1- bh ghjti,;7b ;:k:pxsyk at constant speed in a counter- clockwise direction. Cons,mah ; iw s1:bthp jbk7z: o;-+i2kgyxider 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 patdq0e2jj y// ddtgj8o 6h at constant speed in a counter- clockwise direction. Consider a time interval during which yt6ddgjqd20j8joe // 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 th ;kpfh1-8 d-xmjoz gkh0 h)b*he vertical circle shown. Which arrow best indicates the )jz1x* h8kb0g -khh;fomhd- pdirection of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string cou)op36n tr n;q*eqqm7anterclockwise 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 labeled P in the figure, 3 6oqm*te nap;qr7qn)at which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speed around a horswb z jomx-:o9)bz2+ gu4m 7jekeshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the directx)2mgozm 4k-9eo u+jbwzj b 7:ion of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendul)p u,kihf-n t4h a;l)tum that is released from the horizontal position at rest. At the momentuh 4ap)f- i ntlth,k;) 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 from the center of a (mijuhu:b 6 j:rough jm jbi::uhu6( 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 friction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force is necessarr-2eae k;eh c1y to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface withea2e-1ckr e; h a speed of 2.0 m/s?

  05.03: What is the centripetal accelera d+f /icyxl:+jh*/2x5 cvwguo tion of an object (mass = 50 g) on the end of an 80-cm string rotatic +gcu / hxj5+v*2ix:lwfoy/d ng at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of. k6ob. bev)(j7qoqnb radius 0.8m with a constant kinetic energy of 128J. What is the magnonb76e(bq ).vb .kqoj itude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ballc9mf1pky 13z ;y7 oqbp is attached to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on t;cppq71mo fyby k z391he ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular ymvu3( ljr st*g j6t/3motion. y( l3ug jv3sjt6*/trm Which of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass m hq-/wo269bkqyc pn k,to a string and whirls it around in uniform circu2n qqp/9w hocb6,-kyk lar 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 outward aimq5 -7tdgga)czv,g3; zc h)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 isgciq3 gc7;d ,vga)5 h-ta) mzz the tension in the string when the mass swings through the bottom ofthe arc?

  94.15: A car is traveliezz nzjrm:6p*76qq8re/6rx ks /gv 6png on 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 likely to qg6z/r 8*pz 6vx6me z/e: psnkrrq7j6feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0 m/s. wqvjv * xvmiy7/6mbl 74gim 7;At the very top77*v mviq;7m jg/byv iwlx64m of the hill, the shape of the road can 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 circl3hn, brx bb ypw*1b76le at constant speed. The magnitude of the net force on the sphewbrybx*6l,bp 1b 73hn re

  11.47: A simple pendulum of length Lzdo(g ul4w6 /gl2qkk+hasa 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 kguzg(6lqo d /2 4kw+lthe 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 i wed xabobw hl3o;7qt q*/0.w(s released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude of the tensiond3 /o wxeb7qlb(*wtw;qa.o h0 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 it0 +-5jwis+xsu(g q yls applied to a rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, bxy-wj sq+gli 0 tu(+5sut 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 w43 4nkrzm lc 9u7k4gej)go5 tfrictionless 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 uceln59 w zg7mrg4t4 j3k)ok4brought 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 4hj1dk-v+ 4 6* // lxxclnhr:zoepypl..0 kg mass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. Whalvh1/rx jz 4 6lde+ycpohk/nx :*-p.lt 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 X andY) are at reston a horizontal dise/s./xf4oa l, hr5 a36on lbxl7xdv+pk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of the coins fr6/d na+vll. /5f bsr4,hxp7 o 3exaoxlom 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 nwf/ ox39 y6/b)o: ompf.n +rx/s rtcxstring 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 for:ry/)wor9o nnm/xpotf 3c/sx +xbf.6ms 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 motion as shown in the f5vwo+ vh w-re-igure. The string to which tr -ow-v+veh5w he 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 horizontaa. bjo1u*af) ajmp/y2l disk’s center. The disk starts to rotate from rest about its center with a constjaba*.)po2fj/ m uy1aant 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 R =1e5i5r -jaw gx g zj ,mq;jb4jy8t9:n*n.75 m from the fixed cente95tb q wny anjxe;5i j j*,z-mggj:r84r of a disk as shown in the 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 speed h:h.sp c:*tn x17.0 m/s. The object’s speed incrpt h*xh:scn.:eases 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 inc8-c 8,yg:ayvsnofa x)2*d dg a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through any doa)xs-ggvy8:c,cn 2 8da*f 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 buckek4m y) gnak g0g13y*q(ghah/6boh1t ct 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 yn)ga1k g3 ahht4qg0bcom1(hgk* /y 6fast 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.