95.02: An object shown in the accompanying figure mox mm 7 -m4wjclkpx5h,2ves in uniform circular motion. Which arrow best depicts the net force acting on the object atm mjp2xml4 w5cx7-,hk the instant shown?

  05.31: A child is belted into a Ferxy7 a0p,u s3 59e:r3aptvhi ccris Wheel seat that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direcr 9y ae5:7,cat3chp u30xvis ption best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path at consi(//htjl17ud4qgr u2 z,2k k cn1thnitant 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. t( zuj1/n 7crgkiu2h qkh41 /n, il2td 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, j:0oht7dy/fqjcta; circular path at constant speed in a counter- clockwise direction. Consider a time inter /y 7fdh; ,o:jtqcj0taval 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 acceleration during this time interval?

  15.07: An object moves clockwise with constant speed 5m+ ojt93j0t,ramq8kgrs x w /around the vertical circle shown. Which arrow best indicates the direction of the object’s in0,jo/ trkm x+ 85 mrwts3qg9jastantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string countercm of2dsa t p4tk79b89 l++edielockwise 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 7fmdkl9 p8+tti bo4+se29ad efigure, at which lettered point on the path should she let go of the string?

  15.23: A car moves with consta.:3kiwtyz8 zzr9pe g fl; r/hctm w032nt speed around a horseshoe-shaped path as shown with the arrows in the figure. Which onz23lgz y8kew; hmrp9f:twz0tc/. i3 re of the following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an e+j:sztwei9 qw k 9o):+re tjr-xperiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the di9-k ++tsw ej jqiz w9r:ot)re:agram 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-li o np1;nz n/m 05+c6.cg5 evub*tltwylke 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 object and turntable is 0.50, while the coefficient of staticlcozp+ ;1lv.g5u6nt *5ywe 0 mncntb/ 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. l f*o/h3e (po1jytx7q0 kg puck moving in a circle of radius 0.5 m on a horizontal ffoe1(hj/*p y7q lot3x rictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g) on th l5 lkn-+ll:ame end of an 80-cm strin-5km llaln+l :g rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal cirsp d*i* 7m f0g:lwsc1rcular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force actisr0 *7gp1idc fl m:w*sng on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m s- zf-aney (d r):65bpsi 2tnoctring and whirled in a horizontal circle at a constant speed of-e di5o cr)bafpytns(n- z2:6 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, x1ni.c*u dh r27 j4(t,jeddds in a uniform circular motion. Wh ec1n 4,*2td 7d h(uisrd.jjdxich of the following statements is NOT true?

  00.19: An astronaut in an orbit94 ht3r(ct )8um)ljq jb5kav xing 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, a)tc )vqj8j thl(xm9k4ba r 5u3nd 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 which it6z rr-fajm0 n9)dc fr wyf1b04 is attached makes a 90- degree angle with the vertical. The mass is released from rcfj1-09 ardmfn b6 )y4fr0wzrest 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, see figure to the righ lk. ;tv(z,6spvgds /rt. 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 feel weightlev;6 z/ gtk,dvlsp(rs. ss:

  17.10: A 2000 kg car moves over a h-vy bn vnuy-xv6 qj+4;vee: 96ygu x6sw-dy:zill 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 m, as indicated in the figure. enuy;g+4- :xx9jqvbvy wyd6n : v--6 zyeuvs6 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 vxkh1r1 x3zhxz /hg* 5a vertical circle at constant speed. The magnitude 5*/xg1zz rhx3 hh1xv kof the net force on the sphere

  11.47: A simple pendulum of length Lhasa pointnlb +l s h8v(s3aj8)yt 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 osv(j n8t8sa)hy l+3 blf 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 forms a simp* gjtiby6i*i m5y4zp+-dp nwh14 j ql1le 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 throug+y4jqm jhp1yipntd-*biiw1 5g64 l*zh its lowest point?

  04.41: A centripetal force of 5.0 ne m7rexk, q,j9zwtons 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, 9merq7x,zkj , and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to oi 7mrd4 b)/u g)s.tupan ideal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this location by applo/7 p4gu rm)du.bits )ying 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 zr)kk , 9fu1+* euplnz4.0 kg mass with a constant speed of 3.24 m/s in a vertically-oriented circlek1rufpuzk nz 9*e +l), of radius 0.75 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 (labeled X andY) ysxsu,ea ,+x lt;2r9 care at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the scs,lau9xe;+trxy ,2 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 abou wzth 65x0fr4ypzk,;at 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 f xhzza,5;wp 6 rty04kan 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 a+kirx3f8i.v m-ig2pc s shown in the figure. The string to which the mass is attached has a length of L = 3.00 mv3kgxr8-i cp i.if m+2 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 114 ebm dbk :07jq/-/(vklxiuc 2xeuz9j.0g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a co-/ez ebxuq4/ljj(xi 07m9v2:c kdub knstant 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 izq+gb;0gkp* b5 wgh0is attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotat*0wbbq+ 0gkgpgi 5;zh ing 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 top3fo,k c hw,ed-, with initial speed 17.0 m/s. The object -kec3ho,f,wd ’s speed 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 final speed of the object?

  16.40: An object moves in a circle, starting bnetp-i(z- we x94j: bat the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved c :eew(-jb 9t n-bz4ixpounterclockwise 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 buc qtk3yg(n,pi /ket 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 t(q 3tygik n/p,he 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.