95.02: An object shown in the accompzi)vlhtoz 0(t n+4y-ianying figure moves in uniform circular motion. Which arrow best +nz4t zti yvi)lo-h(0depicts the net force acting on the object at the instant shown?

  05.31: A child is bet4;+mtnt*/8. p 9ydy zv c-v;tpeepw dlted into a Ferris Wheel seat that rotates counterclockwise at constant speed at/ 9vt e. ;t4zp 8 veyw-m+t*ptnyd;cpd an amusement park. At the location shown, which direction 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 constant speedphpn; 3f e0g4e(mbzd m/s/ka7 in a counter- clockwise direction. Consider a time interval es0zgdh;4 m p/ 7bne3amk(pf/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 circulp w i4t fnb(,w+xkb4p1ar path at constant speed in a counter- clockwise direction.ppw fx4bw 1ktb n4(,+i Consider 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 acceleration during this time interval?

  15.07: An object moves clockwise with constant speed a ucbk4n5h zx5 j/ gm4msz3zel ywv*)7,x 5tso6round the vertical circle shown. Which arrow best indicates the direction of/45tuz7,e ohy6bzzmws5vx s g5k mjl4nx)*3 c the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the / dwi7pfsbt((f 5g8ggc dd;0z:qm 8iwend 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 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 lef8 g b7i(m gpds ddq0i8;fz(c5t/ww :gt go of the string?

  15.23: A car moves with constant speed w,;bq;lt*5li b v7geeb5r4claround a horseshoe-shaped path as shown with the arro b lle ev,w qrcbl*b;5;t4i5g7ws in the figure. Which one 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 m,9vm e i1vvq/.hg *nuan experiment with a simple pendulum that is released from the horizovmn9. i*1,eqh vvgm/untal 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-lin:t-/kx2uuu-d et*u mke object rests 2.0m from the center of a rough turntable as the turntable rotates. The period of the turnuut k-:xu u/*n2-dmtetable'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 n yhggcikez 0r(d(p+ 01ecessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionlehgz (0depky1( ri c0g+ss surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 5bktk4 t zjx5uets+(9 00 g) on the end of an 80-cm string rotating at a constankk4b+ tt5eu 9jts 0(zxt rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path of radius 0.)+ied 0xmtqm4ru7kc- q :jxi+8m with a constant kinetic energy of 128J. What is the magnitude of the netqxk+t ) 4-m: rjd q0i7ix+uemc force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirledn 14ec-ui 4ujzyax p2:tp1 lj: in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the ball during each revo1ixnjl241 a:e-:typjp4u u zc lution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circular mkit37ny:3s9:eu(wln;tn wv tx 3 s8pl otion. Which of the following statements is NOT ts;u3 tk8s 3w(7:n n txytwp:lve3lin9 rue?

  00.19: An astronaut in an orbiting space craft attaches a mass m to a strin jprrf8mk dy;dr+9dl.. z(q.jg and whirls it around in uniform circular motion. The radius of the circle is r, kr9lrd p;.qdy+( jz.f. jd mr8the 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 which it is wtm55wkt0v;e attached makes a 90- degree angle with the vertical. The mass is released from rest and swingsvkett ;5 w05wm 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 travelt 7l .+zldcub 6fzv,d, l(c 6zw.;gegoing 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 tlztd(.bougv.;czw676+l l,zd,e cf g o feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant spee;ka9el9n(c , rx)d4fe jsapi5.x spr5d 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. Which one of the following choices best represents the male.5 9 n()a4rp9pc x,ej kd;sxr i5safgnitude of the upward force exerted by the road on the car?

  97.13: A small spherexecs lu9u vd.;lfwv ,d/7 4nc;m8xn+x is moving in a vertical circle at constant speed. The magnitude of the d; lc8u x/wxn,d lnufxs.v+4 ;vcm9e7 net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released from rest fx+lggnlm1c k9j xt(3u.z/ r x)rom 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 the mass. Which one of the following choices describes the rel+ 1 rggkx /uxm(l3j9tzn.xlc) ationship 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 dox fv2b/l- e4ev; 4gpsimple pendulum. The mass is released from fv;l2 p e obexd/-g4v4rest 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 through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to w8+tj 6 sw1difa rubber stopper moving at a constant speed i8 6i wf1dtws+jn 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 a vjb(lpu3yi-h/oc3otd i0iicf. m/5/n 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.d-bl5p3ii/fict0oy iu j3om/ cv/ (h 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 sd3 plk6md yw,)3zje*epeed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is at the lowest point of the circled ,j)pzwe6elykd3 *m 3?

  14.23:Two small identical coins (labeled X aeu+y r.-f/iwwndY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicularru-y e/iw. +wf 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 t62.hkvnp :p cp*vl u/the end of string and moves about the string’s fixed end in a conical motion witnhl2 6p*pt .:cv/pku vh 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 circular motion as shown in the figure. z,2,k -b x9hcu0n/t ip 6bmdnsThe string to which the mass is attached has a length o2uh snxmc0-pzb/nk ,6dit b9 ,f 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 fromngv2zray3- v(oe; hh * a horizontal disk’s center. The disk starts to rota;za3 o(e2-vrh g v*hnyte 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 atz g1x qvzz(..w m:ragzob61i)tached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk so :z1ziz 1zv6r ggmx.).a (qbwtarts 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, sto/*aq is yzsv* l,ks)(arting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclock/ a(ls*vq*isoz,y)ks wise 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, sto,ox 9;f 2tf:hr3n qxvarting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has mq v:;hx3n9of r ftx2,ooved 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 bucked:ih slcl7 5/vt 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 reh 7vls/i ld:5cmain 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.