95.02: An object shown in the au2t9.a*na)m ffh jk8 hk+(kebs;:g qbm,frx4ccompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the instant shown?.hjkb kh4n+s r x a u*mq; g89,)(eaftbm2k:ff

  05.31: A child is belted into a Ferris Wheel seat that rotates counki,u(s7h,c x qterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the chil7ciqk(,uh,sx d by the seat and belt?

  08.14: A particle contz*qfp.u bbett1 -i+k/inuously moves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval di.e fq1uk/b *t- bz+pturing 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 path at cons;/ hx; k+m0td(w9y9zb5kxw rctvd: q vtant speed in a counter- clockwise direction. Consider axhw;9bkx0 9q+ c;t/vtkrdd zwvy:m(5 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 witgby 7 3kyvl t+jk4gm hcum,c;3zh.(h-h constant speed around the vertical circle shown. Which arrow best indicates hl ;h4c g k3myuczg3-,jv7b (tkmhy+.the direction 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 counterclm xk*gfqye))0 ockwise in a horizontal circle am0g)k*f) xeq ybove 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 let go of the string?

  15.23: A car moves with cons6/ v6jf-dg2c fdle0 v+wh0l febjl m45tant speed around a horseshoe-shaped path as shown with the arrows in the figure. Which one of the flvvhwl+0j/54jmed-6d 2fl0 6bc ffg eollowing choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts onx5538h+uml ulm-ecg dgygtc r0*mk39ni s);j the Moon perform an experiment with a simple pendulum that is released frisrlcg5u) x+m3mgu0m5 ntl jk;83yd9 cge h*- om the horizontal 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-like object rests c:aa) emxw *t4w rpgg46j,4/sr/vnrl2.0m from the center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5.0svgr j,p /lga6nrcm:erw*)x 44tw 4a/ 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 necessary to ;4xn b0 t(y8q*,ugz;pwhv p u2izc7gxkeep a 1. 0 kg puck moving in a circle of radius 0.5 m on a qcx(zu hyxt*buz2p, wi; 8;4g 07pvgnhorizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an 44e fb8t e(rcvvnk 0h6object (mass = 50 g) on the end of an 80-cm string rotating at a constant ratehkfbv4nr4c860 t(v ee of 4 times a second?

  09.24: A point mass moves along a hor z,2 ow9buuzm)izontal circular path of radius 0.8m with a constomz b,uu2 wz9)ant kinetic energy 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 a 0 er ns.9;y7;ahxqdfottached 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 the ball during eachx9y ;os e0;rd7fahq.n revolution is:

  99.22: A child whirls a ball at the end of a roptra4nde41oqp v8lqs m5 :+p z7e, in a uniform circular motion. Which of the following sd741l ev npt8qa rz54pso:q+ mtatements is NOT true?

  00.19: An astronaut in an orbiting space ca dh 2wmpz5t +hu6f3i(raft 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, rt6whu am d+i5fp2zh(3adius, and speed were all to double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward untilr 5 4h-tearocx/-y*jc the string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is re/ crj4hryet* a 5--xocleased 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 on a road in hilly terrain, wx cq(vxf (fi 9xl0hk/lr;yx,q -xg;0see figure to the right. Assume the car has speed v;;v9i xlxx0wqxkfgr(lq, cxh (0f/y- and the tops and bottoms of the hills have radius of curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.0 m/s. A:y;t,v ti x0ytt 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 magnitude of the upward f:;0t,y xytt viorce exerted by the road on the car?

  97.13: A small sphere is moving in a verti9uui2ikk q un39wox.lqin0 :v:ih1 (pcal circle at constant speed. The magnitu.091 (upnxn kv uoqliiiw2h3iqu : k9:de of the net force on the sphere

  11.47: A simple pendulum of length i5 )bhe+ h)osiLhasa 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 one) i+si 5o)hhb 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 simple exrhaf8;50. r ti7lsmpendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly r85;li. rmes0 ra h7xtfanks 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 c1+vumin/yy4 fa87yk force of 5.0 newtons is applied to a rubber stopper moving at a constant speed in a horiz1 u fma+7cy/kyi n8v4yontal 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 re e-b vlis+uh)j *f67kke0b-np st on 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. Thee*uh6lbk- +0)j-sb pkv7 fni e 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 c7vx4r blyt1)rxgq3j99 dj9e 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 99j9q bgve l73jx 4crxr1 td)ycircle?

  14.23:Two small identical coinr:vxj6ya3+b ps (labeled 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 coins from the cenrj+: 3xabp y6vter 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 and8/ cyfhdtw /,mai 01lw 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 mdifm01 /,/yalcw 8wt h and forms an angle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is i.c(vkfw*5yxk )lst y-n uniform circular motion as shown in the figure. The string to which the 5xvk )f-lc* stkwyy(.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 rest3o8 9ufebgc8b 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about i893 ebuco8fgbts 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 /3zpc 0.2/s6v -gt*wln auyi7olfm ceattached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating frmnlfi csag0eoy*7v/p.6c z3/t -ul 2wom 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 too9f y pyj4,m3gp, with initial speed 17.0 m/s. The object’s speed increases unif9ojypg3 mf ,y4ormly 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 at the g3xy 3 rpslf- yk.cerx c-1.i+4 (ghcztop, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an yl..4 cripcek +g3gxfr-y-(cx3 h1sz 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 bucw/ 26i2mhtkcx2 nl g.tn 2xxm0ket. 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 fa 2mkt2ginc. m2x2wxl6xt0/n hst 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.