Multiple choice

1. A belt passes over a wheel of radius 32 cm. If a point on the belt has a speed of 6.25 m/s, how fast is the wheel turning? A. 172 rev/min C. 180 rev/min B. 177 rev/min D. 187 rev/min10. In Problem 9, how large a force must the wire exert on the bead when it is at point D? A. 2.3481 N C. 3.822 N B. 3.1659 N D. 4.6519 N2. A pulley of 8 cm radius, on a motor, is turning at 80 rev/s and slows down uniformly to 42 rev/s in 5 seconds. Calculate the acceleration and length of belt it winds in this time. A. - 44.7522 rad/s? and 145.3097 m B. - 45.7522 rad/s and 148.3097 m 80 - 502. 65 5 C. - 46.7522 rad/s? and 151.3097 m D. - 47.7522 rad/s and 153.3097 m 42: 263 - 894v .-u vuue: 3. A 500-9 object is tied to the end of a cord and whirled in a horizontal circle of radius 1.50 m at a constant 6 rev/s. Assume that the cord is horizontal, i.e., that gravity can be neglected. Determine the tension in the card. A. 0.9.734 KN C. 12783 KN 8. 1.0659 KN D. 1.5675 KN L The wheel on a grinder is a uniform BOD-g disk of lD-cm radius. it decelerated uniformly to rest from 1600 rpm in a time of 5 seconds. How large a friction torque slows its motion? Note: Torque is the product of Moment of inertia and Angular Acceleration. A. l.81.93 N-cm C. 1.9348 N-cm B. \".893 Ncm D. 1.3948 Ncm 5. A 70-kg woman stands on a light, cubical box that is 8 cm on each edge. The box sits on the floor. How much pressure or stress does the box exert on the floor? A. 107.1875 KPa C. 105.1877 KPa B. 108.1775 KPa D. 101.7875 KPa\"0"- - m :5. A box-shaped gelatin dessert has atop area of 25 cm' and a height of 3.8 cm. When a shearing force of 0.80 N is applied to the upper surface. the upper surface displaces 5 mm relative to the bottom surface. What is the shear modulus tor the gelatin? A. 1.8792 KPa C. 3,1173 KPa 8. 2.432 KPa D. 3.6512 KPa ENGOPRY 7. A solid cylindrical steel column is 8 meters long and 12 cm in diameter. What will be its decrease in length when carrying a load of 120,000 kg? Young's modulus = 2.5 x 10" Pa. A. 2.3879 mm C. 3.3274 mm B. 2.7613 mm D. 4.1278 mmQUIZ 4 8. A metal wire 85 cm long and 0.18 cm diameter stretches 0.0450 cm when a load of 12 kg is hung on its end. Find the Young's modulus for the material of the wire. A. 87.2929 GPa C. 102.3471 GPa B. 95.53341 GPa D. 109.4879 GPa. '', 9. As shown, a 30-9 bead slides from rest at A along a frictionless wire. If h is 75 cm and R is 10 cm, how large a force must the wire exert an the head when it is at Paint B? A. 2.46 N C. 2.72 N - B. 2.58 N D. 2.94 N