Paper Details

A block with mass m = 5.00 kg slides down a surface inclined 36.90 to the horizontal (Fig. 10.55). The coefficient of kinetic friction is 0.25. A string attached to the block is wrapped around a flywheel on a fixed axis at O. The flywheel has mass 25.0 kg and moment of inertia 0.500 kg ? m2 with respect to the n axis of rotation. The string pulls without slipping at a perpendicular distance of 0.200 m from that axis.

(a) What is the acceleration of the block down the plane?

(b) What is the tension in the string?

A spark-ignition engine has a compression ratio of 8, an isentropic compression efficiency of 85 percent, and an isentropic expansion efficiency of 95 percent. At the beginning of the compression, the air in the cylinder is at 13 psia and 60oF. The maximum gas temperature is found to be 2300oF by measurement. Determine the heat supplied per unit mass, the thermal efficiency, and the mean effective pressure of this engine when modeled with the Otto cycle. Use constant specific heats at room temperature.