# No. of revolutions the crankshaft has to complete in two-stroke engine to complete one thermodynamic cycle

## How many revolutions the crankshaft has to complete in two-stroke engine to complete one thermodynamic cycle?

Options:

a. half revolution of crankshaft
b. one revolution of crankshaft
c. two revolutions of crankshaft
d. four revolutions of crankshaft

Correct Answer: b. one revolution of crankshaft

Explanation:

The engine in which the power cycle is completed in two strokes of the piston is called as two-stroke engine. In the two-stroke engine intake and exhaust functions occur at the same time thus the starting of the compression stroke and the ending of combustion stroke happen simultaneously. Therefore for completing the one thermodynamic cycle (power cycle) the piston has to complete two strokes only those are one upward and downward movement. Thus the crankshaft completes only one revolution during the completion of power cycle. In four-stoke engine the piston has to complete four strokes to complete one power cycle.