Question

How many dead centers are there in one cycle of a steam engine?
A. 4
B. 3
C. 2
D. 1

Answer 1

Hint: In a reciprocating engine, the dead centre is the position of a piston in which it is either farthest from, or nearest to, the crankshaft. The former is known as Top Dead Centre (TDC) while the latter is known as Bottom Dead Centre (BDC). Recall the construction and working of one of the types of the steam engine to answer this question.

Complete answer:
A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Let’s discuss the components of the steam engine in brief as follows.

The steam engine uses the fire to heat up the water in the boiler. When the water is heated, the ejecting steam from the boiler is pumped into the cylinder by the means of arrangement similar to the cycle pump. The machine that needs to be driven is connected to the piston. The motion of the cylinder is kind of in and out and therefore such engines are known as reciprocating engines.

The dead centre is the position of the piston at the top or bottom of the stroke. If the engine stops at the dead centre, we cannot start the engine from that position. There are two dead centers in one cycle of the steam engine:
-Top dead centre
-Bottom dead centre

Hence, option C is the correct answer.

Note: Remember that a reciprocating engine is the type of steam engine and it is the most inefficient steam engine. In the reciprocating engine, a piston moves up and down in a cylinder. The piston moves in four strokes creating intake, compression, power and exhaust strokes. These four strokes help in generating power.