Definition check — simple steam engine: Is the statement correct? “If steam expands in a single cylinder and then exhausts to atmosphere or to a condenser, the engine is called a simple steam engine.”

Introduction:
Engine taxonomy distinguishes between simple (single-expansion) and compound (multi-expansion) machines. The definition does not depend on whether the exhaust discharges to atmosphere or to a condenser; it hinges on how many cylinders perform the expansion work.

Given Data / Assumptions:

• Single expansion stage in one cylinder.
• Exhaust may be non-condensing (to atmosphere) or condensing (to vacuum).

Concept / Approach:
A simple steam engine completes the entire steam expansion in one cylinder. A compound or multiple-expansion engine distributes expansion over two or more cylinders. The presence of a condenser merely changes back pressure and efficiency; it does not change the “simple” classification if expansion still occurs in a single cylinder.

Step-by-Step Solution:

Verification / Alternative check:
Classic texts list “simple non-condensing” and “simple condensing” as two subtypes within the simple engine category.

Why Other Options Are Wrong:

• Incorrect: conflicts with standard classification.
• “Only if non-condensing/condensing”: exhaust destination does not define “simple.”
• “Only with throttling”: governor method is independent of the simple/compound distinction.

Common Pitfalls:
Equating condenser presence with compounding; the condenser affects back pressure, not expansion staging.

Final Answer: