Question

In four stroke cycle engines, an ample amount of ____________ is used during intake and exhaust processes.

(a) heat

(b) pressure

(c) power

(d) none of the mentioned

I had been asked this question in an internship interview.

Enquiry is from Total Engine Friction topic in portion Engine Friction and Lubrication of IC Engine

Answer 1

The correct answer is:

(b) pressure

In four-stroke cycle engines, pressure plays a significant role during the intake and exhaust processes. During intake, air (or air-fuel mixture) is drawn into the cylinder as the piston moves down, creating a vacuum. During exhaust, the piston moves up, and the exhaust gases are pushed out of the cylinder, creating pressure to expel the gases.