Inertia
Is the propensity of a body, or more correctly its "mass," to resist a force which tends to change either its state of rest or, alternatively, its state of motion. It is the inertia of the flywheel which carries it round against the resistance of the compressed charge. It is the inertia of the car which resists the effort of the brakes pulling it up.
Inlet Pipe and Valve.--The inlet or induction pipe is the pipe connecting the carburettor to the engine, and provides the path for the vapour which passes through the inlet valve, as soon as this is opened, into the cylinder.