Two technicians are discussing an engine with an interference design. Technician A says if a valve remains open when its cylinder reaches TDC, the piston may strike the valve. Technician B says if a valve remains open when its cylinder reaches TDC, valvetrain damage can result. Which technician is correct?

Both Technician A and B are right.

Explanation:

Both Technicians are correct. when a valve remains open as it approaches the TDC(top dead center), they piston may strike the valve which would result to damage of the engine. Same applies when it is open as it approaches the top dead center as a valve train damage may occur. As the driven train is responsible for providing power to the wheels from the engine block.

snell's law

refractve index = sin incidence / sin refraction