Final answer:
True, glazing in an engine cylinder occurs because of low combustion temperatures and pressures, which cause incomplete combustion and result in a varnish-like coating impairing engine performance.
Step-by-step explanation:
The statement that glazing occurs because of low combustion temperatures and pressures in the engine cylinder is True. Glazing refers to a condition where combustion byproducts, unburned fuel, and oil additives create a varnish-like coating on the cylinder walls and piston rings. This typically happens due to insufficient heat and pressure within the combustion chamber which does not allow for complete burning of the fuel-air mixture. Incomplete combustion can lead to deposits that form a glazed surface, impairing the engine's performance and reducing efficiency.
An internal combustion engine is characterized by both thermal and mechanical events; it begins with a thermal action where ignition of the fuel-air mixture causes an increase in temperature and consequently pressure, as described by the ideal gas law. In an ideally running engine, this reaction is sharp and allows pressure to push the piston, performing work. However, at low combustion temperatures followed by insufficient pressure, the efficiency of this process reduces, potentially leading to glazing.