The minimum temperature to which a Temperature substance must be heated without application of a flame or spark in order to cause that substance to ignite
is the premature ignition of the fuel produces an audible noise, which is called engine knockis the premature ignition of the fuel produces an audible noise, which is called engine knock
Ignition that t occurs when a substance in air, whether solid, liquid, or gaseous, is heated sufficiently to initiate or cause self-sustained combustion independently of the heat source