Knocking in spark-ignition internal combustion engines is not the same as _______

pinking

pre-ignition

pinging

detonation

Correct Answer : pre-ignition

Explanation : Knocking and pre-ignition are two separate events. Knocking happens when the combustion of some of the air-fuel mixture doesn’t occur because of the propagation of flame front due to spark-plug ignition, but when one or more air-fuel mixture pockets explode outside the normal combustion front. Pre-ignition refers to the case in which combustion happens even before the spark-plug fires.

Recently Updated in Rocket Propulsion Questions

1-methyl-1, 2-dicyclopropyl cyclopropane is also called as _______

RP-1

Jet fuel

Syntin

Kerosene

Correct Answer : Option (C) : Syntin

Explanation : Syntin is a high-energy formulation briefly used in the upper stages of rockets developed by the Soviet Union. Its molecular formula is C₁₀H₁₆ and it is a mixture of 4 stereoisomers.

The fuel which releases the most energy per unit mass of combustion is ______

RP-1

LH₂

Kerosene

Methane

Correct Answer : Option (B) : LH₂

Explaination : Compared to hydrocarbon fuels, liquid hydrogen delivers most energy per unit mass of combustion. Any hydrocarbon fuel, when subjected to combustion produces more pollution than LH₂.

Which of the following fuels were used in the first stage of Titan I?

RP-1

RDX

HMX

None of the above

Correct Answer : Option (A) : RP-1

Explanation : RP-1 fuel is used in the first stage of Titan 1. Other than that, it was also used in the first stages of Saturn V, Energeia, Saturn I and IB etc. It is a cheaper and less explosive alternative to LH₂.