What happens to the vehicle mass ratio (Initial mass / Burnout mass) when the residual propellant is not available for combustion?

Increases rapidly

Decreases rapidly

Increases slightly

Decreases slightly

Correct Answer : Decreases slightly

Explanation : Residual propellant when not available for combustion is treated as inert mass. Since the inert mass increases, the burnout mass will also increase. The residual fuel amount is typically small. So the vehicle mass ratio (Initial mass / Burnout mass) will slightly decrease.

Recently Updated in Rocket Propulsion Questions

Which of the following is not a property of the main liquid oxygen valve?

Low pressure

High pressure

Cryogenic

Reusable ball valve

Correct Answer : Option (A) : Low pressure

Explanation : Main liquid oxygen valves are under high pressure. Since liquid oxygen easily evaporates under normal atmospheric conditions, they are kept in cryogenic tanks. These valves also make use of reusable ball valves.

German antiaircraft missile Wasserfall used four of which of the following valves?

Latch valves

Burst diaphragm

Isolation valves

Drainage valves

Correct Answer : Option (B) : Burst diaphragm

Explanation : Burst diaphragm is used in the German missile Wasserfall. It actually used 4 of such burst disks.

Which of the following valves help in controlling gas pressures?

Latch valves

Isolation valves

Burst diaphragm

Pressure regulator

Correct Answer : Option (D) : Pressure regulator

Explanation : Pressure regulator, as the name mentions, helps in regulating or controlling gas pressure. Other valves serve different purposes, like maintaining the flow until a pressure differential (burst diaphragm) or for isolation of a particular flow region.