What is the velocity of the MK 3A2 grenade underwater?

The correct choice refers to the MK 3A2 grenade's underwater velocity, which is reported to be 4,192 feet per second (FPS). This high velocity is significant because it showcases the grenade's design and intended use in delivering its explosive payload effectively even in underwater environments, where water density is notably greater than air. The ability of the grenade to maintain such a velocity allows it to achieve desired explosive effects while minimizing the risk of premature detonation or failure to detonate when submerged.

Understanding the context of underwater dynamics is crucial, as projectiles behave differently in water than in air. The velocity of a grenade under water is critical for tactical considerations, especially in operations involving naval forces or amphibious assaults. The precise measurement ensures that personnel can accurately predict the behavior of the grenade upon deployment in aquatic settings, thereby maximizing operational effectiveness.