Why does a water not enter a submarine?

In order to control buoyancy, the submarine relies on special tanks that can be filled with water or air. To return to the surface, the tanks are filled with air. This makes the submarine denser than the surrounding water, which causes it to sink.

Were ww2 submarines air conditioned?

Actually heat was no problem in the South Pacific, but air conditioning was important, although it was a high user of energy. Even the electricians avoided fooling with that.

How much water does a water cannon shoot?

One water cannon, built in Germany, shoots a stream of water at up to 18 liters per second, enough to easily bowl over a person, writes Robert Booth at the Guardian. The power differs, too, with how far away the target is or how direct the hit is.

Do water cannons work to quell riots?

In several other spots around the world, authorities regularly use water cannons to quell riots. True water cannons are more than high-powered hoses run from a fire truck or hooked to a hydrant. Water cannons often are armored, too, to repel extra-dangerous crowds.

Can a cannon fire an explosive projectile?

A cannon does not have to fire an explosive projectile. Of course, they can, as shown by these 20mm explosive cannon shells. Note: This is partially in response to an answer saying that cannon shells were exploding whereas bullets were not. The difference between a bullet and a cannon shell lies solely in caliber.

What is the difference between a 20mm cannon and a bullet?

Many fighter planes are equipped with 20mm “cannons”. What is the difference between a “cannon” and a “gun”? , Amateur gun nut for 10+ years. Note: This is partially in response to an answer saying that cannon shells were exploding whereas bullets were not. The difference between a bullet and a cannon shell lies solely in caliber.