Pressure-fed engine (rocket)

Okay kiddo, so imagine you have a water gun that shoots water really far and really fast. But you need to get the water from the water tank to the nozzle so it can shoot out. One way to do this is to pump the water from the tank to the nozzle with your hand, right? But that's tiring and slow!

Now, imagine you had a bigger water gun that's like the size of a big truck and it shoots something much hotter and faster than water - like a rocket engine! You can't just pump the fuel (that's what we call the stuff that makes the rocket go) from the tank to the engine with your hand because that's too hard.

So people who make rockets figured out how to move the fuel from the tank to the engine more quickly and easily. They do this by using something called a pressure-fed engine.

A pressure-fed engine uses the pressure of the fuel in the tanks to move the fuel into the engine. They put gas (that's like air, but it makes the fuel go faster) inside the fuel tank to push it out of the tank and into the engine. It's like when you drink from a straw: when you suck the air out of the straw, the air pressure pushes the drink up into your mouth.

Since the rocket fuel is very heavy and thick, the gas has to be powerful enough to push the fuel into the engine. Once the fuel is inside the rocket engine, it gets ignited (that's like lighting a match) and blasts out of the back of the rocket to create a big fire that pushes the rocket up into space!

So that's a pressure-fed engine! It's a bit like using a straw to drink your juice, but for rockets instead!