One of the most amazing feats that humans have accomplished is
going into space. This video from NASA shows a rocket taking
off:
How does a rocket take off?
Rockets need to escape the Earth's gravity - the force pulling
objects towards the Earth. To do this, they must generate a huge
amount of thrust - the force that pushes the rocket upwards.
Rockets carry a lot of fuel. This fuel burns slowly and
generates lots and lots of heat. When the rocket fuel burns, it
also produces gas. The build up of this gas escapes the rocket with
a lot of force and provides enough thrust for the rocket to blast
off.
Rocket burning fuel to provide
thrust for take off
To maintain enough thrust to overcome the Earth's gravity, the
rocket must carry lots of fuel in many tanks. When a tank of fuel
is used up, the fuel tank is released from the rocket, which makes
the rocket much lighter.
In summary:
Rockets take off by burning fuel.
Burning fuel produces gas as a byproduct, which escapes the
rocket with a lot of force.
The force of the gas escaping provides enough thrust to power
the rocket upwards and escape the the force of gravity pulling it
back to Earth. Simple!
You can make your own rocket HERE - it's
powered on Alka-Seltzer, not rocket fuel!