Final answer:
Rockets can travel in outer space because they rely on the principle of thrust and the expulsion of exhaust gases, not on pushing against air. Outer space has no air, so there is less air friction compared to Earth's atmosphere.
Step-by-step explanation:
In the early days of rocketry, some people believed that rockets couldn't fly in outer space because there was no air for the rockets to push against.
However, this belief is incorrect.
Rockets are actually more efficient in outer space than in Earth's atmosphere.
When a rocket is in Earth's atmosphere, the air does not provide thrust for the rocket.
Instead, the rocket's engines expel exhaust gases at high velocity, creating a large backward force on the gas, which in turn exerts a large reaction force forward on the rocket called thrust.
While the air in Earth's atmosphere can create air friction, outer space has no air, resulting in less air friction.
Therefore, rockets can travel in space because they do not rely on pushing against air for propulsion. Instead, they rely on the principle of thrust and the expulsion of exhaust gases.
This allows them to accelerate and travel in the vacuum of space.