what propels a rocket away from the surface of the earth?
the only force acting on the rocket in the time its in the air is gravity. so the force acting against it (the force that propels it) is the force coming out of the rocket's exhaust which is greater than gravity.
lift.
The propulsion system of a rocket is what propels it away from the surface of the Earth. The most common type of propulsion used in rockets is called "rocket propulsion." It works on the principle of Newton's third law of motion, which states that for every action, there is an equal and opposite reaction.
In a rocket, the propulsion system typically consists of a rocket engine, which generates and expels high-speed exhaust gases. These gases are expelled in a controlled manner through a nozzle at the rear of the rocket. As the gases are expelled at high speeds, the rocket experiences a reactionary force in the opposite direction, propelling it forward.
To understand how a rocket engine generates this force, we need to look at its basic operation. Most rocket engines utilize a combination of a fuel (such as liquid or solid rocket propellant) and an oxidizer. When these components are ignited and burned within the rocket engine's combustion chamber, a large amount of hot gas is produced.
As the high-pressure gas expands and flows out of the rocket engine through the nozzle, it's directed in a specific direction, typically straight backward. According to Newton's third law, every action (the expulsion of exhaust gases) has an equal and opposite reaction, so the rocket experiences a thrust force pushing it forward.
It's important to note that rockets work not by pushing against the Earth's surface but by expelling gases with high velocity. This enables them to overcome the force of gravity and propel themselves away from the surface.