At some point of our lives, we would have all been in a plane, but how does a plane which weighs so much, stay in the air?
There are 4 basic force which act on all planes and rockets, essentially anything that wants to fly.
Lift, weight, drag and thrust.
Lift and weight act opposite to each other, while weight drags you down, lift allows you to go higher. So if lift is greater than weight we can go vertical up.
Drag and Thrust. Drag want to keep you back, while thrust wants you to go forward. The more thrust you have the further forward you will go.
Weight is the force of gravity acting in a downward direction. In planes, the bigger the plan the more it weighs. This means it requires more thrust than smaller planes.
Lift is the force that acts at a right angle plane. Meaning it pushes you straight up. In planes lift is generated by the shape of the wings.
In a plane lift is proportional to the square of the velocity. Put simply the faster you go the higher you get.
As a plane moves forward, its lift force increases until its equals or is greater than its weight.
Thrust is the force which propels the flying object in the direction of motion. In jets the engine provides thrust.
Drag is the force which acts in the opposition direction to thrust. This is caused by friction and difference in air pressure. If you put your hand outside a moving car you will notice your hand being pushed back. Your hand is creating drag.
These are the same forces when you drive a car. Notice, when the parachutes deploy the drag force is much greater than the thrust force.
When it comes to rockets, the forces acting on it are different.
