Why doesn't the math add up?
(media.greatawakening.win)
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The force that makes a rocket go up has nothing to do with the exhaust pushing against air. Newton's Third Law of Motion: Any force applied to an object will be subjected to an equal and opposite force from the object.
Chemical combustion in the engine creates an outward force and pressure that must escape through a nozzle. The engine itself is fixed, so that forward force is transferred to the rocket body. If the force is enough to overcome inertia, the rocket accelerates (First Law). How much force depends on the mass of the combustion products and the speed at which they travel (Second Law).
It's like firing a rifle. It has recoil, whether your shoulder is there to push against or not. That recoil is the sum total of the force expended pushing the bullet forward. Small bullet, big velocity. Big human, small velocity.
In a rocket, though, the bullets are much smaller (molecules) but there are trillions per second and traveling nearly 100,000 MPH leaving the nozzle.
Best explanation I've ever had, thanks! Molecules as trillions of bullets is a great vizualization.