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Mechanical Engineer & Masters in Technical Physics – Rockets Do Not Work in Space | Flat Earth Talk

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This will probably get me banned from this sub but I just want to explain in a detailed manner why this engineer is incorrect.
The only difference between throwing a pencil and a bowling ball while standing on a skateboard is the mass of the object being thrown. Static inertia is a thing. That engineer in the video is correct about that. If you throw the bowling ball while on the skateboard, the bowling ball’s static inertia will push you back with the same force you used to throw it and make you roll back at least a few inches. The pencil is the same. You throw the pencil and it pushes you back. However, the pencil’s mass is much smaller and therefore throwing it requires very little force but since very little force was used to throw the pencil and, as newton’s law states, every force as an **equal** and opposite reaction, very little force from the pencil will push you back. The amount of force from the pencil is too small for you to feel but does exist. Just because you can’t feel it does not mean it does not exist but if you try this yourself you will not move because the force is easily absorbed by the friction the skateboard has with the ground. But if you were on some special skateboard with wheels that have absolutely 0 friction with the ground, you will notice you will be moving backwards at a fraction of an inch per several hours.
Pushing a car while on a skateboard is the same as throwing a pencil on a skateboard. You push, you roll away while the car doesn’t because your mass is far less than that of the car just like the pencil’s mass is far less than yours and flies away while you don’t and if the car is on a frictionless surface, it will slowly drift away after you push it just like you did when you threw the pencil while on the frictionless skateboard.
When throwing something or pushing something while on a skateboard, the force was only applied while you had your hands on it and you stop applying force once you are no longer touching the object and start to drift away. Now what if you were not on a skateboard? When you have your feet on the ground, the friction you have with the ground is immense and prevents you from moving back just like friction kept you from moving back when you threw the pencil until you stood on the frictionless skateboard. When you run, you push the ground using the friction your feet have with it and it pushes you back and you can do this as many times as you want as long as you can run and have friction with the ground. Pushing a car is the same as simply running. It takes longer because of the increased mass but despite you weighing a lot less than the car, the car is on wheels and you are not so you can push it as fast as you can run if you keep pushing it for long enough.
This engineer here thinks rockets use the air as the ground and the jet of burning gasses coming out of the rocket as legs to push the ground. That’s not how rockets work. A rocket is like you standing on a skateboard and the fuel is like a backpack on your back that is full of bowling balls or pencils and you accelerate by throwing each bowling ball/pencil one at a time until your backpack is empty.
Do rockets being able to work in space prove that space exists? No it does not. It just means we can explore it if it is proven to in fact exist but proving if space is either real or fake is a whole other story that I currently don’t feel like talking about after writing all of this.