So, from what I understand, Newton’s third law says that for every action, there is an equal and opposite reaction.
I’m having a very hard time wrapping my head around it, as it seems as though if his law worked the way I interprete it to, pushing an object or denting an object would be impossible.
For example,
If someone were to push a book on a table, the force they applied on the book to push it, should be countered by an equal and opposite reaction force, therefore not allowing them to move the book.
In another example, if someone were to push a piece of metal, there should be an equal and opposite reaction force (normal contact force?) which would not allow the person to move the metal (can’t dent it), no matter how much force they use.
I guess what I would like to know would be why this is not the case in the two above examples, and what is it that I am not interpreting correctly with Newton’s third law.
Thank you!!
In: Physics
The forces are the same, but the movement also depends on the mass of the objects. So you push a book with some force, the book is light so it will accelerate in the direction you move it. The book pushes you with exactly same force, but you are much heavier so you accelerate at much smaller rate and barely move. Also you’re countering the acceleration with your body. In space you wouldn’t be able to do it and you would really move (still much slower than the book).
Less ELI5: the formula for acceleration is a = F/m where F is the force (equal for you and the book) and m is the mass (different for each). So you can see that with same force you get different results for you and the book.
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