Newtons 3rd law says that an object exerts the same force back. Then why is it that if I push hard enough then the object will move? Is there a name for the total amount of force an object can put against me?
In: Physics
Newton’s third law is about the interaction between two objects
When you push on a box with a force of 100 Newtons, the box must push back with a force of 100 Newtons or your hand would be pushing through the box though the resistance from the box will always match the force on the box but it’ll be something under 100
Consider putting a weight on a big foam block, what happens? The foam squishes until it’s pushing up with as much force as the weight pushes down
As for why objects are able to move, newton’s third law only looks at the forces at the interface but you need to look at the forces on the object as a whole. There’s 100 newtons pushing the box to one side, if friction isn’t matching that then there’s a net force on the box and it will slide. At each interface (hand/box and floor/box) forces are equal and opposite, but the friction doesn’t have to match the hand force, they’re not the same action
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