In a tug of war, two teams exerts a force of 30 n each. what is the net force acting on the rope?

What determines the amount of inertia an object has

Consider a system to be two train cars traveling toward each other. what is the total momentum of the system before the train cars collide?   kg • what must the total momentum of the system be after the train cars collide?   kg •  

What happens when a rubber rod is rubbed with a piece of fur?