Which of these is a tool used in software development?

How can you increase the strength of an electromagnet?

Two carts, one of mass 2m and one of mass m, approach each other with the same speed, v. when the carts collide, they hook together. assume that positive momentum is to the right. which graph best represents the momentum of both carts over time, before and after the collision?

This is the number of complete movements of a wave per second.