If you increase the frequency of a sound wave four times, what will happen to its speed? a. the speed will increase four times. b. the speed will decrease four times. c. the speed will remain the same. d. the speed will increase twice. e. the speed will decrease twice.

What is the function of the commutator in a dc motor? a. to spin the magnet b. to change direct current into alternating current c. to change alternating current into direct current d. to spin the wire coil

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?

What is an aquifer for science class