The cause of change in momentum is: change in inertia impulse change in force energy

Which one of the following research methods can show cause and effect

How do the kidneys affect homeostasis

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.