what has more potential energy, a skateboarder on top of the a 20-foot ramp, for a skateboarder on top of a 5 foot ramp ?

10 newton object is placed 3 meters from the fulcrum. at what distance on the other side would you need to place a 15 newton object to balance the lever? show your work!

How to tell if a molecule is polar or nonpolar with electronegativity

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.