An object's ability to do work is measured by its mechanical energy, or the sum the object's kinetic energy and potential energy. Mechanical energy is due to the position or movement of an object. The formula for mechanical energy is mechanical energy = kinetic energy + potential energy.
Mechanical energy, mechanical energy is the energy due to the position or movement of an object okay. And ther are 2 big forms of mechanical energy, kinetic energy and potential energy. So let's look at some examples I've got my scush ball and if I hold it up high it's got potential energy right? I can let go of it and what happens? Well that potential energy is getting converted into kinetic energy right. Right down here when it hits the floor it has no potential energy and I've stopped the kinetic energy right so again those types of energy are transferable and you'll often see a lot of problems where you've got to convert something from a certain amount of kinetic energy to potential energy let's say with a pendulum that's moving where it has a maximum amount of kinetic energy and then that kinetic energy is slowly converted into potential energy. So let's look quickly at what kinetic and potential energy is. So kinetic energy which is the energy of movement equals one half times the mass of the object times the velocity squared. So one half mv squared is the formula we use for kinetic energy.
Potential energy when we're talking about positional energy, we need to know the mass and then the force of gravity g and then the height we're moving it up. So mass times gravity times height gives us potential energy and remember gravity is 9.8 meters per seconds squared the force acceleration there. Okay so these are 2 types of mechanical energy and often times we'll be solving something from a certain amount of potential energy and figure out how much kinetic energy it has at its lowest point and we again use these 2 equations to solve problems with mechanical energy.