# Momentum

Kelsie C.

Momentum is the quantity of motion of a moving body, measured as a product of its mass and velocity. The law of conservation of momentum tells us that you can't just lose momentum - it has to go somewhere. The formula for momentum is p=mv, where p is momentum, m is mass in kg, and v is velocity in m/s. P represents momentum because the word "impetus" formally in place of "momentum" comes from the latin, "petere," to go towards or rush upon. A heavy moving van and a motorcycle could have the same momentum if the motorcycle is going fast and the van is going slow. If the van weighs ten times as much as the motorcycle, and is driving 5 mph it would have the same momentum as the motorcycle driving 50 mph. In an **elastic collision **no kinetic energy is lost. All of that energy is still in the object, so we say that energy was conserved. In an **inelastic collision**, some of the energy will be lost to heat or sound or light or some other energy. The thing to remember is that the total energy didn't change, but some of it escaped into the air, ground, etc. Throwing a piece of clay to the ground would be an example of an inelastic collision, because the clay would be losing momentum to heat energy and sound engery. Angular momentum is the quantity of rotation of a body, which is the product of its moment of inertia and its angular velocity. Angular momentum happens in space all the time because in space, nebulae, stars, black holes, and plantes all have angular momentum, and they all spin around. #momentum #kettner #tackk