Collisions and conservation laws
This free course, Collisions and conservation laws, is about collisions and how they may be understood using concepts referred to as the conservation of linear momentum and the conservation of kinetic energy. We’ll begin by defining some important quantities that will be used in what follows. A collision is a brief, but often powerful, interaction between two bodies in close proximity; we often idealise the situation in physics problems to consider collisions of pointlike objects travelling along a line or in a plane. Linear momentum is a physical property of a body in motion which is equivalent to its mass multiplied by its velocity. It is a vector quantity so possesses both a magnitude and a direction, which is the same as the direction of the body’s velocity. The kinetic energy of a body is a measure of the energy it possesses by virtue of its motion. It is a scalar quantity, possessing a magnitude only, which is equivalent to half the body’s mass multiplied by the square of its speed.
This OpenLearn course is an adapted extract from the Open University course.