Although dark matter is a very abstract subject some of the basic concepts are based on evidence that can be explained very well by experimental demonstrations. Wanting to approach this complex subject we chose to conduct a simple experiment using the centripetal force apparatus in circular motion with the aim of relating the speed of an object moving in a circular orbit to the mass of the object around which they are rotating. Then using the law of universal gravitation, Newton’s 2nd law of motion and the centripetal acceleration equation students will derive the mathematical relationship by which they can calculate the mass of the sun using planetary orbits.