Purpose:Compare the weights of one kilogram (SI unit of mass) to one pound (English system unit of force)
Description:This set of two brass masses (one lb and one kg) is suitable for passing around among the students, so they can get a hands-on feel for the difference between the units. This is valuable in introductory classes which may have students who have not encountered metric units, or whose introduction to them was only as an arithmetic exercise in making unit conversions. It is valuable for them to experience the masses themselves and begin to build a physical intuition for what they represent in terms of mass and force.