Hydrometer-Spring balance instrument

摘要

The Hydrometer-Spring Balance is a new instrument introduced by the authors in physics in order to simplify the manipulating of two instruments which are the Hydrometer that measure the density of the liquid and the spring balance that measure the mass of an object inside and outside the liquid. So the new instrument can be used instead of the two traditional instruments. The new instrument will be put in a graduated cylinder filled with water and this will facilitate the measurement of the volume of the displaced water that is equal to the volume of the object, so we can measure at the same time the mass of the object and its volume therefore we can deduce the density of the object with respect to the density of water. The new instrument allows us to measure also the density of other liquids such as alcohol, benzene, oil, milk, salt water, petroleum products... with respect to the density of the water.