Scleral lenses have gained popularity in the last decade. From a lens with limited viability for over 100 years to the fastest growing segment of the gas permeable lens market, scleral lenses have come a long way.
Mass and Weight. The mass of an object is a fundamental property of the object; a numerical measure of its inertia; a fundamental measure of the amount of matter in the object. Definitions of mass often seem circular because it is such a fundamental quantity that it is hard to define in terms of something else.
Mass is the measure of inertia that an object has. Contrary to popular belief, mass and weight are two different terms. Weight refers to the net gravitational force exerted onâ¦ an object, with an SI unit of Newtons, while mass refers to the ability of the object to resist changes in velocity, or acceleration.