The Teaching of Optics

Abstract

OPTICS and mechanics are twin Cinderellas in the teaching of elementary physics. The beginner finds with growing disappointment that each covers ground remote from those thrilling matters of real life that they promised to deal with-remote from engines and machinery and from real optical instruments such as telescopes and microscopes. To make matters worse, a confusing fight rages round the teaching of each: a battle of units in mechanics, in which the mass and the weight of the projectiles employed seem inextricably mixed, and a battle of signs in optics, with l/v – l/u = l/f and l/v + llu = I/f as its war cries. Mechanics has been rescued by the toy manufacturers—if we may call admirable constructional apparatus such as ‘Meccano’ toys- and the mathematical studies of mechanics which seem so artificial if attacked too early are left until the later school stages when they can bring a real delight unspoiled by disappointed hopes of romance.