Question

how can you diffetentiate a convex and concave lens without touchong them​

Answer 1

Explanation:

Light - Reflection and Refraction. How will you distinguish between a convex and a concave lens without touching them? Convex and concave lens can be distinguished by touching them. If the curved surface is bulging outwards then it's convex lens and if the curved surface is curved inwards then it's concave lens.

Answer 2

Convex lens converges the incident light where as concave lens diverges the incident light so by the effect on ray of light after falling