Question

how will you differentiate between a concave and a convex lens without touching them?​

Answer 1

Answer:

by testing the lenses

Explanation:

our mirrors are concave by that we can differant

Answer 2

We can differentiate between a convex and concave lens by seeing the image.

• On keeping the lens near a printed page, if letters appear magnified, the lens is convex and if the letters appear diminished, the lens is concave.
• On seeing a distant object through the lens, if its inverted image is seen, the lens is convex and if an upright image is seen, the lens is concave.