Concave Lens and Convex Lenses | Kunal AcademyScience
Concave Lens and Convex Lens Concave Lens: A concave lens is a lens that is thinner in the center and...
Why Welding Light Harms the Eyes? | Kunal AcademyScience
Why Welding Light Harms the Eyes When welding, intense light is produced by the electric arc formed between the...