The point where parallel rays of light converge or appear to diverge is significant because it represents the principal focus of the lens. Understanding the behavior of light at the principal focus is crucial for various optical applications, such as ...

Parallel rays of light incident on a concave lens are refracted in such a way that they appear to diverge from a point on the principal axis. This virtual point is also called the principal focus, but in this case, ...

Parallel rays of light incident on a convex lens are refracted and converge to a point on the principal axis. This point is known as the principal focus of the lens.

The principal focus of a lens is the point on the principal axis where parallel rays of light, after passing through the lens, converge or appear to diverge from. For a convex lens, these rays converge to a point, while ...

The paper burns because the parallel rays of sunlight are converged by the lens to form a sharp and bright spot on the paper. This spot acts as a real image of the Sun, concentrating sunlight at that point and ...