Focal length is the distance between the center of a convex lens or a concave mirror and the focal point of the lens or mirror — the point where parallel rays of light meet, or converge
The focal length of an optical system is a measure of how strongly the system converges or diverges light; it is the inverse of the system’s optical power. A positive focal length indicates that a system converges light, while a negative focal length indicates that the system diverges light.
Deepti29
Focal length is the distance between the center of a convex lens or a concave mirror and the focal point of the lens or mirror — the point where parallel rays of light meet, or converge
Abhinav.arjun47
The focal length of an optical system is a measure of how strongly the system converges or diverges light; it is the inverse of the system’s optical power. A positive focal length indicates that a system converges light, while a negative focal length indicates that the system diverges light.