Question

what is the power of lens? write SI unit of power of lens and write the equation showing relation power of lens and focal length​

Answer 1

Answer:

Power of lens is known as the inverse of the focal length of the lens measured in meter(m). Power of lense = 1/ focal length in meter. The lense used is a convex lens because the focal length is a positive value.

Answer 2

The power of a lens is its ability to bend the light falling on it is called the power of the lens.

• The lens capability of the light falling on it to bend is termed as the power of a lens.
• This ability of a lens is completely dependent on its focal length.
• Dioptre is used as the international system of the unit for measuring the power of a lens.
• The relation between the focal length and the power of a lens is that power is the same as the reciprocal of the focal length.
• If the focal length is 1m then the lens power will be P = $\frac{1}{f}$.
• P = $\frac{1}{1}$, the power of the lens will be 1dioptre.