Question

the power of lens is -40d what is focal length​

Answer 1

Explanation: I hope this helps you please mark as brainliest answer

The reciprocal of the focal length of a lens in metres is called the power of the lens. The capacity of a lens to bend the rays of light depends upon the focal length. The smaller the focal length, the greater is the bending of a ray of light and vice- versa.

Answer 2

focal length =1/power

here,

power=-40

so, f=1/-40

→f=-2.5cm

so, focal length is -2.5 cm