The focal length of the lens to be used to correct hypermetropia when the near point distance is “d” cm.

The ability of accommodation of the eye usually decreases with ageing. This type of defect in vision is called ………

A person suffering from myopia and hypermetropia uses ……… lens.

Presbyopia can be corrected by using ……… lens.

The degree of convergence or divergence of light rays that can be achieved by a lens is called ……………

The reciprocal of focal length of a lens is called ………………

The unit of power is …………

In case of eye defect called “myopia” image is formed …………

If a person uses a lens of -2.5 D power, then the focal length of the lens is …………

Find the focal length of the lens if the power of the lens is – 2D

A doctor advised to use 4D lens. The focal length of the lens is …………

If far point of a long sighted person is ‘x’. The focal length of the lens he has to use is …………

The minimum focal length of eye lens for the person of hypermetropia is greater than …………

A doctor has advised to use 2.5D lens. The focal length of the lens is …………

Ramu can read a book perfectly well but cannot read the writing on black board unless he sits on the front row in class. Name the defect he has …………