Diameter of eye ball is

Dark muscular diaphragm that controls the size of the pupil is

The ability of the eye lens to adjust its focal length is called

Myopia or short sightedness can be corrected using

An old person cannot see nearby objects clearly due to loss of power of accommodation of the eye, this condition is called

Path of light becomes visible when light enters a dark and dusty room through a small opening is termed as

.................. is least scattered colour, even by fog and smoke and can be seen as the same colour over a long distance

The human eye forms the image of an object at its

Change in focal length of an eye lens is caused by the action of the

Cylindrical lens is used to correct the defect in the case of

Eye defect at old age is called