Which defect of vision can be rectified: (a) By using a concave lens? (b) By using a convex lens?
(a) Myopia(b) Hypermetropia
Name one of the common defects of vision and the type of lens used to remove it.
Myopia is the defect of vision that is removed by using a concave lens.
The human eye possesses the power of accommodation. This is the power to: (a) alter the diameter of the pupil as the intensity of light changes (b) distinguish between lights of different colours (c) focus on objects at different distances (d) decide which of the two objects is closer
(c) focus on objects at different distances
The term “accommodation” as applied to the eye, refers to its ability to: (a) control the light intensity falling on the retina. (b) erect the inverted image formed on the retina. (c) vary the focal length of the lens. (d) vary the distance between the lens and retina.
(c) vary the focal length of the lens.
To focus the image of a nearby object on the retina of an eye: (a) the distance between eye-lens and retina is increased (b) the distance between eye-lens and retina is decreased (c) the thickness of eye-lens is decreased (d) the thickness of eye-lens is increased
(d) the thickness of eye-lens is increased