Write down the names of the specified parts of the human eye.

i) Dark muscular diaphragm that controls the pupil.

ii) The screen where the image is formed by the eye lens.

In traffic signals _________ colour light is used to stop vehicles because it has ______wave length. (Hint: scattering of light is inversely proportional to the fourth power of its wavelength)

Fill the table with the appropriate words given in bracket.

(Convex mirror, Plano convex, concave mirror, Plane mirror, convex lens, Concavelens)

You know that myopia is a common refractive defect of vision. A person with this defect can clearly see only objects that are near. Using concave lens of suitable power this defect is corrected.

i) Mention the other two types of defects.

ii) Explain how they can be corrected.

i) Which of the compass needle orientations in the following diagram correctly describesthe magnet’s field at that point?