Which of the following statements for persons suffering from presbyopia is/are correct ? 1. They cannot distinguish colours. 2. It usually develops with ageing. 3. They wear either bi-focal lenses consisting of both concave and convex lenses or progressive lenses. Select the answer using the code given below :

Which of the following statements with regard to the phenomenon of the primary rainbow formation by water droplets is/are correct ? 1. It involves refraction and one internal reflection of sunlight.…

A person can see near objects clearly through his eyes but cannot see distant objects clearly. The possible reason(s) for this defect could be: 1. Excessive curvature of the eye lens. 2. The eye-ball…

With reference to street-lighting, how do sodium lamps differ from LED lamps? 1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps. 2. As street-lights, sodium lamps…

Which one of the following statement is not true for a person suffering from hypermetropia?

Which one of the following statements about the aperture of a convex lens is correct?