(i) You have learnt that plane and convex mirrors produce virtual images of objects.
Can they produce real images under some circumstances? Explain.
(ii) A virtual image, we always say, cannot be caught on a screen. Yet when we see a virtual image, we are obviously bringing it on to the screen (i.e. the retina) of our eye. Is there a contradiction?
(iii) A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is?
(iv) Does the apparent depth of a tank of water change, if viewed obliquely? If so, does the apparent depth increase or decrease?
(i) Yes, plane and convex mirrors can produce the real
image, if the rays incident on the plane or convex mirror are converging to a point behind the mirror. A plane or convex mirror can produce a real image, if object is virtual.
(ii) No, there is no contradiction because virtual image
formed by the spherical mirror acts as virtual object for eye lens. Our eye lens is convergent and it forms a real image of virtual object on retina.
(iii) As, the fisherman is in air, the rays of light travels from rarer to denser medium, so they bend towards the normal. Therefore, the fisherman appears taller.
(iv) Yes, the apparent depth decreases, further when water
tank is viewed obliquely as compared to the depth when seen normally.