Geometrical OpticsHard
Question
A point source of light is placed on the principle axis between F and 2F of a concave lens. On the other side very far, a screen is placed perpendicular to principle axis. As the screen is brought close towards lens
Options
A.The light intensity on screen continuously decreases
B.the light intensity on screen continuously increase
C.the light intensity on screen first decreases, then decreases
D.the light intensity on screen first decreases, then increase
Solution
Concave lens behaves as divergent lens and diverges the beam of light as passes from lens. When the screen is brought close towards lens it receive more number of rays hence light intensity increases.
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