In the concave reflector of a torch, the bulb is placed:(a) between the pole and focus of reflector (b) at the focus of reflector(c) between focus and centre of curvature of reflector (d) at the centre of curvature of reflector
(b) At the focus of the reflector
Explanation
When a light bulb is placed at the focus of a concave mirror reflector, the diverging light rays of the bulb are collected by the reflector and then reflected, to produce a strong, parallel-sided beam of light.
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