a thin rod of length f/3 is placed along the optical axis of a concave mirror of focal length f such that its image which is real and elongated just touches the rod. calculate the magnification.
Asked by apurva151 | 14th Jun, 2015, 06:25: PM
Given that Rod, AB is placed along the optical axis.
The image of the rod will touch the rod, AB only when the end Cof the rod is placed at the centre of curvature of the concave mirror.
PC = 2f and CA = f/ 3
The image of the end C of the rod will be formed at C itself in this situation
At A side of the rod:
u = PA = PC - AC = 2f - (f/3) = 5f/3
Using the mirror formula, we get:
Answered by Yashvanti Jain | 15th Dec, 2017, 03:35: PM
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