When an object is kept at a distance of 30 cm from a concave mirror, the image is formed at a distance of 10 cm from the mirror. If the object is moved with a speed of 9 cms–1, the speed (in cms–1) with which image moves at that instant is ____.
Answer (integer)
1
Solution
V<sub>I</sub> = Velocity of image with respect to mirror<br><br>V<sub>0</sub> = Velocity of object with respect to mirror<br><br>$$|\overrightarrow {{V_I}}| = |- {{{v^2}} \over {{u^2}}}\overrightarrow {{V_0}} |$$<br><br>$= | - {{10 \times 10} \over {30 \times 30}} \times 9|$<br><br>$= 1$ cm/s
About this question
Subject: Physics · Chapter: Optics · Topic: Reflection and Mirrors
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