Optics Question 789
Question: A plane mirror is kept parallel to y-axis. A point object is approaching the mirror with velocity $ \vec{u}=(10\hat{i}+10\hat{j})m/s. $ The magnitude of relative velocity of objective w.r.t image is equal to
Options:
A) $ 20\sqrt{2}m/s $
B) $ 20m/s $
C) $ 10\sqrt{2}m/s $
D) $ 10m/s $
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Answer:
Correct Answer: B
Solution:
[b] Velocity of image in mirror
$ \vec{v}=-10\hat{i}+10\hat{j}\text{ }$
${{\vec{v}} _{rel}}=\vec{u}-\vec{v}=20\hat{i}. $
