A man of height meters is moving from a lamp post at the rate of . If the height of the lamp post is metres, then the rate at which the shadow of the man is lengthening is
Explanation for the correct option:
Step 1. Finding the rate at which the shadow of the man is lengthening:
Let PQ be the man and AB be the Lamp post. Let CQ be the shadow.
Since, the man is moving from a lamp post at the rate of . Therefore,
According to the figure,
Step 2. Differentiate it with respect to
Required rate of length of shadow is
Hence, the correct answer is option B