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Question
The guru of a yogi lives in a Himalyan cave, 1000 km away from the house of the yogi. The yogi claims that whenever he thinks about his guru, the guru immediately knows about it. Calculate the minimum possible time interval between the yogi thinking about the guru and the guru knowing about it.
Solution
Given:- Distance between the house of the yogi and his guru, s = 1000 km = 106 m
So, for the minimum possible time interval, the velocity should be maximum. We know that maximum velocity can be that of light, i.e. v = 3 × 108 m/s.
We know,
\[\text{Time, t} = \frac{\text{Distance}}{\text{Speed}}\]
\[ = \frac{{10}^6}{3 \times {10}^8} = \frac{1}{300} s\]
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