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Question
An instrument is able to detect the reflected waves from an enemy aeroplane, after a time interval of 0.02 milliseconds. If the velocity of the waves is 3 × 108 ms−1, calculate the distance of the plane from the radar.
Solution
The distance of the plane from the radar is
Distance = Velocity × Time
= 3 × 108 × 0.02 × 10−3 mmm
= 0.06 × 105 m = 6 × 103 m
= 6 kilometres.
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