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प्रश्न
A radar sends a signal to an aircraft at a distance of 30 km away and receives it back after 2 x 10-4 seconds. What is the speed of the signal?
उत्तर
Given t =2 x10-4
d = 30 km = 30 x 103 m
Speed of the signal = ?
Let ‘d’ be the distance of aircraft from the radar, then the total distance travelled by the wave in coming and going back = 2 d.
`"Velocity of wave, V"=("Total distance travelled, 2d")/"Time taken, t"`
`=(2xx30xx10^3)/(2xx10^-4)`
`=3xx10^8 `m/s
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