An enemy plane is at a distance of 300 km from a radar. In how much time the radar will be able to detect the plane ? Take velocity of radio waves as `3xx10^(8)ms^(-1)`.

Explanation

Given velocity ( speed) `= 3 xx 10^ 8 m//s `
Distance , `(d) = 300 km = 300 xx 1000m`
total distance `= 2d = 2 xx 300 xx 1000 m`
time ` = (" total distance " ) /("Speed) = ( 2 xx 300 xx 1000 ) / ( 3xx 10^8 ) s= 0.002 = 2 ` millisecond