a radar wave has a frequency of `7.8 xx 10^(9) s^(-I)`. The reflected wave from an aeroplane shows a frequency shows a frequency difference of `2.7 xx 10^(3)` `s^(-1)` on the higher side. Deduce the velocity of the aeroplane in the line of sight.

Explanation

To solve the problem, we need to determine the velocity of the aeroplane based on the frequency difference observed in the reflected radar wave. Here’s the step-by-step solution:

### Step 1: Identify the Given Values
- Frequency of the radar wave (f) = \(7.8 \times 10^9 \, \text{s}^{-1}\)
- Frequency difference (Δf) = \(2.7 \times 10^3 \, \text{s}^{-1}\)

### Step 2: Understand the Concept of Doppler Effect
When a wave source (in this case, the radar) moves relative to an observer (the aeroplane), the frequency of the wave changes. The frequency of the reflected wave is higher when the source is approaching the observer.
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