If the amplitude of waves at a distance `r` from line source is `A`. The amplitude at a distance `4r` will be

Options

A. `2A`
B. `A`
C. `A//2`
D. `A//4`

Explanation

To solve the problem of finding the amplitude of waves at a distance \(4r\) from a line source, given that the amplitude at a distance \(r\) is \(A\), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Relationship Between Amplitude and Distance**:
- The intensity of waves is proportional to the square of the amplitude (\(I \propto A^2\)).
- The intensity is also inversely proportional to the square of the distance from the source (\(I \propto \frac{1}{r^2}\)).
- Therefore, we can conclude that amplitude is inversely proportional to the distance from the source.
...