NEET Physics Waves Questions Solved

The intensity level due to two waves of the same frequency in a given medium are 1 bel and 5 bel. Then the ratio of amplitudes is

(1) 1 : 4

(2) 1 : 2

(3) 1 : 10⁴

(4) 1 : 10²

(4) By using $L = \log_{10} \frac{I}{I_{0}}$

$L_{2} - L_{1} = \log_{10} \frac{I_{2}}{I_{0}} - \log_{10} \frac{I_{1}}{I_{0}}$

$5 - 1 = \log_{10} \frac{I_{2}}{I_{1}}$ ⇒ $4 = \log_{10} \frac{I_{2}}{I_{1}}$ ⇒ $\frac{I_{2}}{I_{1}} = 10^{4}$

⇒ $\frac{a_{2}^{2}}{a_{1}^{2}} = 10^{4}$ ⇒ $\frac{a_{2}}{a_{1}} = \frac{10^{2}}{1}$ ⇒ $\frac{a_{1}}{a_{2}} = \frac{1}{10^{2}}$

Difficulty Level:

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