Statement I: If two people talk simulaneously and each creates an intensity of 60 dB at a point `P`, then total intensity level at the point P is 120 dB
Statement II: sound level is defined on a non-linear scale.

Options

A. (a)Statement I is true, Statement II is true: Statement II is a correct explanation for statement I.
B. (b)Statement I is true, Statement II is true, Statement II is NOT a correct explanation for Statement I.
C. (c)Statement I is true, Statement II is false
D. (d)Statement I is false: Statement II is true

Explanation

To solve the question, we need to analyze both statements provided:

**Statement I:** If two people talk simultaneously and each creates an intensity of 60 dB at a point P, then the total intensity level at point P is 120 dB.

**Statement II:** Sound level is defined on a non-linear scale.

### Step-by-Step Solution:

1. **Understanding Decibels (dB):**
- The decibel scale is a logarithmic scale used to measure sound intensity. The formula to convert intensity (I) to sound level (L) in decibels is:
\[ L = 10 \log_{10} \left( \frac{I}{I_0} \right) \]
where \(I_0\) is the reference intensity, typically \(10^{-12} \text{ W/m}^2\).

2. **Analyzing Statement I:**
- If each person creates an intensity level of 60 dB, we can find the corresponding intensity using the formula:
\[ 60 = 10 \log_{10} \left( \frac{I}{I_0} \right) \]
Rearranging gives:
\[ \frac{I}{I_0} = 10^{6} \implies I = 10^{6} \times I_0 \]
- The intensity corresponding to 60 dB is the same for both people, so if both are talking simultaneously, the total intensity \(I_{total}\) at point P is:
\[ I_{total} = I_1 + I_2 = 10^{6} I_0 + 10^{6} I_0 = 2 \times 10^{6} I_0 \]
- To find the total sound level \(L_{total}\):
\[ L_{total} = 10 \log_{10} \left( \frac{I_{total}}{I_0} \right) = 10 \log_{10} \left( \frac{2 \times 10^{6} I_0}{I_0} \right) = 10 \log_{10} (2 \times 10^{6}) = 10 \left( \log_{10} 2 + 6 \right) \]
- Since \(\log_{10} 2 \approx 0.301\), we find:
\[ L_{total} \approx 10(0.301 + 6) = 10 \times 6.301 = 63.01 \text{ dB} \]
- Therefore, the total intensity level at point P is approximately 63.01 dB, not 120 dB. Thus, **Statement I is false.**

3. **Analyzing Statement II:**
- The sound level is indeed defined on a non-linear scale because it is based on a logarithmic relationship. This means that equal increases in dB do not correspond to equal increases in intensity. Hence, **Statement II is true.**

### Conclusion:
- **Statement I is false.**
- **Statement II is true.**

Therefore, the correct answer is that Statement I is incorrect and Statement II is correct.

### Final Answer:
- Statement I: False
- Statement II: True