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Manipal MET2012PhysicsWaves and Sound

A sound has an intensity of 2 10⁻⁸ ~W / m ^2 . Its intensity level in decibels is ( ₁₀ 2=0.3 )

Options

  1. A23
  2. B3
  3. C43
  4. D4.3

Correct answer

C. 43

Step-by-step solution

aligned L & =10 ₁₀ ( I I₀ ) L & =10 ₁₀ ( 2 10⁻⁸ 10⁻² ) & ( I₀=10⁻¹² ~W / m ^2 ) L & =10 ₁₀ (2 10^4 ) L & =10 [ ₁₀ 2+ ₁₀(10)^4 ] L & =10(4.3) L & =43 decibel aligned

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