A sound wave with a power of 8 point 8 times 10 to the negative 4 power cap w leaves a speaker and passes through section A, which has an area of 5 point 0 m squared What is the intensity of sound in this area? open paren Intensity is equal to cap i is equal to the fraction with numerator cap p o w e r and denominator mathrm cap A r e A close paren
Answer
A
1 point 8 times 10 to the negative 6 power the fraction with numerator cap w and denominator m squared
B
1 point 8 times 10 to the negative 4 power the fraction with numerator cap w and denominator m squared
C
1 point 6 times 10 to the negative 6 power the fraction with numerator cap w and denominator m squared
D
1 point 6 times 10 to the negative 4 power the fraction with numerator cap w and denominator m squared
Explanation
Sound intensity is power divided by area: I = P/A. Substituting the given values gives I = (8.8 × 10⁻⁴ W)/(5.0 m²) = 1.76 × 10⁻⁴ W/m², which rounds to 1.8 × 10⁻⁴ W/m². Therefore, the correct choice is 1.8 × 10⁻⁴ W/m².
AI-written and checked against the verified answer.