Question

The average sound intensity inside a busy restaurant is 3.10 10-5 W/m2. How much energy goes into each ear (area = 2.1 10-3 m2) during a 1 hour meal?

Answer 1

Explanation:

Below is an attachment containing the solution.

Answer 2

Answer:

2.344×10⁻⁴ J

Explanation:

Energy: This can be defined as the ability or the capacity to do wok.

The S.I unit of energy is Joule(J).

From the question,

E = P×t.............. Equation 1

Where E = amount of energy that goes into the ear, P = power, t = time.

But,

P = I×A.............. Equation 2

Where I = sound intensity, A = cross sectional area.

Substitute equation 2 into equation 1

E = I×A×t................ Equation 3

Given: 3.1×10⁻⁵ W/m², A = 2.1×10⁻³ m², t = 1 hour = 1×60×60 =  3600 s

Substitute into equation 3

E = 3.1×10⁻⁵× 2.1×10⁻³× 3600

E = 2.344×10⁻⁴ J.