Intensity Formula

Intensity formula

Intensity is the amount of energy a wave carries per unit time over an area of one unit area, which is equal to the energy density multiplied by the velocity of the wave. Usually measured in watts / square meters. The intensity depends on the intensity and amplitude of the wave. Intensity is represented by I. 

The intensity formula is expressed as: 

I = P/A

Here,

I= intensity

P= power

A= area of cross-section

Solved examples

1. Do you want to calculate the strength of a wave with a power of 25KW and a cross-section of 35x106m²?

P = 25 KW = 25×10³ W, A =35×10⁶m²

Intensity formula

I= P/A

I = 25×10³ /35×10⁶

=7.14×10^-2 W/m²

2. Do you calculate the power of waves with intensity and cross-section of 30 × 10^-5W / m² and 50m² respectively?

Given

I= 30×10^-5 W/m²

A= 50 m²

I = P/A

P = I x A

P = 30×10^-5 x 50

P= 0.015 W