Question

The rate of energy flow per unit area of electromagnetic wave has an average value of 0.695 W/m2. The wave is incident at right angles upon a rectangular area measuring 1.5 m by 2.0 m. How much total energy falls upon this rectangle each minute? (\small \epsilon0=8.85 x 10-12 C2/Nxm2, u0=4\small \prodx10-7 Txm/A, c=?3.0 x 108 m/s)

Answer 1

125.1 Joules

Step-by-step explanation:

P = Power

t = Time

A = Area

Intensity is given by

`I=(P)/(A)`

Energy is given by

`E=Pt\\\Rightarrow P=(E)/(t)`

For one second

`(E)/(t)=IA\\\Rightarrow E=IAt\\\Rightarrow E=0.695* 1.5* 2* 1\\\Rightarrow E=2.085\ J`

The energy falling on the rectangle is 2.085 Joules every second

In one minute

`2.085* 60=125.1\ J`

In one minute the energy falling on the rectangle is 125.1 Joules