Question

The intensity of electromagnetic waves from the sun is 1.4kW/m2 just above the earth's atmosphere. Eighty percent of this reaches the surface at noon on a clear summer day. Suppose you think of your back as a 30.0 cm × 51.0 cm rectangle. How many joules of solar energy fall on your back as you work on your tan for 1.30 hr ?

Answer 1

Explanation:

Below is an attachment containing the solution.

Answer 2

Answer:

$E=8.02*10^{5}J$

Explanation:

Given data

Electromagnetic waves from the sun is I=1.4kW/m² at 80%

Area a=(0.30×0.51)m²

Time t=1.30 hr

To find

Energy E

Solution

The energy received by your back is calculated as:

$E=Pt=Iat\\E=(0.80)(1400W/m^{2} )(0.30*0.51m^{2} )(1.30*3600s)\\E=8.02*10^{5}J$