The intensity of radiation reaching the Earth from the Sun is 1350 W/m². The Earth's radius is 6.4 × 106 m. How big a force does this radiation exert on the Earth? (Assume it is all absorbed.)

Question

Quizplus · Accepted Answer

The force exerted by radiation is given by the equation F = P/c, where P is the power of the radiation and c is the speed of light. In this case, the power of the radiation is 1350 W/m2 and the radius of the Earth is 6.4 × 106 m. So, the force exerted by the radiation is:F = P/c = (1350 W/m2) * (6.4 × 106 m) / (3 × 108 m/s) = 5.8 × 108 N

The Intensity of Radiation Reaching the Earth from the Sun