Question

Energy from the Sun arrives at the top of the Earth's atmosphere with an intensity of 1.30 kW/m². How long does it take for 1.8×10⁹ J to arrive on an area of 1.00 m²?

Answer 1

P(power) = 1.30 kW/m^2 / sec = 1.30E3 J/m^2 / sec

Since 1 W = 1 J/sec

E = P t

t = 1.8E9 J / 1.3E3 J/sec= 1.4E6 sec

t = 1,400,000 sec