Final answer:
The power per square meter reaching Earth from the Sun is approximately 1,360 W/m². Part of this is absorbed and reflected by the atmosphere, allowing a maximum of 1.30 kW/m² to reach the surface. An area of solar collectors is calculated by taking into account the power output of a power plant and the conversion efficiency of the collectors.
Step-by-step explanation:
To calculate the power per square meter reaching Earth's upper atmosphere from the Sun, we use the solar constant which is approximately 1,360 W/m². This value represents the solar radiation that arrives at the top of Earth's atmosphere. The total power output of the Sun (P_out) can be represented by the formula 4πR²σT⁴, but for simplicity, we can use the provided value of 4.00 × 10²⁶ W.
To address part (b) of the question, we use the information that a maximum of 1.30 kW/m² reaches Earth's surface after being absorbed and reflected by the atmosphere, and the solar energy collectors have an average conversion efficiency of 2.00%. To provide the output of a 750 MW power plant, we first convert 750 MW to W (750 × 10¶ W), and then calculate the area of the solar energy collectors required as follows:
Area = Power Plant Output / (Intensity × Conversion Efficiency)
Area = (750 × 10¶ W) / (1.30 × 10³ W/m² × 0.02)
The result will give us the area in m², which can be converted to km² by dividing by 10⁶.