Question 1. The light energy that falls on a square meter of ground over the course of a typical sunny day is about 20 MJ. The average rate of electric energy consumption in one house is 1.0 kW.

[A] On average, how much energy does one house use during each 24hr day?

[B] If light energy to electric energy conversion using solar cells is 5% efficient, how many square miles of l& must be covered with solar cells to supply the electrical energy for 250,000 houses? Suppose there is no cloud cover.

Question 2. 550J of heat energy is transferred to a system that does 400J of work. By how much does the system's thermal energy change?