Q1. 550J of heat energy is transferred to the system that does 400J of work done. By how much does the energy of system's thermal modify?
Q2. The light energy which falls on a square meter of ground over the course of a usual sunny day is around 20 MJ. Average rate of the electric energy consumption in one house is just about 1.0 kW.
a) On an average, how much energy does one house employ throughout each 24 hour day?
b) If light energy to electric energy conversion by using solar cells is 5% efficient, how many square miles of land should be covered with the solar cells to supply electrical energy for 250,000 houses? Suppose there is no cloud cover.