Final answer:
Water entering hot rocks in Earth leads to a conversion of thermal energy to mechanical and then electrical energy via geothermal power generation, involving calculations of heat transfer and the duration of energy conversion based on the power output rate.
Step-by-step explanation:
When water enters hot rocks in Earth, there is a conversion of thermal energy to mechanical energy, specifically in the context of generating electricity using geothermal energy. The heat transfer from the hot rocks to the water heats the water and may cause it to turn into steam. This steam can then be used to drive turbines, which convert the thermal energy into electrical energy. The amount of heat that can be extracted by cooling a volume of rock, and the time it would take for this energy to transfer at a given rate, are important considerations in geothermal power generation and can be calculated using principles of thermodynamics. For example, to calculate the energy extracted by cooling 1.00 km³ of granite by 100°C, one must know the specific heat of granite, the mass of the granite, and the temperature change. The calculation for how long it takes for the heat transfer would then take into account the power output and the total amount of energy to be transferred.