To test if you can successfully work with energy relate units we ask you to carry out a simple calculation. Scenario: I made it to the office to give my lecture but I forgot my boiling spaghetti on the stove. Do I need to cancel class and rush home to prevent a fire? You can assume: 4 liters of water at boiling point stove setting delivers 250W You are asked to calculate how many minutes it will take for all water to evaporate.