$30 QUESTION -- Category: Energetic Terms

What's "U-value?"

  1. A measure of the sea-worthiness of a submarine. The higher the "underwater" rating, the better the boat.

  2. A way to measure the price of your underwear. A high rating means it costs more.

  3. A measure of heat flow through a window, indicating its insulating ability. The smaller the U-value, the better insulating the window.


 Click on the answer you think is correct!