Stephen A. Lawrence <[email protected]> wrote: Now, most of the energy of the bulb gets lost via convection to the air, > just as most of the energy of the hose gets lost that way. For simplicity, > let's assume the hose and the bulb both lose *all* their energy that way. >
That's fine for this estimate, but in real life a 3 m hose with hot water or steam flowing through it does not lose all of the energy that way. As you see in the video it was still plenty hot at the end. > That's about 40 degrees C, or about 104 degrees F. Even if I'm off by a > factor of 1.5 in one of the assumptions it's still not going to be > especially uncomfortable to touch a rubber hose which is that hot. > My seat-of-the-pants estimate is that it would not be sensibly hotter than the surroundings, or barely sensible. That is because a hose is reasonably good insulation and water heated at one end will be nearly as hot at the other end, at these flow rates. - Jed
