Why is it that when you run your finger through candle flame, you rarely feel the heat, but just a second of flame from petroleum gas can burn you good?

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Why is it that when you run your finger through candle flame, you rarely feel the heat, but just a second of flame from petroleum gas can burn you good?

In: 8

Candles burn at a much lower temperature than natural gas because the flames have different fuels (wax for the candle and natural gas for the gas burner). A bigger temperature difference allows a faster transfer of energy, allowing a burn to develop from the gas burner before the candle.

Simply put, exposure. A petroleum gas flame burns at a higher temperature. Getting burns isn’t about temperature, it’s about transfer. It’s the reason why you can reach into your oven after heating it up to 100 degrees Celsius without suffering a burn, but touching any of the metal inside will burn you even though the temperature is lower than that of the air. The metal transfers the heat faster than the air can. Same with a petroleum flame vs a candle flame, except the petroleum burns hotter, so there’s more heat to transfer from the get go.

You know when you have steam in the bathroom after a shower? And then when making pasta there is steam coming out of the pot? While both of these look the same, one is actually much hotter than the other and could burn you. You can feel the heat from both situations but one is much much hotter.

This is similar to the fire. Even though they’re both hot and fires, due to the different sources they’re actually different temperatures and one is much much hotter.

NOTES: I know bath room “steam” and steam from a boiling pot are different, but they look the same. When you’re 5 you don’t know the difference, so it makes a good analogy.
Also it’s hard to explain fuel source combustion temperatures to a 5 year old since they shouldn’t have much experience with burning different things.

Along with the temperature difference: your finger will rarely spend a whole second in the flame when moving through a candle flame. (Unless it’s a very big donkey candle)

So you’re comparing apples and oranges a bit.