Estimate the energy stored in a match

AI Thread Summary
The discussion centers on estimating the energy released by burning a match, with an approximate value of 1 BTU (over 1 kJ) found through research. The participant initially compares the match's power output to that of a 100W lightbulb, estimating the match at 10W and calculating a total energy of 100J, which is significantly lower than the researched value. They acknowledge that their intuition may have underestimated the match's power output. Suggestions for a more accurate approach include considering different wattage or burn times. Overall, the participant concludes that being within an order of magnitude of the correct answer is a reasonable outcome.
paco_uk
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Homework Statement



This is for a class to learn about making order of magnitude estimates. I want to estimate the amount of energy released by burning a match. Googling gives an answer of about 1BTU (just over 1kJ) but I can't think how to estimate it from general knowledge.

Homework Equations


The Attempt at a Solution



I considered trying to compare the power output of a match to that of a lightbulb. I guessed that a match would be at least a factor of 10 less bright than a 100W lightbulb.

This would give a match a power of 10W so assuming it burns for 10 seconds that would make 100J - a lot less than the correct answer.

I guess my error comes from underestimating the power output of a match but since my intuition was so wildly out, does anyone have an alternative approach that might get closer?

(It would be interesting to try and measure this value by using a lit match to heat some water and measuring the change in temperature but the spirit of this exercise is back of the envelope calculations without experiment)
 
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You have the right idea, and you are within an order of magnitude of the given answer, so IMO that's not a bad result.

Basically, you have both the wattage or the burn time that could be different than what you said they were.
 
Thanks, I guess given the original estimates a factor of 10 isn't that bad after all.
 
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