Estimate the energy stored in a match

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SUMMARY

The discussion focuses on estimating the energy released by burning a match, with a commonly cited value of approximately 1 BTU (just over 1 kJ). The participant initially estimated the power output of a match to be around 10W, leading to a calculated energy release of 100J over 10 seconds, which is significantly lower than the accepted value. Feedback indicates that while the initial estimate was an order of magnitude off, it was not entirely inaccurate, suggesting that the participant's approach was reasonable but required adjustments in power output and burn time assumptions.

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  • Understanding of basic thermodynamics and energy units (e.g., BTU, Joules)
  • Familiarity with power calculations and energy conversion
  • Knowledge of lightbulb wattage and brightness comparison
  • Basic principles of heat transfer (e.g., measuring temperature change in water)
NEXT STEPS
  • Research the energy content of common combustible materials, focusing on matches
  • Learn about calorimetry and methods for measuring energy release in chemical reactions
  • Explore the relationship between power output and burn time in combustion processes
  • Investigate the principles of order of magnitude estimation in scientific calculations
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Students in physics or engineering courses, educators teaching thermodynamics, and anyone interested in practical applications of energy estimation techniques.

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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