Energy Transferred by Heating
Energy and Thermal Physics

A teaching story: sparkler versus hot drink

Teaching Guidance for 11-14 Supporting Physics Teaching

Feeling the effects of temperature and energy

You are watching a bonfire with a hot drink in one hand and a sparkler in the other. Somebody knocks into you. Which will warm your hand more so causing most pain, the spilt drink or the sparks from the sparkler?

The drink would probably be well under one hundred degrees Celsius whilst the sparks from the sparkler, being white hot metal, are several hundred degrees Celsius.

However the relatively small number of particles in the spark means that it has little energy in its thermal store compared to the drink. So, the spark on your hand is hardly felt whilst spilling the drink most definitely is! The drink warms your skin much more (shifting much more energy) and that is what you feel.

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