Fry an egg on the pavement
This eggsellent experiment brings a whole new meaning to the phrase ‘sunny side up’.
Around the world, some people are so fascinated by the idea of cooking an egg on the pavement, they hold annual contests. In the city of Oatman, Arizona, a Solar Egg Frying Contest occurs every 4 July, with a prize for the resident who can create the most edible-looking fare. Despite the popularity of the phrase, though, very few people have successfully cooked an egg on a pavement without a significant amount of extra help.
Nevertheless, the next time a heat wave hits your area, get outside with your child, grab an egg, and get cracking as a team. There’s nothing like testing out an idea firsthand, and the experience will teach them a great deal about heat conduction and the variables that can affect it.
- If the temperature is warmer than 35º C, put on some sunscreen with your child and head to the brightest, sunniest outdoor spot you can find.
- Together, crack the egg and pour it onto the hot pavement or driveway, making sure that the surface is level and flat.
- Allow the sun to work its magic. Wait a few minutes, checking progress regularly. Eventually, your egg should start to cook.
- If the temperature is less than 35º C, you will need to intensify the heat in order to cook the egg. This can be done by laying a sheet of tinfoil – shiny side up – onto your pavement or driveway (remember: this surface should still be flat and level, and it should still attract direct sunlight).
- Curl up the edges of the tinfoil. Crack your egg, and pour the contents onto the tinfoil. Does this help speed up the process? If so, why does your child think this might be?* If not, what could you do differently?**
- If and when you do manage to cook the egg, do not eat it! Explain why – warning your child about the perils of pesky pavement parasites. Although it’s wonderful for them to experiment in the name of science, they should save the eating for eggs cooked in the kitchen.
* Although pavements do get pretty hot during a heat wave – burning our feet and making our pets miserable – they very rarely get above 60° C, which is the optimum temperature at which to cook an egg. They also conduct heat poorly – meaning that they soak up the heat well, but don’t distribute that heat efficiently to other things, including eggs!
** Top tip: If you’re not having much luck, you may be better off frying the egg on the roof of your car. This is because metal is a greater conductor of heat. You and your child could also use a few extra tools such as a magnifying glass or mirror. Both will magnify the sun’s rays and help speed up the process.