Egg Shell DurabilityPurpose:
A good test of a model rocket’s ability is to fly a raw hen’s egg in its payload compartment and retrieve it unharmed. It is a scalable feature for people in spacecraft. But just like a space agency will pick and choose its astronauts to minimize the potential of injury or unconsciousness, certain eggs will hold up better than others in a model rocket at seven g’s.
- Store-bought large grade A hen eggs
- Homegrown leghorn (white)
- Homegrown barred rock (brown)
- Homegrown araucana (green)
- Or any other type of chicken egg you have at your disposal
- Modeling clay, sand, or ballast of your choice
- Big bowl
- Triple-beam balance
(a) Place egg under big bowl.
(b) Gently place more ballast into bowl until egg breaks (gently because you don’t want more acceleration than 9.8 m/s2).
(c) Weigh the ballast and the bowl.
(d) Repeat for each type of egg.
(#Test, egg type, mass held when crushed)
- Store-bought egg from Aldi: 2712g = 2.712kg
- Store-bought egg from Aldi: 2296g = 2.296kg
- Brown: 3128g = 3.128kg
- Brown: 3336g = 3.336kg
- White: 3636g = 3.636kg
- White: 4493g = 4.493kg
- Green: 3534g = 3.534kg
- Green: 3169g = 3.169kg
Average force to crush Aldi eggs:
F = (m*g + m*g)/2 = (2.296kg*9.8m/s/s + 2.712kg*9.8m/s/s)/2 = 24.50N
Average force to crush brown eggs:
F = (3.128kg*9.8m/s/s + 3.336kg*9.8m/s/s)/2 = 31.67N
Average force to crush white eggs:
F = (3.636kg*9.8m/s/s + 4.493kg*9.8m/s/s)/2 = 39.83N
Average force to crush green eggs:
F = (3.534kg*9.8m/s/s + 3.169kg*9.8m/s/s)/2 = 32.84N
No space agency would pick an astronaut that blacks out at 4g's. Therefore, it doesn't make sense to choose an egg that will scramble in its payload compartment if a force of just 24.5 Newtons is applied to it.
Therefore, for maximum flight performance, the egg with the best qualifications is laid by the white leghorn. Moreover, a farm-fresh white leghorn egg should be used. The ratio of Newtons held by farm-fresh leghorn and Newtons held by Aldi egg is a staggering 1.63.