While browsing the web for kid friendly science activities for my daughters I came across an activity page from a reputable company featuring the egg balancing activity. As I previously mentioned in my Balancing an Egg Myth blog entry, the alignment of the Sun and Earth has nothing to do with balancing an egg. Balancing an egg is all about center of mass. Give it enough time and you will balance an egg. It doesn't matter what time of day, day of the year, or location on Earth. So imagine my surprise when I encountered this "reputable" website feature the egg balancing experiment with the following introductory words:
"Balance an egg on its
end with some skillful coordination, a little salt—and maybe even a little help
from the sun's gravitational pull!"
This introductory statement doesn't directly state that the Sun's gravitational pull plays a significant role, but it certainly implies it. After reading through the procedure I was shocked to see the following:
"Some people believe that the gravitational pull of the sun
that occurs on the equinoxes can help keep an egg standing on its end. This
idea is unproven, but it's interesting to test it. Another way to stand an egg
up—on any day—is to use salt."
What's wrong with this statement? For starters, saying that "this idea is unproven" is a weak statement. It leads one to conclude that the balanced egg could be a result of the Sun's gravitational pull, but that we haven't tested it enough to verify. But it has been tested and tested by children all over the world. Balance an egg on end any day of the year other than the two equinoxes (first day of spring and first day of fall) and you've proven that the Sun's gravitational pull plays no role.
The other misleading item is this statement is the mentioning of salt. It implies that you can balance an egg on any day of the year as long as you have salt. Sorry, but salt is not needed to balance an egg. I've done this every year with my students for 6 years running and we've never used salt. To top that, we've managed to balance several eggs on the narrow end, with no salt in sight.
This website has a number of what appear to be excellent science activities for kids, but if the others are similar to the egg balancing experiment, they are filled with misleading statements that will only work to teach children incorrect science. Very disappointing.
The moral of this story is to be careful. Even reputable websites can be wrong.
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