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Upper El (2/8-12): The Speed of Light

This week, our main focus was on finishing our Science Fair reports and boards, which we did! On Thursday, we explored the next lesson on Radiant Energy: the speed of light.

On Thursday, at home, without access to our Science Fair boards, we had an opportunity to return to our current unit on Radiant Energy. We last learned about the entire spectrum, from Radio Waves to Gamma Rays, and this week we explored the one thing they all have in common. They are all "light," and they all travel at the speed of light.

So, how fast is the speed of light? It's so fast that it's hard to comprehend just how fast it is! We started small. How far is it from DGS to Charlotte, and how long does it take us to drive there? Then, how long would it take if we traveled at the speed of light? Any guesses?

The answer: 0.00011 seconds.

Again, that's so fast that it's hard to understand. So, we went further. DGS to Asheville. Charlotte to NYC. Charlotte to LA, to London, to Tokyo! Almost 7,000 miles to get to Tokyo, and still, a beam of light would only take 0.03 seconds.

Finally, we had to back down and ask, just how far could we go in one second? We could go around the world 7.5 times! Now, students were starting to really grasp just how fast the speed of light is.

That led us to see how big our Solar System is by looking at how long it takes light to get to certain places. 1.28 seconds to the moon. 3.5 minutes to go from Earth to Mars. And the light from the Sun takes over 8 minutes to reach us here.

Sorry for all the math, but I love this stuff! And, thankfully, so did the class : )

To end the lesson, we watched a video:

It's a video of what a beam of light would see as it left the Sun, traveling at the speed of light, of course. It's 45 minutes long, and by that point, we only get to Jupiter! We fast-forwarded a lot, watching as we zipped by each planet, Mr. Derek commentating as we traveled the Solar System.

It was a fun week, and next week, with our Science Fair project finished, we'll get to continue learning all about Radiant Energy.

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