What can the Sun Melt? An Experiment in Concentrating the Sun's Energy

Somewhere my children learned you could set fire to things using a magnifying glass and the sun's energy, and they immediately wanted to try out this new found knowledge. To prevent fire damage, I suggested trying to melt things instead

Supplies Needed to Test the Sun's Strength

• Plates (any will work; we used plastic, so they wouldn't break)
• Various sweets that have different consistencies
• Magnifying Glass
• A Sunny Day 

How We Discovered What the Sun Would Melt

We started simple, I gave each of the girls a plate with a large marshmallow, a small 3 Musketeers candy bar, and a section of a Hershey's milk chocolate bar. We left these in the sun for about 30 minutes without much change. 

I was willing to leave them longer, but the girls were eager to get on with the experiment. So out came the magnifying glasses. 

To really get a magnifying glass to heat something up you have to use it to concentrate all the sun's rays into one small area. 

Finding the correct angle was the most time consuming part!  

Once they did they impatiently held the magnifying glass there for a couple minutes.

Literally a couple minutes.

Maybe we would have seen more results if the kids were a bit more patient, but we did see results!

How Strong are the Sun's Rays

First up the marshmallow. The girls thought it would grow like it does in the microwave, but after a couple minutes with the magnifying glass it remained. Slightly warmer, but still marshmallow shaped.

Next, the 3 Musketeers, this they thought would melt because it is chocolate wrapped in chocolate after all. After a couple minutes it was slightly softer to the touch, but it held it's shape.

Lastly, the milk chocolate. Like the previous chocolate, they figured this one would melt, and this time they were right. After just a couple minutes the milk chocolate was showing definite signs of melting. 

It was even more obvious when they stuck their fingers in it, and their fingers ended up covered in chocolate! Not that they minded licking them in the least!

The secret to making this work, just like the secret to lighting things on fire, is to hold the magnifying glass at an angle to the sun. 

When you have the right angle, a small bright dot will appear on whatever you are trying to heat up; the sun's energy is all concentrated on that dot. 

The smaller the dot, the stronger the energy! Now that you know, what will you melt?

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