Melting Metal with the Solar Heat Ray

Augustin-Jean Fresnel was a French engineer and physicist that invented a special lens for lighthouses during the early 1800s. Today, cheap fresnel lenses can be found in older-model projection televisions.

Samsung projection television

Opened, the lens and screen are removed.

The screen and lens are taped together. The screen and lens are separated by cutting tape.

A base is constructed to allow the frame holder the ability to swivel left and right. A frame is constructed for the lens. The frame will have a bolt on each side to permit moving the beam from the lens up and down. The frame holder is connected to the base. The frameholder can move freely to the left and right.

The base, frame holder, and lens frame are put together.

A large magnifying glass is tested. A temperature of 234.3 degrees Fahrenheit (112 degrees Celsius) is recorded.

A small magnifying glass is tested. A temperature of 389.3 degrees Fahrenheit (189 degrees Celsius) is recorded.

The solar heat ray (Fresnel lens) is tested. The infrared thermometer states a maximum range up to 500 degrees Fahrenheit. A temperature of 686.8 degrees Fahrenheit is recorded.

The temperature frequently moves out of range of the thermometer.

A jar of water is heated with the solar heat ray and the water boils.

A penny is caught in the heat ray and melts.

The penny becomes unrecognizable.

Made mostly of zinc, pennies melt at a temperature of 787 degrees Fahrenheit (419.4 degrees Celsius).

Temperatures exceeding 787 degrees Fahrenheit (419.4 degrees Celsius) are recorded with the Fresnel lens in the sun. The experiment can give you an idea of how inhospitable the planet Venus is. Though it is the closest planet to Earth, Venus maintains an average temperature of 864 F (462 C).

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