Heat and temperature
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13. Heat transfer. Thermal radiation

Figure 7.18
A) Thermal energy radiates from the sun and transfers heat to the earth. B) Thermal energy radiates from a fire and warms a persons hands. ~
This is also how the sun’s energy reaches Earth and heats its surface.

Without the energy radiated from the sun, Earth would be too cold to support life as we know it.

Everything radiates thermal energy, not just really hot things such as the sun or a fire.

For example, when it’s cold outside, a heated home radiates some of its thermal energy into the outdoor environment.

Even people radiate thermal energy. In fact, when a room is full of people, it may feel noticeably warmer because of all the thermal energy the people radiate!

Do you know about thermal cameras, or infrared cameras?

All objects emit thermal energy, or infrared heat waves,known as a heat signature.
An infrared camera (also known as a thermal imager) detects and measures the infrared energy of objects.

Infrared cameras work by capturing heat energy invisible to the naked eye to form an image.

You can check out more about infrared images clicking on the image on the right

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