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Which surface will have the least emissivity?

Which surface will have the least emissivity? Correct Answer Aluminium foil

The emissivity of the surface of a material is its effectiveness in emitting energy as thermal radiation.

Materials surface

Thermal emissivity

Silver, polished

0.02

Aluminum foil

0.03

Marble, smooth

0.56

Paper, roofing or white

0.88 to 0.86

Asphalt

0.88

Plaster, rough

0.89

Brick

0.90

Marble, polished or white

0.89 to 0.92

Concrete, rough

0.91

Glass, smooth (uncoated)

0.91

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