$Assertion :$ A hollow metallic closed container maintained at a uniform temperature can act as a source of black body radiation.
$Reason :$ All metals act as black bodies.
$Reason :$ All metals act as black bodies.
AIIMS 2007, Easy
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A perfect black body is one which absorbs all heat radiations (whatever be the
wavelength) incident on it. No natural object is a perfect black body. Best approximations are lamp black and platinum black. Fery's black body is a double walled metallic sphere coated with lamp black on the inside and nickel on outside. It has a narrow opening opposite a conical projection inside.
wavelength) incident on it. No natural object is a perfect black body. Best approximations are lamp black and platinum black. Fery's black body is a double walled metallic sphere coated with lamp black on the inside and nickel on outside. It has a narrow opening opposite a conical projection inside.
$\therefore $ Both Assertion and Reason are incorrect
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