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A piece of iron is heated in a flame. It...

A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using.

A

Stephen's law

B

Wien's displacement law

C

Kirchoff's law

D

Newton's law of cooling

Text Solution

Verified by Experts

The correct Answer is:
B
Wein's displacement law, `lambda_(m)T =` constant
`rArr lambda_(m) prop 1/T`
so as temperature increases `lambda` decreases.
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Knowledge Check

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