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Question
A bimetallic strip is made of aluminium and steel (αAl > αsteel) . On heating, the strip will ______.
Options
remain straight.
get twisted.
will bend with aluminium on concave side.
will bend with steel on concave side.
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Solution
A bimetallic strip is made of aluminium and steel (αAl > αsteel) . On heating, the strip will bend with steel on concave side.
Explanation:
As αAl > αsteel, aluminium will expand more. So, it should have a larger radius of curvature. Hence, aluminium will be on the convex side.
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