A thin copper wire of length $$l$$ metre increases in length by $$2\% $$ when heated through $${10^ \circ }C.$$ What is the percentage increase in area when a square copper sheet of length $$l$$ metre is heated through $${10^ \circ }C$$ ?
A.
$$4\% $$
B.
$$8\% $$
C.
$$16\% $$
D.
None of these
Answer :
$$4\% $$
Solution :
Since percentage increase in length $$ = 2\% $$
Hence, percentage increase in area of square sheet $$ = 2 \times 2\% = 4\% $$
Releted MCQ Question on Basic Physics >> Unit and Measurement
Releted Question 1
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