Question

A wire when heated shows 2% increase in
Length The increase in cross sectional area
would be?​

Answer 1

Answer:

lets assume the radius is 100cm

2% increase in radius means the new radius would be=100+(2/100)×100=102 cm

when radius was 100 cm Area=Pi×(100)^2=31415.92cm^2=32685.13cm^2

change in area=32685.13-31415.92=1269.21 cm^2

percentage increase=1269.21/31415.92×100=4.04

hence,the cross sectional area increase by 4.04 %