AP and TS EAMCET Medical Model Paper 4

Two rods, one of aluminium and the other made of steel, having initial length l1 and l2 are connected together to form a single rod of length l1 +l2 . The coefficients of linear expansion for aluminium and steel are αa and αs respectively. If the length of each rod increases by the same amount when their l 1 temperatures are raised by t°C, then find the ratio

l1

l1+l2