Masses of three wires are in the ratio 1:3:5. Their lengths are in the ratio 5:3:1. When connected in series with a battery, the ratio of heat produced in them will be

We know that , H=i2R∴ H=i2(ρl/A)=i2ρl2dmor H∝l2/mor H1:H2:H3=(5)21:(3)23:(1)25or H1:H2:H3=125:15:1Note. when they are connected in parallel, thenH=V2/R  or  H∝m/l2∴ H1:H2:H3=1:15:125