A student has two wires of iron and copper of equal length and diameter. He first joins two wires in series and passes an electric current through the combination which increases gradually. After that he joins two wires in parallel and repeats the process of passing current. Which wire will glow first in each case?

A boy has two wires of iron and copper of equal length and diameter. He first joins the two wires in series and passes electric current through this combination which increases gradually with tiem. After that he joins them in parallel and repeat the process of passing the current in this arrangement also. Which wire will glow first in each case and why ?

Two conducting wires of the same material and of equal length and equal diameters are first connected in series and then in parallel in an electric circuit. The ratio of the heat produced in series and parallel combinations would be :

Two conducting wires of the same material and of equal length and equal diameters are first connected in series and then in parallel in an electric circuit. The ratio of the heat produced in series and parallel combinations would be :

Two heater wires of equal length are first connected in series and then in parallel. The ratio of heat produced in the two cases is

Two heater wires of equal length are first connected in series and then in parallel. The ratio of heat produced in two cases is

Two heater wires of equal length are first connected in series and then in parallel. The ratio of heat produced in the first and second cases is :