V-i graphs for two wires a and b are shown in the figure. if we connect both the wiresone by one to the same battery which of the two will produce more heat per unit time? justify your answerв(2)

Greater than slope of V-I graph, greater will be the resistance of given metallic wire. In the given graph, wire A has greater slope then B. Hence, wire A has greater resistance.
For the wires of same length and same thickness, resistance depends on the nature of material of the wire

a subpoena, i think. hope this helps!! :)