What is the power of a bulb rated at $2.5 \, V$ and $500 \, mA$ (in $, W$)?

What do you mean by the heating effect of electric current? Explain the production of heat in a resistor by the flow of electric current through it. Name two devices based on the heating effect of current.

State Joule's law of heating.

Elements of electric toasters and electric irons are made of an alloy rather than a pure metal. Give two reasons to justify the statement.

Three $2 \,\Omega$ resistors,$A, B$ and $C,$ are connected as shown in the figure. Each of them dissipates energy and can withstand a maximum power of $18 \,W$ without melting. Find the maximum current $I$ that can flow through the circuit.

You are given a resistance wire of length $50 \,cm$ and a battery of negligible resistance. In which of the following cases is the largest amount of heat generated?