Electric power of a circuit is the rate at which work is done in maintaining the electric current in the circuit.

Which of the following is true for a parallel combination of two resistors?

What is meant by equivalent resistance?

$(a)$ State the commercial unit of electric energy and find its relation with its $SI$ unit.
$(b)$ The current through a resistor is made three times its initial value. Calculate how it will affect the heat produced in the resistor.
$(c)$ Find the increase in the amount of heat generated in a conductor if another conductor of double resistance is connected in the circuit,keeping all other factors unchanged.

Three resistors of $5 \, \Omega$,$10 \, \Omega$,and $15 \, \Omega$ are connected in series,and the combination is connected to a battery of $30 \, V$. An ammeter and a voltmeter are connected in the circuit. Draw a circuit diagram to connect all the devices in the correct order. What is the current flowing through the circuit and the potential difference across the $10 \, \Omega$ resistor?

An electric heater consumes $1.1 \,kW$ power when $220 \,V$ voltage is applied to it. How much current will be flowing through it (in $,A$)?