An electric heater rated $600 \ W$ operates $6$ hours per day. Find the cost to operate it for $30$ days at ₹ $3.00$ per unit.

Of the two bulbs in a house, one glows brighter than the other. Which of the two has a larger resistance?

Define power. State the difference between $1$ watt and $1$ watt hour. Establish the relationship between the commercial unit of electric energy and the $SI$ unit of energy. An electric heater rated $1000 \ W / 220 \ V$ operates for $2$ hours daily. Calculate the cost of energy to operate it for $30$ days at the rate of ₹ $5.00$ per $kWh$.

What is the current flowing through a $60 \ W$ bulb when it is connected to a $240 \ V$ line?

An electric bulb is rated at $200 \ V - 100 \ W$. What is its resistance? If five such bulbs burn for $4 \ hours$, what is the total electrical energy consumed? Calculate the cost, if the rate is $50$ paise per unit.

An electric heater of resistance $8 \, \Omega$ draws $15 \, A$ from the service mains for $2$ hours. Calculate the rate at which heat is developed in the heater (in $W$).