If $10$ bulbs of $100 \ W$ each are kept on for $1 \ \text{hour}$, how much electrical energy is consumed?

Define electric power. Give its $SI$ units and write its mathematical equation.

Two lamps,one rated $100 \, W$ at $220 \, V$ and the other $60 \, W$ at $220 \, V$,are connected in parallel to a $220 \, V$ supply. Find the current drawn from the supply line.

What is meant by "electrical resistance" of a conductor? State how the resistance of a conductor is affected when $(i)$ a low current passes through it for a short duration; $(ii)$ a heavy current passes through it for about $30$ seconds.

An electric refrigerator rated $400 \ W$ operates $8 \ h$ per day. What is the cost of the energy to operate it for $30$ days at ₹ $3.00$ per $kWh$?

The unit $Joule/second$ $(J/s)$ is the unit of which of the following?