$A$ cable of resistance $10\,\Omega$ carries electric power from a generator producing $250\,kW$ at $10000\,V$. The power lost in the cable during transmission is ............. $kW$.

Two electric bulbs whose resistances are in the ratio of $1:2$ are connected in series. The powers dissipated in them have the ratio:

Two heaters take $10$ minutes and $20$ minutes respectively to heat the same amount of water. If the heaters are connected in parallel,what would be the time required to heat the same amount of water?

When a current flows through a conductor,its temperature:

Heating coils rated at $220\, V$ are available with resistances of $55\,\Omega$,$110\,\Omega$,$220\,\Omega$,and $440\,\Omega$. Which resistance value will produce the maximum power?

It takes $12$ minutes to boil $1$ litre of water in an electric kettle. Due to some defect, it becomes necessary to remove $20\%$ of the turns of the heating coil of the kettle. After repair, how much time will it take to boil $1$ litre of water?