Two electric bulbs of $40 \text{ W}$ each are connected in series. The power consumed by the combination will be . . . . . . . (in $\text{ W}$)

$A$ uniform heating wire of resistance $36 \, \Omega$ is connected across a potential difference of $240 \, V$. The wire is then cut into half and a potential difference of $240 \, V$ is applied across each half separately. The ratio of power dissipation in the first case to the total power dissipation in the second case would be $1:x$,where $x$ is........... .

Assertion: Long distance power transmission is done at high voltage.
Reason: At high voltage supply,power losses are less.

Two conductors made of the same material are connected across a common potential difference. Conductor $A$ has twice the diameter and twice the length of conductor $B$. The power delivered to the two conductors $P_A$ and $P_B$ respectively is such that $P_A/P_B$ equals to

If a $2\, kW$ boiler is used everyday for $1$ hour, then the electrical energy consumed by the boiler in thirty days is .......... $units$.

The resistance of a bulb filament changes with temperature. If a bulb rated at $220 \ V$ and $100 \ W$ is connected to a supply of $(220 \times 0.8) \ V$,the actual power consumed will be: