If the current $I$ through a resistor is increased by $100\%$ (assume that temperature remains unchanged), the increase in power dissipated will be ........ $\%$

State whether the following statement is true or false:
Black surfaces are poor absorbers of heat.

In an electrical circuit,three incandescent bulbs $A, B$ and $C$ of rating $40 \, W, 60 \, W$ and $100 \, W$ respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness?

Two conducting wires of the same material,equal length,and equal diameter are connected in series. How does the heat produced by the combination of resistance change?

An electric iron has a rating of $750\, W; 200\, V$. Calculate:
$(i)$ The current required.
$(ii)$ The resistance of its heating element.
$(iii)$ Energy consumed by the iron in $2$ hours.

An electric kettle of $2 kW$ works for $2 h$ daily. Calculate the $(a)$ energy consumed in $SI$ and commercial units, and $(b)$ cost of running it in the month of June at the rate of ₹ $3.00$ per unit.