Current Electricity Questions

A material $B$ has twice the specific resistance (resistivity) of $A$. A circular wire made of $B$ has twice the diameter of a wire made of $A$. For the two wires to have the same resistance, the ratio $L_A/L_B$ of their respective lengths must be:

Kirchhoff’s first law ($\sum i=0$) and second law ($\sum iR=\sum E$) are respectively based on the conservation of:

In a Wheatstone’s bridge, three resistances $P,Q$ and $R$ are connected in three arms and the fourth arm is formed by two resistances $S_1$ and $S_2$ connected in parallel. The condition for the bridge to be balanced is:

The current $I$ drawn from the $5\text{V}$ source in the following circuit is:

The resistance of a bulb filament is $100\Omega$ at a temperature of $100^{\circ }\text{C}$. If its temperature coefficient of resistance be $0.005$ per ${}^{\circ }\text{C}$, its resistance will become $200\Omega$ at a temperature of:

An electric bulb is rated $220\text{V}-100\text{W}$. The power consumed by it when operated on $110\text{V}$ will be:

An inductor ($L=100\text{mH}$), a resistor ($R=100\Omega$) and a battery ($E=100\text{V}$) are connected in series. After a long time, the battery is disconnected after short-circuiting. The current in the circuit $1\text{ms}$ after the short-circuit is: