Current electricity practice · Mixed difficulty

The Kirchhoff's second law $(\Sigma i R=\Sigma E),$ where the symbols have their usual meanings, is based on

In a conductor if $\mathrm{3000}\,\,\mathrm{coulomb}$ of charge enters and $\mathrm{3000}\,\,\mathrm{coulomb}$ of charge exits in time $\mathrm{10}\,\,\mathrm{minutes}$, then the current is

$40 \,{~W}, 220 \,{~V}$ and $110 \,{~W}, 220\, {~V}$ bulbs are connected in series with $440\, volt$ supply, then

Statement-1: Potential difference across the terminals of a battery can be greater than its emf.
Statement-2: When current is taken from battery, $V={\varepsilon}- Ir$ (Symbols have their usual meaning).

One $kilowatt$ hour is equal to

Forty electric bulbs are connected in series across a $220\,\,V$ supply. After one bulb is fused, the remaining $\mathrm{39}$ are connected again in series across the same supply. The illumination will be

The colour code of a resistor is brown, black and brown. Then the value of resistance is

A technician has only two resistance coils. By using
them singly in series or in parallel, he is able to obtain
the resistance 1.5, 2, 6 and 8 ohms. The resistance
of two coils are

The material of wire of potentiometer is

If an increase in length of copper wire is $\mathrm{0}\mathrm{.5}\,\,\mathrm{\% }$ due to stretching, the percentage increase in its resistance will be

An electron (charge $= 1.6\,\, \times \,\,{10^{ - 19}}\,\,coulomb$) is moving in a circle of radius $5.1\,\, \times \,\,{10^{ - 11}}\,\,m$ at a frequency of $6.8\,\, \times \,\,{10^{15}}\,\,revolutions/sec$. The equivalent current is approximately

When a current of $\mathrm{1}\,\,\mathrm{ampere}$ is passed through a conductor whose ends are maintained at temperature difference of $1\,{\,^0}\mathrm{C}$, the amount of heat evolved or absorbed is called

Assertion: Electric field outside the conducting wire which carries a constant current is zero.

Reason: Net charge on conducting wire is zero.

In the series combination of $n$ cells each cell having emf $\varepsilon$ and internal resistance $r$. If three cells are wrongly connected, then total emf and internal resistance of this combination will be

Two bulbs $\mathrm{40}\,\,\mathrm{W}$ and $\mathrm{60}\,\,\mathrm{W}$ and rated voltage $\begin{array}{llllllllllllllllllll} {\mathrm{240}\,\,\mathrm{V}} \end{array}$ are connected in series across a potential difference of $\begin{array}{llllllllllllllllllll} {\mathrm{420}\,\,\mathrm{V}} \end{array}$. Which bulb will work at above its rated voltages?

Statement-1: Two unequal resistances are connected in parallel across a cell, then current through the smaller resistor is more.
Statement-2: More current will flow through a larger resistor.

A block of metal is heated directly by dissipating power in the internal resistance of block. Because of temperature rise, the resistance increases exponentially with time and is given by $\mathrm{R}(\mathrm{t})=0.5 \, \mathrm{e}^{2 \mathrm{t}}$, where $\mathrm{t}$ is in second. The block is connected across a $110 \mathrm{~V}$ source and dissipates $7644 \mathrm{~J}$ heat energy over a certain period of time. This period of time is ______ $\times 10^{-1}$ sec.

The Petlier coefficient of a thermo-couple of metls $A$ and $B$ at junction temperature $T$ is given by

Two heaters $A$ and $B$ have power rating of $1 \mathrm{~kW}$ and $2 \mathrm{~kW},$ respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is:

If negligibly small current is passed though a wire of length $15 \mathrm{~m}$ and resistance of $5 \Omega$, having uniform cross section of $6 \times 10^{-7} \mathrm{~m}^2$, then coefficient of resistivity of material is

Some electric bulbs are connected in series across a $\mathrm{220}\,\,\mathrm{V}$ supply in a room. If one bulb is fused, then remaining bulbs are connected again in series across the same supply. The illumination in the room will be

The current inside a copper voltameter

The speed at which the current travels, in a conductor, is nearly

The internal resistance of a cell is the resistance of :

The conductivity of a superconductor is

If an ammeter is connected in parallel to a circuit, it is likely to be damaged due to excess

The net resistance of a voltmeter should be large to ensure that

Which of the following statements is correct

In India electricity is supplied for domestic use at $\mathrm{220}\,\,\mathrm{V}$. It is supplied at $\mathrm{110}\,\,\mathrm{V}$ in USA. If the resistance of a $\mathrm{60}\,\,\mathrm{W}$ bulb for use in India is $R$,the resistance of a $\mathrm{60}\,\,\mathrm{W}$ bulb for use in USA will be

Faraday’s ${\mathrm{2}^{\mathrm{nd}}}$ law states that mass deposited on the electrode is directly proportional to