Current electricity practice · Medium

Number of electrons flowing per second is a conductor carrying a current of $9 {~A}$ is_____

In which one of the following substances the resistance decreases with increase of temperature?

Statement-I: Net power supplied by a non-ideal battery is $\mathrm{Ei}-\mathrm{i}^2 \mathrm{r}$
Statement-II: Power consumed by internal resistance of a battery is $\mathrm{i}^2 \mathrm{r}$.

Which of the following material is the best conductor of electricity?

When two resistances ${R_1}\,\,\mathrm{and}\,\,{R_2}$ are connected in series, they consume $\mathrm{12}\,\,\mathrm{W}$ powers. When they are connected in parallel, they consume $\mathrm{50}\,\,\mathrm{W}$ powers. What the ratio of the powers of ${R_1}\,\,\mathrm{and}\,\,{R_2}$ ?

Two identical heater filaments are connected first in parallel and then in series. At the same applied voltage, the ratio of heat produced in same time for parallel to series will be:

As the temperature increases, the electrical resistance:

In a potentiometer experiment, the balancing length with a cell is $560\,cm$. When an external resistance of $10\,\Omega$ is connected in parallel to the cell the balancing length changes by $60\,cm$. The internal resistance of the cell in ohm is

In an experiment to measure the internal resistance of a cell by potentiometer, it is found that the balance point is at a length of $2\,\,m$ when the cell is shunted by a $5\,\,\mathrm{\Omega }$ resistance; and is at a length of $3\,\,m$ when the cell is shunted by a $10\,\,\mathrm{\Omega }$ resistance. The internal resistance of the cell is, then

Assertion (A)In a meter bridge experiment, null point for an unknown resistance is put inside an enclosure maintained at a higher temperature. The null point can be obtained at the same ${p}$ as before by decreasing the value of the standard resistance.

Reason (R) Resistance of metal increases with increase in temperature.

Two resistances are connected in two gaps of a meter bridge. The balance point is $\mathrm{20}\,\,\mathrm{cm}$ from the zero end. A resistance of $15\,\,\mathrm{\Omega }$ is connected is series with the smaller of the two. The null point shifts to $\mathrm{40}\,\,\mathrm{cm}$. The value of the smaller resistance in $\mathrm{ohm}$ is

When two resistances ${R_1}$ and ${R_2}$ are connected in series and parallel with $120\,\,V$ line power consumed will be $25\,\,W$ and $100\,\,W$ respectively. Then the ratio of power consumed by ${R_1}$ to that consumed by ${R_2}$ will be

Which of the following relation is wrong?

Lengths of two wires are $50 {~cm}, 100 {~cm}$ respectively and their diameters are $1 {~mm}, 2$ ${mm}$ then ratio between their specific resistances is

In a potentiometer experiment the balancing length, with a cell is $560\,cm$. When an external resistance of $10\,\Omega$ is connected in parallel to the cell, the balancing length changes by $60\,cm$. Find the internal resistance of the cell.

A potential difference is applied across the ends of a metallic wire. If the potential difference is doubled, the drift velocity will

Two resistance ${R_1}$ and ${R_2}$are made of different materials. The temperature coefficient of the material of ${R_1}$ is α and of the material of ${R_2}$ is $- \beta$. The resistance of the series combination of ${R_1}$ and ${R_2}$ will not change with temperature, if ${R_1}/{R_2}$ equals

A cylindrical wire is stretched to increase its length by $10 \%$. Calculate the percentage increase in resistance.

The electrolyte used in Lechlanche cell is

The amount of heat produced in a resistor when a current is passed through it can be found using

For a battery the electromotive force is $1.5 \mathrm{~V}$. Terminal velocity is $1.25 \mathrm{~V}$. power supplied to external resistance is $2.5 \mathrm{~W}$. Find the internal resistance of the battery

Identify the correct variation of drift velocity $\left({v}_{{d}}\right)$ with electric field strength $({E})$:

A copper and a chromium voltmeter are connected in series with a battery. It found that in half an hour $0.475\,\,g$ of copper and $0.130\,\,g$ of chromium have been deposited. The ECE ratio of copper and chromium is

If $400\,\,\mathrm{\Omega }$ of resistance is made by adding four $100\,\,\mathrm{\Omega }$ resistance of tolerance $\mathrm{5}\,\,\mathrm{\% }$, then the tolerance of the combination is

An electric lamp is marked $\mathrm{60}\,\,\mathrm{W}$, $\mathrm{230}\,\,\mathrm{V}$. The cost of kilowatt hour of power is $\mathrm{Rs }\,\mathrm{1}\mathrm{.25}$. The cost of using this lamp $\mathrm{8}\,\,\mathrm{h}$ a day for $\mathrm{30 }\,\mathrm{days}$ is

The rate of increase of thermo $e.\mathrm{m}\mathrm{.f}\mathrm{.}$ with temperature at the neutral temperature of a thermocouple

In a potentiometer circuit a cell of EMF 1.5 V gives balance point at 36 cm length of wire. If another cell of EMF 2.5 V replaces the first cell, then at what length of the wire, the balance point occurs?

Kirchhoff’s second law is based on the law of conservation of

A resistor of $6 {k} \Omega$ with tolerance $10 \%$ and another resistance of $4 {k} \Omega$ with tolerance $10 \%$ are connected in series. The tolerance of the combination is about

Two bulbs, one of $50\,\,watt$ and another of $25\,\,watt$ are connected in series to the mains. The ratio of the currents through them is