JEE Main - 31 August 2021 Shift 1

If the potential difference between $B$ and $D$ is zero, the value of $x$ is $\frac{1}{n} \mathrm{\Omega }$. The value of $n$ is ______.

Two identical cells, when connected either in parallel or in series gives same current in an external resistance $5 \mathrm{\Omega }$. The internal resistance of each cell will be ______ $\mathrm{\Omega }$.

The $H$ amount of thermal energy is developed by a resistor in $10 \mathrm{s}$ when a current of $4 \mathrm{A}$ is passed through it. If the current is increased to $16 \mathrm{A}$, the thermal energy developed by the resistor in $10 \mathrm{s}$ will be

The equivalent resistance between $A and B$ of the network shown in figure:

In an experiment to find emf of a cell using potentiometer, the length of null point for a cell of emf $1.5 \mathrm{V}$ is found to be $60 \mathrm{cm}$. If this cell is replaced by another cell of emf $E$. the length-of null point increases by $40 \mathrm{cm}$. The value of $E$ is $\frac{x}{10} \mathrm{V}$. The value of $x$ is ______.

Equivalent resistance between the adjacent corners of a regular $n$-sided polygon of uniform wire of resistance $R$ would be :

A water heater of power $2000 \mathrm{W}$ is used to heat water. The specific heat capacity of water is $4200 \mathrm{J} {\mathrm{kg}}^{-1} {\mathrm{K}}^{-1}$. The efficiency of heater is $70\%$. Time required to heat $2 \mathrm{kg}$ of water from $10°\mathrm{C}$ to $60°\mathrm{C}$ is _____ $\mathrm{s}$.

(Assume that the specific heat capacity of water remains constant over the temperature range of the water).

In the given circuit the value of $\left|\frac{I_1+I_3}{I_2}\right|$ is: