In the given circuit,if point $C$ is connected to the earth and a potential of $+2000 \, V$ is applied to point $A$,what is the potential of point $B$ in volts?

In an acute angled triangle,$\cot B \cot C + \cot A \cot C + \cot A \cot B$ is equal to

If the distance between the centres of the Earth and the Moon is $D$ and the mass of the Earth is $81$ times the mass of the Moon,then at what distance from the centre of the Earth will the net gravitational field be zero?

In $\triangle ABC$,$\frac{r_1-r}{a}+\frac{r_2-r}{b}+\frac{r_3-r}{c} =$

The electronic configurations of $Eu$ (Atomic No $63$),$Gd$ (Atomic No $64$) and $Tb$ (Atomic No $65$) are

$A$ circular coil of area $200 ~cm^2$ and $50$ turns is rotating about its vertical diameter with an angular speed of $40 ~rad/s$ in a uniform horizontal magnetic field of magnitude $2 \times 10^{-2} ~T$. The maximum emf induced in the coil is (in $~V$)