$A$ current of $2 \, A$ flows in an electric circuit as shown in the figure. The potential difference $(V_R - V_S)$, in volts ($V_R$ and $V_S$ are potentials at $R$ and $S$ respectively) is:

When an air bubble of radius $r$ rises from the bottom to the surface of a lake,its radius becomes $\frac{5r}{4}$. If the atmospheric pressure is equal to the pressure exerted by a $10 \ m$ height of water column,and the temperature remains constant while surface tension is neglected,what is the depth of the lake (in $m$)?

Give scientific reasons: Frogs undergo summer sleep and winter sleep (aestivation and hibernation).

If the magnetic dipole moment of an atom of diamagnetic material,paramagnetic material and ferromagnetic material are denoted by $\mu_d$,$\mu_p$ and $\mu_f$ respectively,then

The sum of the solutions of the equation $|\sqrt{x}-2|+\sqrt{x}(\sqrt{x}-4)+2=0$ for $x>0$ is equal to

Phytochrome is involved in: