When an electric current is passed through acidulated water,$112 \ mL$ of hydrogen gas at $N.T.P.$ is collected at the cathode in $965 \ seconds$. The current passed,in amperes,is:

In the following arrangement,$y = 1.0 \, mm$,$d = 0.24 \, mm$,and $D = 1.2 \, m$. The work function of the material of the emitter is $2.2 \, eV$. The stopping potential $V$ needed to stop the photocurrent will be....$V$

Two large holes are cut in a metal sheet. If this is heated,distances $AB$ and $BC$ (as shown in the figure) will:

The length of the common chord of the circles of radii $15$ and $20$,whose centers are $25$ units of distance apart,is

To increase milk yield,a cow is given:

If $\int \frac{x^2-1}{(x+1)^2 \sqrt{x(x^2+x+1)}} dx = A \tan^{-1}\left(\sqrt{\frac{x^2+x+1}{x}}\right) + C$,where $C$ is a constant,then $A$ equals to