If $x = \frac{1}{2} \left( \sqrt{3} + \frac{1}{\sqrt{3}} \right)$,then the value of $\frac{\sqrt{x^2 - 1}}{x - \sqrt{x^2 - 1}}$ is equal to

If the voltage between the terminals $A$ and $B$ is $17\,V$ and the Zener breakdown voltage is $9\,V$,then the potential across $R$ is....$V$

Which one of the following is a correct statement?

Match the following columns and select the correct option:

$(a)$ Placenta	$(i)$ Androgens
$(b)$ Zona pellucida	$(ii)$ Human Chorionic Gonadotropin $(hCG)$
$(c)$ Bulbourethral glands	$(iii)$ Layer of the ovum
$(d)$ Leydig cells	$(iv)$ Lubrication of the penis

$(a)\quad (b)\quad (c)\quad (d)$

The force required to move a body up a rough inclined plane is double the force required to prevent the body from sliding down the plane. If the angle of inclination of the plane is $60^{\circ}$,then the coefficient of friction is

Which one of the following sets correctly represents the increase in the paramagnetic property of the ions?