A spherical dewdrop, when deformed slightly, oscillates about its equilibrium shape. The physically relevant variables to describe the frequency of this oscillation $f$ are its mass $M$, radius $R$ and a third variable $Q$, where $Q$ could be either the universal gravitational constant $G$ or the surface tension $S$. One must decide the relevant variable $Q$ and employ dimensional analysis to express $f$ as
$f=k M^x R^y Q^z$,
where $k$ is a dimensionless constant. Then

• Correct answer
  A

  $x=-1 / 2, y=0$ and $z=1 / 2$
• B

  $x=1 / 2, y=-3 / 2$ and $z=1 / 2$
• C

  $x=1 / 2, y=0$ and $z=-1 / 2$
• D

  $x=-1 / 2, y=-3 / 2$ and $z=1 / 2$

Hence, the correct answer is option: 'A'.