The natural frequency f (in s−1) of small radial oscillations of a gas bubble of equilibrium radius R in a liquid is believed to depend on the ambient pressure P and the density ρ of the liquid. Assuming a relation of the form f∝PaρbRc, which set of exponents (a,b,c) satisfies dimensional consistency?
a) (21,21,−1)
b) (1,−21,−1)
c) (21,−21,−1)
d) (21,−21,−21)