I have made a mistake in the post "I Don't Know..." dated 12 Dec 2017, in the expression
\(P=\cfrac{8^3}{18}{\pi^2}∗f^2∗m_ac^2=1∗\cfrac{4}{3}\pi∗f^3∗m_ac^2\)
It should be
\(P=\cfrac{8^3}{18}{\pi^2}∗f^2∗m_ac^2=1∗\cfrac{3}{4\pi}∗f^3∗m_ac^2\)
where the \(RHS\) is divided by a spherical volume to obtain energy per unit volume. The expression leads to,
\(f=\cfrac{4*8^3}{3*18}\pi^3=1175.94 Hz\)
The previous result,
\(f=\cfrac{8^3}{24}\pi=67.02\,Hz\)
is not valid.
Sorry...
