  Zahn (1975) first put forward and calculated in detail the torque experienced
by stars in a close binary systems due to dynamical tides. His widely used
formula for stars with radiative envelopes and convective cores is expressed in
terms of the stellar radius, even though the torque is actually being applied
to the convective core at the core radius. This results in a large prefactor,
which is very sensitive to the global properties of the star, that multiplies
the torque. This large factor is compensated by a very small multiplicative
factor, $E_{2}$. Although this is mathematically accurate, depending on the
application this can lead to significant errors. The problem is even more
severe, since the calculation of $E_{2}$ itself is non-trivial, and different
authors have obtained inconsistent values of $E_{2}$. Moreover, many codes
(e.g. BSE, StarTrack, MESA) interpolate (and sometimes extrapolate) a fit of
$E_{2}$ values to the stellar mass, often in regimes where this is not sound
practice. We express the torque in an alternate form, cast in terms of
parameters at the envelope-core boundary and a dimensionless coefficient,
$\beta_{2}$. Previous attempts to express the torque in such a form are either
missing an important factor, which depends on the density profile of the star,
or are not easy to implement. We show that $\beta_{2}$ is almost independent of
the properties of the star and its value is approximately unity. Our formula
for the torque is simple to implement and avoids the difficulties associated
with the classic expression.
