# Dictionary:Eötvös effect

(∂t’ v∂sh) The vertical component of a Coriolis acceleration observed when measuring gravity while the measuring instrument is in motion with respect to the Earth, as in dynamic gravity. The meter’s velocity over the surface adds vectorially to the velocity because of the Earth’s rotation, varying the centrifugal acceleration and hence the apparent gravitational attraction. The Eötvös correction E in mGal for a meter whose speed is V knots at an azimuth angle α and latitude ${\displaystyle \phi }$ is
${\displaystyle E=7.503V\cos {\phi }\sin {\alpha }+0.004154V^{2}}$
${\displaystyle dE=7.503V\cos {\phi }\cos {\alpha }d{\alpha }+(7.503\cos {\phi }\sin {\alpha }+0.00830V)dV}$