This is the same as if the point of suspension were fixed, and a horizontal disturbing force mgf/l were to act on the bob.
[H,K, (MgF)13Mg3A1(S104)3 The water which is present in muscovite.
Clarke (1889-1893) supposes them to be substitution derivatives of normal aluminium orthosilicate A14(S104)3, in which part of the aluminium is replaced by alkalis, magnesium, iron and the univalent groups (MgF), (A1F2),(AlO), (MgOH); an excess of silica is explained by the isomorphous replacement of H 4 SiO 4 by the acid H4S130s.
How would you define mgf? Add your definition here.