Ma (F). 5. The note Ma (or the fourth note) is produced at the middle of the Fundamental Note and its octave. The note Ma is therefore produced at half the length of Sa 1 (C1 ) and Sa 2 (C2 ) or at 1/2 (36" + 18") = 1/2(54") = 27". In other words the note of the wire 27 inches or 27" of the executive part of the wire will give out the 4th note or Ma (F) and by rule (4) formula (B) the pitch or vibrations of Ma (F) are equal to 320. The formula (B) is : Vn = U X l/ln; Here U = 240, l= 36 and ln = 27. Vn = 240 X 36/27 = 320 = Vibrations of Ma. And formula (C) is :- ln = U X l/Vn ஃ ln = 240 Xl/320 = 3/4 l = 3/4 X 36or the length of Ma is 3/4 of the length of the F. N. and the Vibrations of Ma are 4/3 of the F.N. and it may be laid down :- 6. That the length of the wire of Ma (F) or the 4th note is 3/4 of that of the Fundamental Note and the Vibrations of Ma (F) are 3/4 of the Vibrations of the Fundamental Note Sa 1 (C1 ). Pa (G). 7. The fifth or Pa (G) note is produced on 1/3or 2/3of whole length of the wire. The former note is one octave higher than the latter. The length of the wire is 36". Therefore a length of 12" or 24" will give the fifth note Pa (G). But we want the length between 18" and 36" - the two limits of the octave. Therefore the length 24" is that which we require and it will give out the note Pa (G) Let us apply the formulae (B) and (C) to the case of Pa (G) Vn = U X l/ln .................................(B) Substitute the values U = 240, l= 36 and ln = 24 Vn = 240 X 36/24 = 360 = Vibrations of Pa (G) = U X 36/24 = 3/2U or the vibrations of Pa (G) are 3/2 of its Sa1 or F. N. and ln= U l/Vn .................................(C) ஃ ln = 240/360 X l = 2/3 l = 24. or the length of Pa is 2/3of its Sa 1 (C1 ) or F.N. These facts may be noted down under rule (8) below. 8. The length of the wire of Pa (G) or the fifth note is 2/3 of that of Sa 1 's (C1 ) wire and its vibrations or pitch is 3/2of that of Sa 1 (C1). Ri (D). 9. In the interval of a given octave Sa 1 (C1 ) with Pa (G) and Ma (F) with Sa 2 (C2 ) form perfect concords; it may be noted that Sa 1 (C1) with Ma (F) and Pa (G) with Sa 2 (C2 ), the inverted interval, form imperfect concords.
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