Delta-v (physics) such as determining the change in momentum (impulse), where :formula_4, where formula_5 is momentum and m is mass. Delta-v (physics) Delta comes as the 4th letter in the greek alphabets which is spell as 'D' in the english alphabets . In general physics, delta-"v" is simply a change in velocity. The Greek uppercase letter delta is the standard mathematical symbol to represent change in some quantity. Depending on the situation, delta-"v" can be either a spatial vector (Δv) or scalar (Δ"v"). In either case it is equal to the acceleration (vector or scalar) integrated over time: If acceleration is constant,
Product of group subsets "ST", then "ST" coincides with the semidirect product of "S" and "T". Finally, if both "S" and "T" are normal in "ST", then "ST" coincides with the direct product of "S" and "T". If "S" and "T" are subgroups whose intersection is the trivial subgroup (identity element) and additionally "ST" = "G", then "S" is called a complement of "T" and vice versa. By a (locally unambiguous) abuse of terminology, two subgroups that intersect only on the (otherwise obligatory) identity are sometimes called disjoint. A question that arises in the case of a non-trivial intersection between a normal subgroup "N"