VECTOR

VECTOR Unit vector  Polygon Law  Parallelogram Law R2 -; P2 + Q2 + 2 PQ cos  If A and B are in some direction, then |R| = A + B. If magnitude of A and B is the same, then |R| = 2 A cos /2. Triangular law |R| =  Tan  =  Rmax = | P + Q |, if  = 0 Rmax = |P -; Q |, if  = 1800  Vector addition follows Commutative law  Associative law =  Distributive law  If then  Subtraction of vectors Component of a vector is a scalar  = tan-;1  If and are two vectors and q is angle between them, . and are two vectors with an angle q between them . If and are two vectors acting at a point and a parallelogram is constructed with those two vectors as adjacent sides, then diagonals of that parallelogram are given by also 2(A2 + B2) = d12 + d22. Area and of the parallelogram = (1/2) .   Lami's Theorem  Relative velocity  Change in velocity  Average acceleration  Time taken to cross the river T =  To cross the river in shortest time t =