A body ' A ' travel with velocity u → due east and another body B moves with velocity v → due west. What is the relative velocity of B w.r. to A ?

When two bodies moves opposite to each other, its relative velocity will be the summation of the two velocities. Therefore, relative velocity of B w.r.t. A = u → + v → .

Two bodies A and B are moving with velocities u → and v → at angle θ . Give the expression for relative velocity of B w.r. to A .

In this question we have to use the concept of relative velocity. Hence, following will be the correct answer. Two bodies A and B are moving with velocities u → and v → at angle θ . The expression for relative velocity of B w.r. to A is given by :- V B A → = V B → - V A → m a g n i t u d e i s g i v e n b y V B A → = V B → 2 + V A → 2 - 2 V B → V A → cos θ D I r e c t i o n i s g i v e n b y α = tan - 1 V A → sin θ V B → - V A → cos θ w h e r e V B A → = v e l o c i t y o f B w . r . t . A V B → = v e l o c i t y o f B V A → = v e l o c i t y o f A α = a n g l e b e t w e e n r e s u l tan t v e c t o r a n d v e c t o r V B →