Answer:
= 15 m/s
Explanation:
Considering right side(west) as positive x-axis and south as negative y-axis.
velocity of boat in still water [tex]v_b=12\hat{i}[/tex]
velocity of stream [tex]v_s=-9\hat{j}[/tex]
now relative velocity of boat w.r.t. stream [tex]v_{b/s}=12\hat{i}+9\hat{j}[/tex]
this velocity with which ac distance will be covered.
therefore magnitude of [tex]v_{b/s} =\sqrt{12^2+9^2}[/tex]
= 15 m/s
