posted by nani .
a person moves 30m north, then 20m east and then 30(square root of two)m south west . His displacement from the original position is ?.
Draw 3 vectors from the origin:
20m @ 0 Deg.(East).
30m @ 90 Deg.(North).
30*sqrt2 @ (270-45)Deg.(Southwest).
X = Hor. = 20 + 30*sqrt2*cos225 = -10m.
Y = Ver. = 30 + 30*sqrt2*sin225 = 0.
D = sqrt(X^2+Y^2)
D = sqrt(100+0) = 10 m.
NOTE: sqrt = Square root.