Question

A man has to go 50 m due north, 40 m due east and 20 m due south to reach a field. (a) What distance he has to walk to reach the field ? (b) What is his displacement from his house to the field ?

Answer 1

a) Distance travelled = 50 + 40 + 20 = 110 m
b) AF = AB – BF = AB – DC = 50 – 20 = 30 M
His displacement is AD
AD = √  (AF² -DF²) = √  (30² - 40²) = 50m
In ΔAED tanθ = DE/AE = 30/40 = 3/4
θ = tan^–1 (3/4)
His displacement from his house to the field is 50 m, tan^–1 (3/4) north to east