A person moves `30 m` north, then `30 m est, then 30sqrt(2)` south-west. His diaplacement from the original position is

Options

A. ` 14 m South- West
B. (b) ` 28 m south
C. (c ) ` 10 m West
D. ` 15 m` East

Answer

C

Explanation

Resolving displacement ` 30 sqrt 2 m` South West in two rectangular components. We have
` 30 sqrt 2 cos 45^@= 30 sqrt 2 xx 1/(sqrt 2) = 30 m`
towards South
` and ` 30 sqrt 2 sin 45^@ = 30 sqrt 2 xx 1/( sqrt 2) = 30 m`
the resultant of ` 30 m` North will neutrilise the displacement of `30 m` South. Hence, the effective displacement is the resultant of ` 30 m` West and ` 20 m` East `= 10 m` West.