Question

a man goes 10m towards north then 20 m towards east then the displacement is

Answer 1

This answer can be solved using the Pythagoras theorem.

 So, the formula for displacement will be square root of 10 to the power two, added to square root of 20 to the power 2.

The answer will be square root of 500.

And so, finally the displacement is 22.36.

Answer 2

Given:

man goes 10 m towards north

again it goes towards east 20m.

To Find:

Find the displacement of the journey.

Solution:

man goes 10 m towards north ,

means if he starts from A then he has to go upwards straight to B to reach north, draw a line AB of length of 10 m.

again it goes towards east 20m.

means he again goes towards his east so he will turn left and go straight to C, draw a line joining B and C of 20 m.

as it is clear from the diagram that the displacement is AC,

join AC,

Find AC by applying pythagoras theorem in triangle ABC

AB² + BC² = AC²

10² + 20² = AC²

100 + 400 = AC²

500 = AC²

AC = √500

    =10√5

Hence the displacement of the journey is 10√5.