Question

A person facing north walks 3km turn left and walk 4km again walks 3km after turning right then turns right and 12km what is the displacement from the starting point and which direction he is facing ?
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Answer 1

Here is ur answer mate

Since a person is moving towards North for 3km

• Direction of movement - North

therefore ↑North - 3km

Now the person turns to walk 4km further

• Direction of movement - West

therefore ↑North - 3km

and ←West - 4km

Now the person walks 3km after turning right

• Direction of movement - North

therefore ↑North - 3km + 3km = 6km

and ←West - 4km

In the end the person turns right again and moves forward the 12km in East direction

• Direction of movement - East (opposite to West)

Therefore ↑North - 6km

and ←West - (4km - 12km) = -8km

Here we get West direction in negative

therefore we will replace it by East and -8km by its additive inverse i.e 8km

Therefore ↑North - 6km

→ East - 8km

Here a formation of a right triangle can be observed....

Where 8km and 6m are lengths of its legs

Therefore by Applying Pythagoras theorem

(Displacement)² = (Northen Displacement)² + (Eastern Displacement)²

or (Displacement)² = (6km)² + (8km)²

= 36km² + 64km²

= 100km²

or Displacement = √(100km²)

= 10km