Question

A person moves 3km east then 2km north then 3.5km east.calculate its displacement and distance covered

Answer 1

3km + 2km + 3.5km = 8.5km..distance

Displacement.... is in a (reverse Z)

Answer 2

Let AB be d1 = 3km

Let BC be d2 = 2km

Let CD be d3 = 3.5 km

Total distance = 3 + 2 + 3.5

= 8km

Now, Draw a line DE perpendicular on AE and parallel and equal to BC.

So, DE = 2km

AE = 3+3.5 km

= 6.5 km.

In triangle ADE by Pythagoras theorem

AE^2 = AE^2 + DE^2

= 6.5^2 + 2^2

= 42.25 + 4

AE^2 = 46.25

AE = 6.8007 km

So, Distance = 8.5 km

Displacement = 6.8007 km