Question

A farmer moves along the boundary of a square field of side 10 m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 min 20 s from its initial position?

Answer 1

Total time = 2 min 20 s = (2 × 60 s + 20 s) = 140 s

Distance covered in 40 s = 4 × 10 = 40 m

So, Distance covered in 140 s = 40 m × 140 s/ 40 s = 140 m

Now, 140 m = 3 × 40 m + 20 m

So, at the end of 2 min 20 s, the farmer will complete 3 rounds and he will be at a distance of 20 m (at point C) from the start (point A).

Thus, Displacement of the farmer = Length of AC = 10√2m = 14.1 m