Question

A farmer moves along the boundary of square field of side 10 m in 40s what will be the magnitude

Answer 1

Length of boundary = perimeter of that square = 4a = 4*10 = 40 m

Time taken = 40s

Magnitude of speed = 40/40 = 1 m/s

Answer 2

Correct Question :

A farmer moves along the boundary of a square field of side 10 m in 4o s. What will be the magnitude of displacement of the farmer at the end of 2 min 20 sec from his initial position ?

AnswEr:

Distance covered by farmer in 40 sec = 40 m that is perimeter of the square field.

If he completed 1 round in 40 sec then in 2 sec 20 minutes that is 140 s.

• He completes = $\tt\cancel\dfrac{140}{40}=3.5\:rounds$

↝ Thus, if he starts from point B and reaches at point D,

• Displacement, BD = length of diagonal

$\star$ $\underline\text{Diagonal\:of\:square:-}$

$= \tt \: side \: \sqrt{2} \\ \\ \tt = 10 \sqrt{2} \\ \\ \tt = 10 \times 1.414 = 14.14 \: m$