Question

a farmer moves along the boundary of a square field of side 10 m in 40 second what will be the magnitude of displacement of the farmer at the end of 2 minutes 20 second from his initial position

Answer 1

speed = 25 cm. / sec.

Time = 140 secs.

Distance = Speed × Time = 25 m. / sec. × 140 sec. = 25 m. × 140 = 3500 m. = 3 km. 500 m. = 3 is to 1 / 2 km.

Answer 2

Given,
One side of square=10m
Time taken to cover 10m=40s
Distance covered in 2mins 20s=2*60+20
=140s
140/40=3.5 rounds

From this, we came to know that the farmer took 3 rounds and then half of the round.
A_______________B
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C_______________D
Suppose he started from A and took 3.5 rounds and his final position is D
Each side=10m
Displacement=AD
(AD)^2=(AB)^2+(BD)^2
= 100+100=200
AD=√200=14.14 m Displacement

Hope it helps.....