Question

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

Answer 1

Side of the square = 10m
Farmer walks along boundary
So, distance covered = Perimeter of square
Distance covered = 40m
Time taken = 40seconds

So, distance covered in 1 second = 1m

Now,
2 min 20 seconds = 140 seconds
So,
Distance covered in 140 sec = 140m
140m = 3.5 rounds
(since, one round = 40m so, 140 m = 3 rounds + half round)

Displacement will be equal to the diagonal of square. (since, the farmer will be half way at the end)
SO,
Displacement = length of diagonal
Now,
Length of diagonal =
$\sqrt{ {10}^{2} + {10}^{2} }$
By Pythagoras theorem
The diagonal is considered as the hypotenuse of the right triangle.

SO, DIAGONAL =
$\sqrt{200} = 10 \sqrt{2} \: m$
Therefore,
The displacement is equal to
$10 \sqrt{2} \: m$


Hope this will be helping you.

WARM REGARDS
Sahil khirwal.

Answer 2

Answer:

Side of the square = 10m

Farmer walks along boundary

So, distance covered = Perimeter of square

Distance covered = 40m

Time taken = 40seconds

So, distance covered in 1 second = 1m

Now,

2 min 20 seconds = 140 seconds

So,

Distance covered in 140 sec = 140m

140m = 3.5 rounds

(since, one round = 40m so, 140 m = 3 rounds + half round)

Displacement will be equal to the diagonal of square. (since, the farmer will be half way at the end)

SO,

Displacement = length of diagonal

Now,

Length of diagonal =

By Pythagoras theorem

The diagonal is considered as the hypotenuse of the right triangle.

SO, DIAGONAL =

Therefore,

The displacement is equal to

Explanation: