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4. A farmer moves along the boundary of a square field of side 10
what will be the magnitude of displacement of the farmer at the
minutes and 20 sec?
-zian with a
Answers
Answer:
Here, Side of the given square field = 10m
so, perimeter of a square = 4*side = 10 m * 4 = 40 m
Farmer takes 40 s to move along the boundary.
Displacement after 2 minutes 20 s = 2 * 60 s + 20 s = 140 seconds
since in 40 s farmer moves 40 m
Therefore, in 1s the distance covered by farmer = 40 / 40 m = 1m
Therefore, in 140s distance covered by farmer = 1 � 140 m = 140 m. Now, number of rotation to cover 140 along the boundary= Total Distance / Perimeter
= 140 m / 40 m = 3.5 round
Thus, after 3.5 round farmer will at point C of the field.
Thus, after 2 min 20 seconds the displacement of farmer will be equal to 14.14 m north east from initial position.
Answer:
Given side of square =10m, thus perimeter P=40m
Time taken to cover the boundary of 40 m =40 s
Thus in 1 second, the farmer covers a distance of 1 m
Now distance covered by the farmer in 2 min 20 seconds = 1×140=140m.
Now the total number of rotation the farmer makes to cover a distance of 140m
meters = total distance / Perimeter.
= 3.5
At this point, the farmer is at a point say B from the origin O
Thus the displacement s = √10² +10 ²
From Pythagoras theorem.
s=10 √2
=14.14m