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3 years ago

A runner traveled 15 kilometers north then backtracked 11 kilometers south before stopping. His resultant displacement was

Physics

2 answers:

Vanyuwa [196]3 years ago

5 0

displacement is 4 km in north direction.

Explanation:

we are given

A runner traveled 15 kilometers north first

then backtracked 11 kilometers south

we have to find displacement=d=?

assume that east side represents +ve x- axis(horizontal)

and

north represent +ve y - axis (vertical)

we can take x-axis (horizontal) as i

and y-axis (vertical) as j.

Displacement = 15 j -11 j = 4 km north

Serhud [2]3 years ago

4 0

<u>Answer:</u>

Resultant displacement is 4 km north.

<u>Explanation:</u>

Let east represents positive x- axis and north represent positive y - axis. Horizontal component is i and vertical component is j.

A runner traveled 15 kilometers north then backtracked 11 kilometers south before stopping,

So initial displacement, 15 kilometers north = 15 j km

Second displacement, 11 kilometers south = -11 j km

Total displacement = 15 j -11 j = 4 j km

Total displacement is 4 km north.

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