Q.Write two different vectors having same magnitude.
The key idea is that magnitude depends only on the squares of the components, not on their signs or order. So two vectors like and both have magnitude .
The magnitude (or length) of a vector is given by . This formula depends only on the squares of the components. That means if you change the sign of any component, or rearrange the components, the sum of squares stays the same — as long as the set of absolute values is unchanged.
So to get two different vectors with the same magnitude, you can:
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Flip signs: Take . Its magnitude is . Now take . Its magnitude is . They are different vectors (point in opposite directions along the x-axis) but have the same length.
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Permute components: Another pair: and . Both have magnitude because the sum of squares is in both cases.
In 2D, a classic example is and — both have magnitude . Or even and — both have magnitude , but are perpendicular.
A common mistake is to think that if two vectors have the same magnitude, they must be equal or opposites. Not true — as the permutation example shows, they can be completely unrelated in direction.
Two such vectors are and , both with magnitude .
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