Question

the resultant of two vectors f and F acting at 90 degree is?.

Answer 1

Hi friend here is your answer.

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We know, cos90=0

So, Resultant=√(F^2+f^2) ans.

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Answer 2

Resultant vector = (a²+b²-2abcosx)^-2

When the angle between f and F is 90°
Resultant vector = f²+F² + 2fFcos90
=> F²+f² +0 (as cos90 =0)