the resultant of 2 vectors u and v is perpendicular to u and its magnitude is equal to half of v find the angle between u and v?

**Solution**:

Here,resultant of u and v is R. Resolving v into two rectangular components,we have vcos and vsin.

As per question,

R=vcos

and R=v/2

So v/2=v cos

cos =1/2=>=

Hence angle between u and v=

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