Question

12
If resultant of two unit vectors â and b is also a
unit vector, then magnitude of difference of
â and ô lise
(1) Zero 2
(2) 1
(3) V3
(4) VE
60B​

Answer 1

Explanation:

Q. THE RESULTANT OF TWO UNIT VECTOR IS UNIT VECTOR.FIND THE ANGLE BETWEEN TWO VECTOR.

ANS.

R^2= A^2+B^2-2ABCostheta.

Resultant and magnitud is unity: means A=1 ,B= 1 and R=1.

Then:

1= 1+1-2×1×1Cos theta.

1= 2- 2cos theta

-2cos theta=2-1 then

Cos theta = -1/2. that is 120°

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Thank you.