Q19 of 43 Page 85

The resultant of two vectors at angle 150° is 10 units and is perpendicular to one vector. The magnitude of the smaller vector is

Let A and B be the two given vectors

Ɵ = 150° is the angle between A and B


If C is the resultant vector, then:


...1


Also, it is given that the resultant is perpendicular to one of the given vectors. Let that given vector be A



Now, …2


Putting 2 in 1, we get:










Now, putting c = 10, Ɵ = 150° ()



So,


Hence, smaller vector is A = 20 units


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