It is found that |A+B|=|A|. This necessarily implies,
A. B = 0
B. A, B are antiparallel
C. A, B are perpendicular
D. A.B ≤ 0
We have to identity statements which are always true. It is given that , it could be true in two conditions that is either , which means option (a) and (b) might true.
For forming a single condition we will multiply them, as either one of them is true it will uphold the necessary condition
We know (from previous equations)
Therefore their magnitude’s product will also be zero.
(This will always be true)
(Equality is true for B=0)
Above condition is always true
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Motion in two dimensions, in a plane can be studied by expressing position, velocity and acceleration as vectors in Cartesian co-ordinates A = Axî + Ayĵ where î and ĵ are unit vector along x and y directions, respectively and Ax and Ay are corresponding components of (Fig. 4.9). Motion can also be studied by expressing vectors in circular polar co-ordinates as A = Ar + Aɵ where = = cosθ î + sin θ ĵ and = − sin θ î +cos θ ĵ are unit vectors along direction in which ‘r’ and ‘θ ’ are increasing.
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