Physics · WORK, ENERGY AND POWER
हिन्दीIn the vector representation shown in the figure, vector \( \mathbf{B} \) is inclined at an angle \( \theta \) to vector \( \mathbf{A} \). Which expression correctly gives the scalar product \( \mathbf{A} \cdot \mathbf{B} \) in terms of the components and projections illustrated?
Correct answer · Option 1
\( A (B \cos\theta) = B (A \cos\theta) \)
Explanation
Geometrically, the dot product equals the magnitude of \( \mathbf{A} \) multiplied by the projection of \( \mathbf{B} \) onto \( \mathbf{A} \) (\( B\cos\theta \)), or equivalently magnitude of \( \mathbf{B} \) times projection of \( \mathbf{A} \) onto \( \mathbf{B} \) (\( A\cos\theta \)).