OnlineCBT
Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
हिन्दीGiven below are two statements: Statement I: Under space reflection (inversion of coordinate axes), the vector cross product \( \mathbf{a} \times \mathbf{b} \) changes sign. Statement II: The scalar dot product \( \mathbf{a} \cdot \mathbf{b} \) does not change sign under reflection of coordinate axes. In the light of the above statements, choose the most appropriate answer from the options given below:
Correct answer · Option 4
Statement I is incorrect but Statement II is correct.
Explanation
Statement I is incorrect because \( (-\mathbf{a}) \times (-\mathbf{b}) = \mathbf{a} \times \mathbf{b} \), so cross product does not change sign under reflection. Statement II is correct because \( (-\mathbf{a}) \cdot (-\mathbf{b}) = \mathbf{a} \cdot \mathbf{b} \).
