NEET2018PhysicsMathematics in PhysicsActual
Assertion : If dot product and cross product of P and Q are zero, it implies that one of the vector P and Q must be null vector. Reason : A null vector is a vector of zero magnitude.
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion.
- BIf both assertion and reason are true but reason is not the correct explanation of assertion.
- CIf assertion is true but reason is false.
- DIf both assertion and reason are false.
Correct answer
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
Step-by-step solution
As per question, | A B |=| A B |=0 This is possible if either A=0 or B=0 . Magnitude of a null vector is zero.