If the dot product of two vectors (X and Y) is zero, then which of the following conditions is TRUE?
Correct answer: C. The vectors are orthogonal to each other
- A. Both vectors are opposite in direction
- B. Both vectors are parallel to each other
- C. The vectors are orthogonal to each other
- D. Either of the two vectors is a null vector
Explanation
The correct answer is that the vectors are orthogonal to each other. The dot product of two vectors is zero when the angle between them is 90 degrees, meaning they are perpendicular. Option A is incorrect because opposite vectors would have a negative dot product if they are not zero vectors. Option B is incorrect because parallel vectors (when not zero) have a non-zero dot product. Option D is incorrect because while a null vector would result in a zero dot product with any other vector, the question context suggests orthogonality.
Last updated
About Scalar Product
The scalar product of two vectors is A dot B equals AB cos theta, producing a scalar determined by their magnitudes and included angle. Applications include work done and projection of one vector on another, with perpendicular vectors giving zero and the scalar product distinguished from the vector product.
Practise Vectors and Equilibrium
431 free Vectors and Equilibrium MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.