Dot product of two non-zero vectors is zero ( a . b = 0) when angle between them is be:
Correct answer: D. 90°
- A. 30°
- B. 45°
- C. 60°
- D. 90°
Explanation
When the dot product of two non-zero vectors is zero (a · b = 0), it means that the angle between them is 90 degrees. The dot product of two vectors, a and b, is calculated as the product of their magnitudes multiplied by the cosine of the angle between them: a · b = |a| * |b| * cos(θ) If the dot product is zero, it means that the cosine of the angle, cos(θ), is also zero. The only angle for which the cosine is zero is 90 degrees. So, when the dot product of two non-zero vectors is zero, it indicates that the angle between them is indeed 90 degrees.
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Vectors have magnitude and direction, unlike scalars, and are combined by head-to-tail or parallelogram methods. Work covers rectangular components, equilibrium when the resultant force is zero, the scalar product for work and projections, and the vector product for torque and cross-product direction using the right-hand rule.
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