The magnitude of i^. (j^ x k^) is________________?
Correct answer: B. 1
- A. 0
- B. 1
- C. -1
- D. i^
Explanation
Using the unit-vector cross-product rule, j × k = i. Hence i · (j × k) = i · i = 1, because the dot product of a unit vector with itself is 1. Option a would result from incorrectly treating perpendicular vectors in the original expression as making the whole triple product zero.
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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.
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