COMEDK · Maths · 33. Vector Algebra
The magnitude of the projection of the vector \(-\hat{\imath}+2 \hat{\jmath}-\hat{k}\) on the z -axis is
- A \(1\)
- B \(-\dfrac{1}{\sqrt{6}}\)
- C \(\dfrac{1}{\sqrt{6}}\)
- D \(2\)
Answer & Solution
Correct Answer
(A) \(1\)
Step-by-step Solution
Detailed explanation
Let the given vector be \(\vec{A} = -\hat{i} + 2\hat{j} - \hat{k}\). The z-axis is represented by the unit vector \(\hat{k}\). The projection of a vector \(\vec{A}\) on a vector \(\vec{B}\) is given by \(\dfrac{\vec{A} \cdot \vec{B}}{|\vec{B}|}\). Here, \(\vec{B} = \hat{k}\), so…
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