MCQ
If a unit vector is represented by $0.5\hat{\text{i}}+0.8\hat{\text{j}}+\text{c}\hat{\text{k}},$ then the value of 'c' is:
- A$1$
- B$\sqrt{0.11}$
- C$\sqrt{0.01}$
- D$\sqrt{0.39}$
✓
Answer
- $\sqrt{0.11}$
Explanation:
Here, (0.5)2 + (0.8)2 + (c)2 = 1
or $\text{c}=\sqrt{0.11}$
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