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$1$
- ✓$\sqrt{0.11}$
- C$\sqrt{0.01}$
- D$\sqrt{0.39}$
✓
Answer
Correct option: B.
$\sqrt{0.11}$
Here,$(0.5)^2 + (0.8)^2 + (c)^2 = 1$
or $\text{c}=\sqrt{0.11}$
or $\text{c}=\sqrt{0.11}$
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