A) \[71.6{}^\circ \]
B) \[45{}^\circ \]
C) \[90{}^\circ \]
D) \[18.4{}^\circ \]
Correct Answer: D
Solution :
[d] \[\text{l}\,\,\text{=}\,\,{{\text{l}}_{\text{0}}}{{\cos }^{2}}\theta \] |
\[\Rightarrow \frac{{{\text{l}}_{\text{0}}}}{\text{10}}\,\,\text{=}\,\,{{\text{l}}_{\text{0}}}{{\cos }^{2}}\theta \] |
\[\Rightarrow \frac{1}{10}={{\cos }^{2}}\theta \] |
\[\Rightarrow \cos \theta =\frac{1}{\sqrt{10}}=0.316\] |
\[\Rightarrow \theta \approx 71.6{}^\circ \] |
\[\therefore \phi =90-\theta -71.6=18.4{}^\circ \] |
You need to login to perform this action.
You will be redirected in
3 sec