Approaches 45521

The observer lies on the ground at a distance of 20m from a hunting lodge 5m high.
A) At what angle of view does the posed see?
B) How much does the angle of view change if it approaches the sitting by 5m?

Correct answer:

A =  14.0362 °
C =  4.3987 °

Step-by-step explanation:

$$\begin{gathered} x=20\text{m} \\ y=5\text{m} \\ \tan A=y:x \\ A=\frac{180°}{\pi }\cdot \arctan (y/x)=\frac{180°}{\pi }\cdot \arctan (5/20)=14.0362^{\circ }=14°2^{\prime }10" \end{gathered}$$

$$\begin{gathered} x_2=x-5=20-5=15\text{m} \\ \tan B=y:x_2 \\ B=\frac{180°}{\pi }\cdot \arctan (y/x_2)=\frac{180°}{\pi }\cdot \arctan (5/15)\doteq 18.4349{}^{\circ } \\ C=B-A=18.4349-14.0362=4.3987^{\circ }=4°23^{\prime }55" \end{gathered}$$

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