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A security camera in a neighborhood bank is mounted on a wall 12 feetabove the floor. What angle of depression should be used if the camera is tobe directed to a spot 4 feet above the floorand 40 feet from the wall?

User David Alan Hjelle
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1 Answer

18 votes
18 votes

Explanation

We are given the following:

• A security camera is mounted on a wall 12 feet above the floor.

We are required to determine the angle of depression when the camera is directed to a spot 4 feet above the floor and 40 feet from the wall.

This can be represented diagrammatically as:

We can extract a triangle from the diagram above as follows:

From the right-angled triangle above, we have:


\begin{gathered} Opposite=8ft \\ Adjacent=40ft \end{gathered}

Finally, we can obtain the angle of depression as follows:


\begin{gathered} \tan\theta=(opposite)/(adjacent) \\ \tan\theta=(8)/(40)=0.2 \\ \tan\theta=0.2 \\ \theta=\tan^(-1)(0.2) \\ \theta\approx11.3\degree \end{gathered}

Hence, the angle of depression is 11.3°.

A security camera in a neighborhood bank is mounted on a wall 12 feetabove the floor-example-1
A security camera in a neighborhood bank is mounted on a wall 12 feetabove the floor-example-2
User Knoefel
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