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Here is my question: Take an object A and another object B, both of the same size.

B is rigid (static) but A is mobile . If I took A further away from observer then it goes on shrinking. Why is that the case ??

Qmechanic
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Prabhat
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1 Answers1

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If I understand your question correctly, you wonder why when an object is far away it seems smaller?

This can be explained with basic trigonometry.

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In this triangle, let say your object A has a height given by the distance $h=HF$

If we call the distance between your eyes and the object $d=EF$

Then the height that you see is linked to the angle at the corner $E$. Let's call that angle $\theta$.

Then, you have $\theta=arctan(h/d)$

As d gets bigger, the angle $\theta$ will decrease and it will seem that the objects is shrinking.

Albert Beton
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