Q28 of 56 Page 1

A student has to determine the focal length of a concave mirror by obtaining the image of a distant object on a screen. For getting the best result he should focus

To determine the focal length of a concave mirror by obtaining the image of a distant object on screen, the student should focus on a distant tree or an electric pole. A distant tree can be considered as infinity. So, when the light rays coming from infinity falls on a concave mirror, then the image will be formed at the focus of the mirror. Therefore, the focal length can also be calculated.

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