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A concave mirror is broken into two parts and these parts are separated by a distance if 1 cm. The focal length of the mirror is 10 cm. Find the location of images(in cm), formed by the 2 parts of the mirror. The object is midway between the two principal axes at a distance of 15 cm from P.
I don't know whether the principal axis of the mirror is parallel to the principal axis of the mirror below. How do we define the principal axis here? what will the location of the image be? thank you.
Best Answer
The 2 "half mirrors" separated by 1 cm is equivalent to 2 full mirrors whose principal axis' are at a distance of 1 cm from each other , with the object in between as shown in the figure.
From the figure, we can say that the object distance are the same for the 2 mirrors. The only thing different will be the image heights, whose direction will be opposite of each other and the magnitudes will be the same.
Using the mirror formula, we get the images will be formed at a distance 30 cm in front of the mirror and at a height of 2 cm on either sides of the original principle axis.