How do I find the height of the image?

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SUMMARY

The discussion focuses on calculating the height of an image formed by a concave mirror. The object height is 1.80 cm, and it is positioned 19.7 cm from the mirror, which has a radius of curvature of 12.2 cm. The focal length is determined to be 6.1 cm, and the image distance calculated is 8.836 cm. The correct method to find the image height involves using the magnification formula, which relates the image height to the object height and the distances from the mirror.

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Homework Statement


A 1.80-cm-high object is situated 19.7 cm in front of a concave mirror that has a radius of curvature of 12.2 cm. Calculate (a) the location and (b) the height of the image.


Homework Equations


f=1/2R
1/image distance + 1/object distance = 1/f


The Attempt at a Solution


f=1/2(12.2) = 11.1
1/image distance + 1/19.7 = 1/6.1
image distance = 8.836 cm

then I thought to find the image height I'd just take 8.836 cm - 1.8 cm = 7.036 cm but this is incorrect.
 
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The ratio of image height to object height = the magnification will equal the ratio of distance from image over distance of the object to the mirror or lens.
 
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