Final answer:
To find the position, nature, and size of an image formed by a concave mirror, use the mirror formula and magnification formula.
Step-by-step explanation:
To find the position, nature, and size of the image formed by a concave mirror, we can use the mirror formula: 1/f = 1/v - 1/u, where 'f' is the focal length, 'v' is the image distance, and 'u' is the object distance. In this case, the radius of curvature is given as 40 cm, so the focal length is half of that, which is 20 cm.
Plugging in the values, we get: 1/20 = 1/v - 1/100. Solving this equation will give us the image distance 'v'.
Based on the value of 'v', we can determine the nature of the image. If 'v' is positive, the image is real, and if 'v' is negative, the image is virtual. Finally, to find the size of the image, we can use the magnification formula: m = -v/u, where 'm' is the magnification, 'v' is the image distance, and 'u' is the object distance.
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