When an object is located 43 cm to the left of a lens, the image is formed 17 cm to the right of the lens.?

When an object is located 43 cm to the left of a lens, the image is formed 17 cm to the right of the lens. What is the focal length of the lens?When an object is located 43 cm to the left of a lens, the image is formed 17 cm to the right of the lens.?
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1/i - 1/o = 1/f


i = image distance = + 17


o = object distance = - 43


1/f = 1/17 + 1/43 = [43+17]/(43*17) = 60/(43*17)


f = 43*17/60 = + 12.18 cm


focal length is +ve, so convex lens by sign convention