If f1 = 12 cm, f2 = -18 cm, find the maximum focal length of the combination.
Correct answer: A. 36 cm
- A. 36 cm
- B. 34 cm
- C. 32 cm
- D. 30 cm
Explanation
To find the maximum focal length of the combination, we use the formula 1/f = 1/f1 + 1/f2. Substituting the given values f1 = 12 cm and f2 = -18 cm, we get 1/f = 1/12 + 1/-18. Solving this equation gives us f = 36 cm. This means the maximum focal length of the combination is 36 cm. The other options are incorrect because they do not correctly apply the formula or contain calculation errors.
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