An object is placed 24 cm from a convex lens of focal length 15 cm. How far from the lens is the real image formed?

Answer and explanation

Correct answer: C. 40 cm

  1. Step 1: Lens formula: .
  2. Step 2: .
  3. Step 3: cm.
Answer
40 cm.
Why not the others: 9 cm: it subtracts the focal length from the object distance. 39 cm: it adds the distances. 120/13 cm: it uses instead of .

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