Two Lenses, One with a Focal Length F₁ = +20

question 48

Multiple Choice

Two lenses, one with a focal length f₁ = +20 cm and the other with a focal length f₂ = -20 cm, are on the same axis and 60 cm apart as shown. A real object is 40 cm to the left of the positive lens. The image formed by the negative lens is

• A) real and 10 cm from the negative lens.
• B) virtual and 10 cm from the negative lens.
• C) at infinity.
• D) virtual and 20 cm from the negative lens.
• E) None of these is correct.

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Definitions:

Well-structured Problems

Pertains to problems that have clearly defined parameters and solutions, often with known methods for solving them.

Routine Decision

Choices or judgments made during regular, day-to-day activities that are often repetitive and require minimal thought.

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A problem that lacks a clear path to a solution, often requiring creative or critical thinking for resolution.

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