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Answer the following.
A student is performing an experiment to determine focal length of a convex lens by using lens…
A student is performing an experiment to determine focal length of a convex lens by using lens formula i.e., by no parallax method. The examiner gives some instructions to the student. The student responds to each instruction as per her understanding of the experiment.
State whether the student's response is correct or incorrect. Give a reason for your answer.
EXAMINER: Write the relation between the optical power ($P$) and the focal length ($f$) of the convex lens.
STUDENT writes $P = 2f$.
Answer
Answer
AIIncorrect. The optical power of a lens is the reciprocal of its focal length, $P = \dfrac{1}{f}$ (with $f$ in metres), not $P = 2f$.
From ISC 2024 Physics Paper 1, question 15(iii).
Check your working with the Lens and mirror calculator: image distance, magnification and nature for any lens or mirror, with the ray diagram.