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Figure 54
Answer the following.
The graph shows how the magnification of a spherical mirror varies with the image distance (in cm)…
The graph shows how the magnification $|m|$ of a spherical mirror varies with the image distance $|v|$ (in cm).
What is its focal length?
Answer
Answer
Official answer key20 cm
Final answer: 20 cm
From ISC 2025 Practice Physics, question 54(b).
Check your working with the Lens and mirror calculator: image distance, magnification and nature for any lens or mirror, with the ray diagram.