Q32. A compound microscope has fₒ = 2 cm, fₑ = 5 cm and tube length 27 cm. The final image is at infinity. Total angular magnification magnitude (D = 25 cm) is:
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Question

Q32. A compound microscope has fₒ = 2 cm, fₑ = 5 cm and tube length 27 cm. The final image is at infinity. Total angular magnification magnitude (D = 25 cm) is:

G1 Physics · Accepted Answer

GIVEN: Compound microscope fₒ = 2 cm, fₑ = 5 cm, L = 27 cm, D = 25 cm; final image at ∞. Step 1: Intermediate objective image must be 5 cm in front of eyepiece. Step 2: Objective image distance vₒ = L − fₑ = 27 − 5 = 22 cm. Step 3: Exact objective magnification magnitude |mₒ| = vₒ/fₒ − 1 = 22/2 − 1 = 11 − 1 = 10. Step 4: Eyepiece magnification mₑ = D/fₑ = 25/5 = 5. Step 5: Total magnitude |M| = 10 × 5 = 50. FINAL ANSWER: 50. Option B.