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Nucleus A has mass number 220 and binding energy per nucleon of 5.6 MeV. It splits into fragment B (mass number 104) and fragment C (mass number 116). The binding energy per nucleon in both B and C is 6.4 MeV. Find the energy Q released per fission.

1. 0.8 MeV
2. 275 MeV
3. 220 MeV
4. 176 MeV

Correct answer: 176 MeV

Solution

Total BE of A = 220 * 5.6 = 1232 MeV. Total BE of B + C = 220 * 6.4 = 1408 MeV. Q = 1408 - 1232 = 176 MeV.

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