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प्रश्न
Solve the numerical example.
Nuclear radius R has a dependence on the mass number (A) as R =1.3 × 10-16 A1/3 m. For a nucleus of mass number A = 125, obtain the order of magnitude of R expressed in the meter.
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उत्तर
R = 1.3 × 10-16 × A1/3 m
For A = 125
R = 1.3 × 10-16 × (125)1/3
= 1.3 × 10-16 × (53)1/3
= 1.3 × 10-16 × 5
= 6.5 × 10-16
= 0.65 × 10-15 m
∴ Order of magnitude = - 15
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