7.9MeVα-particle scatters from a target material of atomic number 79. From the given data the estimated diameter of nuclei of the target material is (approximately) ____ m. [4πϵo1=9×109Nm2/C2 and electron charge =1.6×10−19C]
Held on 22 Jan 2026 · Verified 6 Jul 2026.
1.44×10−13
5.76×10−14
2.88×10−14
1.69×10−12
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