Question

If the rest energies of a positive sigma particle and a lambda particle are 1189.4 and 1115.7 Mev respectively, what is the difference in their masses in kilograms?

Answer 1

1.31022×10⁻³⁴ kg

Step-by-step explanation:

Difference in energies = 1189.4-1115.7 MeV = 73.7 MeV

Convert this energy to Joules

1 MeV = 1.6×10⁻¹⁹ J

73.7 MeV = 73.7×1.6×10⁻¹⁹ J = 117.92×10⁻¹⁹ J

c = Speed of light = 3×10⁸ m/s

From Einstein's equation

E = mc²

`m=(E)/(c^2)\\\Rightarrow m=(117.92* 10^(-19))/((3* 10^8)^2)\\\Rightarrow m=1.31022* 10^(-34)\ kg`

∴ Difference in their masses is 1.31022×10⁻³⁴ kg