In Cavendish.s experiment , let each small mass be 20g and each large mass be 5 kg. The rod connecting the small masses is 50 cm long. while the small and the large speres are separated by 10.0 cm . The torsion constant is 4.8xx10^(-8)kgm^(2)s^(-2)and the resulting angular deflection is 0.4^(@)Calculate the value of universal gravitational constant G from this data.

In Cavendish.s experiment , let each small mass be 20g and each large

1.	In Cavendish.s experiment , let each small mass be 20g and each large mass be 5 kg. The rod connecting the small masses is 50 cm long. while the small and the large speres are separated by 10.0 cm . The torsion constant is 4.8xx10^(-8)kgm^(2)s^(-2)and the resulting angular deflection is 0.4^(@)Calculate the value of universal gravitational constant G from this data.
Answer» Solution :Here, m = 20g = 0.02 kg , M = 5 kg R = 10 cm = 0.1 m , 1 = 50 cm = 0.5 m `(theta=0.4^(0)=0.4^(0))(2pi//360^(0))=0.007` rad, `k= 4.8xx10^(-8) "kgm"^(2)s^(-2)` Thus, from `G = (kthetar^2)/(Mml)` on substitution `G = 6.72xx10^(-11) Nm^(2)kg^(-2)`