Two sphereical bodies, each of mass 50 kg, are placed at a separation of 20 cm. Equal charges are placed on the bodies and it is found that the force of Coulomb repulsion equals the grativational attraction in magnitude. Find the magnitude of the charge placed on either body.

Answer

A, C, D

Explanation

given, Mass = 50 kg,
`r= 20 cm = 0.2 m`
We know, `F_G= G (m_1 m_2)/r^2 `
`=(67x10^-11xx2500)/0.04`
Coulomb's force,
`F_c= 1/ (4pi_epsilon_0) (q_1 q_2)/r^2`
`=9xx10^9 a^2/ 0.04`
Since `F_G=F_c`
`rarr (6.7 xx10^-11xx 2500)/0.04 = (9xx10^0xxq^2)/0.04`
`rarr q^2 (6.7xx10^-11xx2500)/(9xx10^9)`
`= (9xx10^9)/0.04 = 1809xx10^-18`
` q= sqrt( 18.09xx10^-18)`
`4.3x10^-9C`.