1.

The electrostatic attracting froce on a small sphere of charge `0.2muC` due to another small sphere of charge `-0.4muC` in air is 0.4N. The distance between the two spheres isA. `43.2xx10^(-6)m`B. `42.4xx10^(-3)m`C. `18.1xx10^(-3)m`D. `19.2xx10^(-6)m`

Answer» Correct Answer - B
Here, `q_(1)=0.2muC=0.2xx10^(-6)C`
`q_(2)=-0.4muC=-0.4xx10^(-6)C,F=-0.4N`
`As" "F=(q_(1)q_(2))/(4piepsilon_(0)r^(2)`
`therefore" "r^(2)=(q_(1)q_(2))/(4piepsilon_(0)F)=(0.2xx10^(-6)xx0.4xx10^(-6)xx9xx10^(9))/0.4`
`=1.8xx10^(-3)`
`therefore" "r=(1.8xx10^(-3))^(1//2)=0.0424m=42.4xx10^(-3)m`


Discussion

No Comment Found

Related InterviewSolutions