Question

The ratio of magnitude of electrostatic force and gravitational force for an electron and a proton is
A. `6.6xx10^(39)`
B. `2.4xx10^(39)`
C. `6.6xx10^(29)`
D. `2.4xx10^(29)`

Answer 1

Correct Answer - B
Here, for an electron and a proton
Electrostatic force, `|F_(e)|=1/(4piepsilon_(0))e^(2)/r^(2)`
Gravitational force, `|F_(g)|=(Gm_(e)m_(p))/r^(2)`
`therefore" "(|F_(e)|)/(|F_(g)|)=1/(4piepsilon_(0))e^(2)/(Gm_(e)m_(p))`
`=(9xx10^(9)xx(1.6xx10^(-19))^(2))/(6.67xx10^(-11)xx9xx10^(-31)xx1.66xx10^(-27))=2.4xx10^(39)`