Question

Two equally charged particles, held `3.2xx10^(-3) m` apart, are released from rest. The initial accelerartion of the first particle is observed to be `7.0 m//s^(2)` and that of the secound to be `9.0 m//s^(2)`. If the mass of the first particle is `6.3xx10^(-7) kg`, what are (a) the mass of the secound particle adn (b) teh magnitude of the charge of each particle ?

Answer 1

Correct Answer - `= 4.9xx10^(-7) kg, q = 7.1xx10^(-11)C`
Here, `a_(1) = 7.0 m//s^(2), a_(2) = 9.0 m//s^(2)`,
`m_(1) = 6.3xx10^(-7) kg , m_(2) = ?`
As `F_(1) = F_(2)`
`:. m_(1) a_(1) = m_(2) a_(2)`
`m_(2) = (m_(1) a_(1))/(a_(2)) = (6.3xx10^(-7)xx7.0)/(9.0)`
`= 4.9xx10^(-7) kg`
As `F_(1) = F_(2) = (q_(1) q_(2))/(4pi in_(0) r^(2)) = m_(1) a_(1)`
`= 6.3xx10^(-7) xx7.0 = 44.1xx10^(-7)`
`:. (9xx10^(9) q^(2))/((3.2xx10^(-3))^(2)) = 44.1xx10^(-7)`
`:. q = 7.1xx10^(-11)C`