Respuesta :
Answer:
1.39 × 10⁻¹³ electrons were transferred
Explanation:
Given:
Charge on electroscope = - 2.0 μC
charge on finger = 2.7 μC
Now,
The net charge when in contact
= Charge on electroscope + charge on finger
or
The net charge when in contact = - 2.0 μC + 2.7 μC = 0.7 μC
Also,
Charge on the electroscope and the finger is same
thus,
The charge on the electroscope = [tex]\frac{\textup{Net charge}}{\textup{2}}[/tex]
or
The charge on the electroscope = [tex]\frac{0.7}{\textup{2}}[/tex]
or
The charge on the electroscope = 0.35 μC
Now,
The change in charge on the electroscope
= Final charge - Initial charge on the electroscope
= 0.35 μC - (- 2.0 μC)
or
The change in charge on the electroscope = 2.35 μC
also,
Charge = Number of electrons × Charge on an electron
or
2.35 μC = Number of electron × 1.69 × 10⁻¹⁹ C
or
2.35 × 10⁻⁶ C = Number of electron × 1.69 × 10⁻¹⁹ C
or
Number of electron = [tex]\frac{\textup{2.35\times10^{-6}}}{\textup{1.69\times10^{-19}}}[/tex]
or
Number of electron = 1.39 × 10⁻¹³ electrons were transferred.
