Answer:
(a) electrons being added.
(b) 7.5 × 10¹⁰
Explanation:
(a)
The plastic rod acquires a charge of -12 nC which means it contains more negative charge.
Thu, the electrons have been added to the rod. Removing protons are very difficult as they are in the nucleus and are bind by nuclear forces. Thus, by rubbing, electrons are transferred and thus the rod become negatively charged which means that the electrons being added.
(b)
The total charge = -12 nC
Also,
1 nC = 10⁻⁹ C
So,
Charge = -12 × 10⁻⁹ C
Charge on electron = -1.6 × 10⁻¹⁹ C
So, number of electrons transferred = -12 × 10⁻⁹ C / -1.6 × 10⁻¹⁹ C = 7.5 × 10¹⁰
