Answer:
1.11×10¹⁹ electrons
Explanation:
The formula for electric energy is given as,
E = QV ................. Equation 1
Where E = Electric Energy, Q = charge, V = Voltage.
Make Q the subject of the equation
Q = E/V............... Equation 2
Given: E = 8 W, V = 4.5 V.
Substitute into equation 2
Q = 8/4.5
Q = 1.778 C
using,
n = Q/e............ Equation 3
Where n = number of electron, e = Charge of one electron.
Given: e = 1.6×10⁻¹⁹ C
Substitute into equation 3
n = 1.778/1.6×10⁻¹⁹
n = 1.11×10¹⁹ electrons