The number of charge drifts are 3.35 X 10⁻⁷C
Explanation:
Given:
Potential difference, V = 3 nV = 3 X 10⁻⁹m
Length of wire, L = 2 cm = 0.02 m
Radius of the wire, r = 2 mm = 2 X 10⁻³m
Cross section, 3 ms
charge drifts, q = ?
We know,
the charge drifts through the copper wire is given by
q = iΔt
where Δt = 3 X 10⁻³s
and i = [tex]\frac{V}{R}[/tex]
where R is the resistance
R = [tex]\frac{pL}{r^{2} \pi }[/tex]
ρ is the resistivity of the copper wire = 1.69 X 10⁻⁸Ωm
So, i = [tex]\frac{\pi(r)^{2}V }{pL}[/tex]
q = [tex]\frac{\pi(r^{2} )Vt }{pL}[/tex]
Substituting the values,
q = 3.14 X (0.02)² X 3 X 10⁻⁹ X 3 X 10⁻³ / 1.69 X 10⁻⁸ X 0.02
q = 3.35 X 10⁻⁷C
Therefore, the number of charge drifts are 3.35 X 10⁻⁷C
