Answer:
Step-by-step explanation:
Electric field at distance r from the axis of a charged cylinder
= λ / 2πε₀ r
where λ is linear charge density
4.9 x 10⁴ = λ / (2π x 8.85 x 10⁻¹² x .25)
λ = 4.9 x 10⁴ x2π x 8.85 x 10⁻¹² x .25
= 68.08 x 10⁻⁸ C
Length of cylinder = 4.2 m
Total charge on the cylinder
= 4.2 x 68.08 x 10⁻⁸ C
= 285.95x 10⁻⁸ C