Answer:
So the answer is the first one
E = 8.5 x 10 ⁻⁷ J
Explanation:
Given:
r₁ = 8 mm , r₂ = 11 mm , h = 152 m
ε₀ = 8.85 x 10⁻¹² N * m² / C²
C = Q / V
C = 2π * h * ε₀ / ln ( r₂ / r₁ )
C = [ 2π * 152 m * 8.85 x 10⁻¹² N * m² / C² ] / [ ln ( 11 mm / 8mm ) ]
C = 2.654 x 10⁻⁸ F
C = 26.54 nF
Now to determine the energy Emf
E = ¹/₂ * C * V²
E = ¹/₂ * 26.54 nF * 8²V
E = 8.5 x 10 ⁻⁷ J