A Cylindrical Capacitor Is Made of Two Thin-Walled Concentric Cylinders

question 29

Multiple Choice

A cylindrical capacitor is made of two thin-walled concentric cylinders.The inner cylinder has radius r₁ = 4.0 mm,and the outer one a radius r₂ = 8.0 mm.The common length of the cylinders is L = 150 m. What is the potential energy stored in this capacitor when a potential difference 4.0 V is applied between the inner and outer cylinder? (k = 1/4πε₀ = 8.99 × 10⁹ N • m²/C²)

• A) 9.6 × 10^-8 J
• B) 1.3 × 10^-8 J
• C) 6.3 × 10^-8 J
• D) 0.34 × 10^-8 J
• E) 4.6 × 10^-8 J

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Definitions:

Marginal Cost

The outlay involved in the creation of an additional unit of a good or service.

Pareto Efficient

An economic state where resources are allocated in a way that it is impossible to make any one individual better off without making at least one individual worse off.

Efficiency

A measure of how well resources are used to achieve a goal, maximizing output from given inputs without waste.

Equity

The concept of fairness or justice, often discussed in the distribution of wealth, or the ownership interest in a firm.