A Solid Conducting Sphere of Radius R_a Is Placed Concentrically

question 8

Multiple Choice

A solid conducting sphere of radius r_a is placed concentrically inside a conducting spherical shell of inner radius r_b1 and outer radius r_b2. The inner sphere carries a charge Q while the outer sphere does not carry any net charge. The electric field for r > r_b1 is

• A) -kQ/r².
• B) kQ/r².
• C) -2kQ/r.
• D) 2kQ/r.
• E) zero.

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Definitions:

Total Surplus

is the sum of consumer surplus and producer surplus, representing the overall economic benefit to society from trade or market activity.

Consumer Surplus

The split between the sum consumers would ideally pay for a good or service and the sum they actually end up paying.

Producer Surplus

The discrepancy between the price at which sellers are prepared to offer a product and the actual selling price they obtain.

Market Failure

The failure of a market to be efficient; when the individual pursuit of self-interest leads to bad results for society as a whole.