A Cup of Coffee Is Enclosed on All Sides in an Insulated

question 32

Multiple Choice

A cup of coffee is enclosed on all sides in an insulated container 1/2 cm thick in the shape of a cube 10 cm on a side. The temperature of the coffee is 95°C, and the temperature of the surroundings is 21°C. Find the rate of heat loss (in J/s) due to conduction if the thermal conductivity of the cup is 2 × 10⁻⁴ cal/s⋅cm⋅°C.

• A)62
• B)74
• C)230
• D)160
• E)12

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Definitions:

Free Markets

Economic systems where prices for goods and services are determined by the open market and consumers, with minimal government intervention.

Opportunity Costs

The cost of foregone alternatives, or what is given up to engage in one activity instead of another.

Efficiency

The extent to which resources are used optimally to achieve a specific outcome with minimal waste.

Incentives

Factors, usually financial or material rewards, that motivate individuals or firms to act in a certain way.