A 20-Kg Block of Aluminum at 50°C Is Dropped into 5

question 29

Multiple Choice

A 2.0-kg block of aluminum at 50°C is dropped into 5.0 kg of water at 20°C and the temperature is allowed to stabilize.What is the total change in entropy during this process,assuming no heat is exchanged with the environment? The specific heat of aluminum is 910 J/(kg • K) and the specific heat of water is 4190 J/(kg • K) .

• A) 8.2 J/K
• B) 10 J/K
• C) 3.3 × 10^-2 J/K
• D) 3.8 × 10^-3 J/K
• E) 2.4 × 10^-3 J/K

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Definitions:

Activity-Based Costing

A costing methodology that assigns manufacturing and non-manufacturing costs to products or services based on the activities needed to produce them.

Machine-Hours

A measure of the amount of time machines are used in the production process, often used as a basis for allocating manufacturing overhead.

Overhead Cost

Expenses related to the ongoing operation of a business that cannot be directly traced to a specific product or service, like rent, utilities, and insurance.

Activity-Based Costing

A method of costing that apportions overhead and indirect expenditures to products and services related to the activities they entail.