A CD Player and Its Battery Together Do 500 KJ

question 107

Multiple Choice

A CD player and its battery together do 500 kJ of work .The battery also releases 250 kJ of energy as heat and the CD player releases 50 kJ as heat due to friction from spinning.What is the change in internal energy of the system,
With the system regarded as the battery and CD player together?

• A) +200 kJ
• B) -700 kJ
• C) -800 kJ
• D) -200 kJ
• E) -750 kJ

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Definitions:

Markup Percent

The percentage increase between the cost of a product and its selling price, indicating the gross margin.

Fireproof Safe

A secure storage unit designed to protect contents from fire damage up to certain temperatures or for a specified duration.

Cubic Inch

A unit of volume measurement in the Imperial and United States customary systems, equivalent to the volume of a cube with each side being one inch long.

Dollar Markup

The difference between the selling price of an item and its cost expressed in dollars, representing the retailer's gross profit.