Four Waves Are Described by the Following Expressions, Where Distances

question 68

Multiple Choice

Four waves are described by the following expressions, where distances are measured in meters and times in seconds. I y = 0.12 cos(3x - 21t)
II y = 0.15 sin(6x + 42t)
III y = 0.13 cos(6x + 21t)
IV y = -0.23 sin(3x - 42t)
Which of these waves have the same period?

• A) I and III, and also II and IV
• B) I and IV, and also II and III
• C) I and II, and also III and IV
• D) All of them have the same period.
• E) They all have different periods.

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Definitions:

Production Increase

An increment in the amount of products manufactured by a company during a specified period.

Differential Cost

The difference in total cost that will result from selecting one alternative over another in decision-making.

Product Costs

Costs that are directly associated with the production of goods or services, including direct materials, direct labor, and manufacturing overhead.

Period Costs

Expenses that are not directly tied to the production of goods and are therefore expensed in the period they occur, such as selling and administrative expenses.