Solve the Problem $\mathrm { I } ( t ) = 7 \cos ( 120 \pi t )$

question 203

Multiple Choice

Solve the problem.
-Suppose that a household appliance draws a current represented by the relation $\mathrm { I } ( t ) = 7 \cos ( 120 \pi t )$ , where $t$ is time measured in seconds. The power consumed by the appliance is $P = I ^ { 2 } R$ , where $R$ is a constant. Take $R$ to be 16 and graph the power in [0, 0.04, 0.01] by $[ - 200,2000,200 ]$ and use an identity to write the expression for the power in the form $\mathrm { P } = \mathrm { a } \cos ( \mathrm { k } \pi \mathrm { t } ) + \mathrm { d }$ , where $\mathrm { a }$ , $\mathrm { k }$ , and $\mathrm { d }$ are constants.

• A) \(\mathrm { P } = - 392 \cos ( 240 \pi \mathrm { t } ) + 392\) \([ 0,0.04,0.01 ]\) by \([ - 200,2000,200 ]\)
• B) \(\mathrm { P } = 392 \cos ( 120 \pi \mathrm { t } ) + 392\) \([ 0,0.04,0.01 ]\) by \([ - 200,2000,200 ]\)
• C) \(\mathrm { P } = 392 \cos ( 240 \pi \mathrm { t } ) + 392\) \([ 0,0.04,0.01 ]\) by \([ - 200,2000,200 ]\)
• D) \(P = 784 \cos ( 240 \pi t ) + 784\) \([ 0,0.04,0.01 ]\) by \([ - 200,2000,200 ]\)

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Definitions:

Net Profit

The amount of money a company earns after deducting all its expenses, taxes, and costs from its total revenue.

Variable Manufacturing Costs

Costs that fluctuate with the level of production, including direct materials, direct labor, and variable manufacturing overhead.

Direct Method

An accounting approach used to allocate service department costs directly to producing departments without considering other service departments.

Janitorial Department

A division within an organization responsible for maintaining cleanliness, hygiene, and sanitation within the premises.