Solve the Problem $V ( t ) = 160 \cos ( 120 \pi t )$

Multiple Choice

Solve the problem.

-Suppose that a hair dryer operates on a voltage that can be represented by the relation $V ( t ) = 160 \cos ( 120 \pi t )$ and that it draws a current represented by the relation $I ( t ) = 12 \cos ( 120 \pi t )$ , where $t$ is time measured in seconds. The power consumed by the appliance is P =VI. Graph th 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) $\mathrm { P } = 960 \cos ( 240 \pi \mathrm { t } ) + 960$
$[ 0,0.04,0.01 ]$ by $[ - 200,2000,200 ]$



B) $\mathrm { P } = 1920 \cos ( 240 \pi \mathrm { t } ) + 1920$
$[ 0,0.04,0.01 ]$ by $[ - 200,2000,200 ]$

C) $P = 960 \cos ( 120 \pi t ) + 960$
$[ 0,0.04,0.01 ]$ by $[ - 200,2000,200 ]$


D) $P = - 960 \cos ( 240 \pi t ) + 960$
$[ 0,0.04,0.01 ]$ by $[ - 200,2000,200 ]$