Question

If in an electric. Circuit voltage V = 21 + 5j and current I = 4i + 9j then power is equal to ​

Answer 1

Given: the voltage is $V=2i+5j$. The current is $I=4i+9j$.

To find: the power

Step-by-step method:

Step 1 of 2

The power is calculated by using the formula $P=VI$.

P is the power.

V is potential.

I is current.

The dot product of a vector is calculated as:

$(ai+bj).(ci+dj)=ac+bd$

Step 2 of 2

Power will be:

$P=(2i+5j).(4i+9j)\\P=2*4+5*9\\P=8+45\\P=53Watt$

The Power is equal to $53Watt$.