Question

Considering the relation between current $I$, voltage $V$ and resistance $R$, which of the following equations is/are TRUE?

• A. $V^2=I^2{R}^2$
• B. $R^{-2}=V^{-2}{I}^2$
• C. $V^2=R{I}^{-2}$
• D. $V^{-2}=R^2{I}^{-2}$

Answer 1

Answer: (A), (B)

The correct options are
A $V^2=I^2{R}^2$
B $R^{-2}=V^{-2}{I}^2$

From Ohm's law, the relation between current $I$, voltage $V$ and resistance $R$ is given simply as: $V=IR$----- (1)
$\therefore V^2=I^2{R}^2$.

From equation (1), $R=\frac{V}{I}=V{I}^{-1}$
$\Rightarrow R^{-1}=V^{-1}I$
$\Rightarrow R^{-2}=V^{-2}{I}^2$.