Question

I = 30A and R = 30; what is V?



A. 900v
B.90v
C.10v
D.0.1v

Answer 1

`V = 900\; {\rm V}` for a resistor where
`I = 30\; {\rm A}` and
`R = 30\; {\rm \Omega}`.

Step-by-step explanation:

By Ohm's Law, if the electric resistance of a resistor is
`R` and the current going through that resistor is
`I`, the voltage across that resistor would be
`V = I\, R`.

Note that electric resistance is typically measured in Ohms, where
`1\; {\rm \Omega} = 1\; {\rm V \cdot A^(-1)}`.

Given that
`I = 30\; {\rm A}` and
`R = 30\; {\rm \Omega}` for the resistor in this question, apply the formula
`V = I\, R` to find the voltage
`V` across this resistor:

`\begin{aligned} V &= I\, R \\ &= 30\; {\rm A} * 30\; {\rm \Omega} \\ &= 30\; {\rm A} * 30\; {\rm V \cdot A^(-1)} \\ &= 900\; {\rm V} \end{aligned}`.