Question

"Technician A says that Ohm's law can be used to determine circuit current flow if total circuit resistance and total voltage are known. Technician B says that Ohm's law can be used to calculate the unknown resistance of a load in a circuit if total current and source voltage are known. Which technician is correct?

Answer 1

Answer:

Both Technicians are correct.

Explanation:

Remember that Ohm's Law its a relationship between Voltage (E), Current (I) and Resistance (R) in an electrical circuit. This relationship is defined by the following equation:

$E=I*R$

Each one of the letters could be called a variable. Now, also remember that the number of equations you have is equal to the number of variables unknown you could have.

In Ohm's Law you have 3 variables (E,I,R) and 1 equation. It means that you need to know 2 variables (Whatever 2 variables) to know the third.

Technician A says, in other words, that could calculate the Circuit current flow (I) knowing total circuit resistance (R) and total voltage (E). Note that Technician A knows 2 to 3 variables, then it's possible to use Ohm's Law with the following equation:

$I=\frac{E}{R}$

Technician B says, in other words, that could determine the unknown resistance (R) knowing total current (I) and source voltage (E). Once again, note that Technician B knows 2 to 3 variables, then it's possible to use Ohm's Law with the following equation:

$R=\frac{E}{I}$

It is concluded that both technicians are right.