Question

Find the current that flows through a $115\;\Omega $ resistor when there is a $95.0\;{\rm{V}}$ potential difference across the resistor.

Answer 1

Hint: In the solution, Ohm’s law is employed to find the current passing through the circuit. Conductors are good at conducting electricity. The current passing through a conductor is related with the potential.

Complete step by step answer:
Given is the resistor with a resistance of $115\;\Omega $ at a potential difference of $95.0\;{\rm{V}}$.
Let us suppose that the resistor is at constant temperature. For finding the relationship between voltage, current and resistance, Ohm’s law can be employed. According to Ohm’s law, the potential difference across a conductor is directly proportional to the current flowing through it. This can be mathematically represented as,
$
V \propto I\\
V = IR
$
Here, $V$ is the potential difference, $I$ is the current passing, and $R$ is called the resistance, which is being offered to the varying current. This law is applicable assuming that all the physical conditions and the temperature is remaining constant.
From the above equation, we can express current in terms of voltage and resistance as,
$I = \dfrac{V}{R}$
Thus substituting $115\;\Omega $ for , and $95.0\;{\rm{V}}$ for $V$, we have,
$
I = \dfrac{{95.0\;{\rm{V}}}}{{115\;\Omega }}\\
\therefore I = 0.826\;{\rm{A}}
$
Therefore the current that flows through a $115\;\Omega $ resistor when there is a $95.0\;{\rm{V}}$ potential difference across the resistor is $0.826\;{\rm{A}}$.

Note: Ohm’s law is valid only when the temperature is remaining constant. In certain components, the current may result in heat energy and thus by increases in temperature. In these cases, Ohm’s law cannot be applied.