Question

State Ohm’s Law and describe its V-I graph.

Hint:

Ohm’s Law states \(V = IR\). The V–I graph is a straight line passing through the origin, showing that voltage is directly proportional to current and the slope of the graph represents resistance.

Answer 1

Concept: Ohm’s Law explains the relationship between electric current, voltage, and resistance in an electrical circuit. It states that the current flowing through a conductor is directly proportional to the potential difference across it, provided the temperature and other physical conditions remain constant.
Step 1:Statement of Ohm’s Law.
Ohm’s Law states that: " The current flowing through a conductor is directly proportional to the potential difference across its ends, provided the temperature remains constant. " Mathematically, \[ V \propto I \] or \[ V = IR \] where,

• \(V\) = Potential difference across the conductor (in volts)
• \(I\) = Electric current flowing through the conductor (in amperes)
• \(R\) = Resistance of the conductor (in ohms)

Thus, the ratio of potential difference to current remains constant and is equal to the resistance of the conductor.
Step 2:V-I Graph of Ohm’s Law.
The relationship between voltage (V) and current (I) can be represented graphically using a V-I graph.

• In the graph, potential difference (V) is taken along the vertical axis and current (I) along the horizontal axis.
• The graph obtained is a straight line passing through the origin.

This straight-line graph indicates that the potential difference is directly proportional to the current. The slope of the V-I graph represents the resistance of the conductor. \[ R = \frac{V}{I} \] Thus, a steeper slope indicates greater resistance.