Ohm's Law is a fundamental principle in the field of electronics and electrical engineering. It states that the voltage (V) across a conductor is directly proportional to the current (I) flowing through it, with the proportionality constant being the resistance (R) of the conductor. The formula for Ohm's Law is:
\[ V = I \cdot R \]
Where:
- \( V \) is the voltage (measured in volts, V)
- \( I \) is the current (measured in amperes, A)
- \( R \) is the resistance (measured in ohms, \(\Omega\))
To find the electric current, we can rearrange the formula:
\[ I = \dfrac{V}{R} \]
Example 1: Current in a Household Circuit
Question: A household circuit operates at a voltage of 120 volts and the resistance of the appliance is 60 ohms. How much current flows through the appliance?
Calculation:
Given:
- \( V = 120 \) V
- \( R = 60 \) \(\Omega\)
Using the formula:
\[ I = \dfrac{120}{60} = 2 \text{ A} \]
Result: The current flowing through the appliance is 2 amperes.
Example 2: Current in a Car Headlight
Question: A car headlight operates at a voltage of 12 volts and has a resistance of 6 ohms. How much current flows through the headlight?
Calculation:
Given:
- \( V = 12 \) V
- \( R = 6 \) \(\Omega\)
Using the formula:
\[ I = \dfrac{12}{6} = 2 \text{ A} \]
Result: The current flowing through the car headlight is 2 amperes.
Example 3: Current in a Smartphone Charger
Question: A smartphone charger operates at a voltage of 5 volts and has a resistance of 2.5 ohms. How much current flows through the charger?
Calculation:
Given:
- \( V = 5 \) V
- \( R = 2.5 \) \(\Omega\)
Using the formula:
\[ I = \dfrac{5}{2.5} = 2 \text{ A} \]
Result: The current flowing through the smartphone charger is 2 amperes.
By understanding and applying Ohm's Law, we can easily calculate the electric current flowing through various devices and circuits. This is essential for designing and troubleshooting electrical and electronic systems.
