An electric heater is connected to the voltage supply. After few seconds Current gets its steady value then its initial current will be

Options

A. equal to its steady current
B. slightly higher than its steady current
C. slightly less than its steady current
D. zero

Explanation

To determine the initial current of an electric heater connected to a voltage supply, we can analyze the behavior of the current over time as the heater heats up. Here’s a step-by-step solution:

### Step 1: Understanding the Circuit
When an electric heater is connected to a voltage supply, it behaves like a resistive load. The current flowing through it can be described by Ohm's Law:
\[ I = \frac{V}{R} \]
where \( I \) is the current, \( V \) is the voltage, and \( R \) is the resistance of the heater.

### Step 2: Initial Current
At the moment the heater is switched on, the temperature of the heater is at room temperature, and the resistance is at its lowest value. Thus, the initial current \( I_0 \) can be expressed as:
\[ I_0 = \frac{V}{R_0} \]
where \( R_0 \) is the initial resistance of the heater.

### Step 3: Steady State Current
As the heater operates, it heats up due to the heating effect of the current. As the temperature increases, the resistance of the heater also increases. This leads to a decrease in current until it reaches a steady state value \( I \):
\[ I = \frac{V}{R} \]
where \( R \) is the resistance at the steady state (after the heater has warmed up).

### Step 4: Relationship Between Initial and Steady State Current
Since the heater's resistance increases with temperature, the initial current \( I_0 \) will be slightly higher than the steady state current \( I \):
\[ I_0 > I \]
This means that the initial current will be greater than the steady state current due to the lower initial resistance.

### Step 5: Conclusion
In conclusion, the initial current \( I_0 \) when the heater is first connected to the voltage supply is slightly higher than the steady state current \( I \) because of the lower resistance at the start.