Question

A DC ammeter and a hot wire ammeter are connected to a circuit in series. When a direct current is passed through the circuit, the DC ammeter shows 6A. When AC current flows through the circuit, what is the average reading in DC ammeter and the AC ammeter, if DC and AC currents flow simultaneously through the circuit?

• A. DC = 6A, AC = 10A
• B. DC = 3A, AC = 5A
• C. DC = 5A, AC = 8A
• D. DC = 2A, AC = 3A

Hint:

When both DC and AC currents are present, the DC ammeter measures only the DC component, and the AC ammeter measures the AC component.

Answer 1

The Correct Option is A

When both DC and AC currents flow simultaneously, the current measured by the DC ammeter is the sum of the DC current and the DC component of the AC current, while the AC ammeter measures the AC component. - For the DC ammeter, it measures the 6A DC current, as the DC ammeter responds to only the DC component.
- For the AC ammeter, the total current is 10A, which is the sum of the 6A DC and 4A AC components. Hence, the AC ammeter reads 10A. Thus, the correct answer is (A).