An ac ammeter is used to measure current in a circuit. When a given direct current passes through the circuit, the ac ammeter reads 3 A. When another alternating current passes through the circuit, the ac ammeter reads 4 A. Then find the reading of this ammeter (in A), if dc and ac flow through the circuit simultaneously.

Question

An ac ammeter is used to measure current in a circuit. When a given direct current passes through the circuit, the ac ammeter reads 3 A. When another alternating current passes through the circuit, the ac ammeter reads 4 A. Then find the reading of this ammeter (in A), if dc and ac flow through the circuit simultaneously. (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

Net current: I=3+4 √2 sin ω t Now find I v =√(∫ limits0T(3+4 √2 sin ω t)2 d t/T)=5 A

Net current: I=3+42​sinωt Now find Iv​=T0∫T​(3+42​sinωt)2dt​​=5A

Net current: $I = 3 + 42 sin ω t$
Now find $I_{v} = \frac{0 \int T ( 3 + 4 2 s i n ω t ) ^{2} d t}{T} = 5 A$