If Np:Ns = 2:1, what is the current ratio Ip:Is?

If Np:Ns = 2:1, what is the current ratio Ip:Is?

• A. 1:2
• B. 2:1
• C. 1:1
• D. 3:1

Answer: (A)

In an ideal transformer, current ratio is the inverse of the turns ratio because power must be conserved (Vp Ip ≈ Vs Is). Given Np:Ns = 2:1, the turns ratio Np/Ns = 2. The corresponding current ratio is Ip/Is = Ns/Np = 1/2. So the primary current is half the secondary current, making Ip:Is = 1:2. This aligns with the idea that the transformer steps down voltage (higher turns on the primary) and the current increases on the secondary to maintain power, resulting in a 1:2 relationship between primary and secondary currents.

In an ideal transformer, current ratio is the inverse of the turns ratio because power must be conserved (Vp Ip ≈ Vs Is).

Given Np:Ns = 2:1, the turns ratio Np/Ns = 2. The corresponding current ratio is Ip/Is = Ns/Np = 1/2. So the primary current is half the secondary current, making Ip:Is = 1:2. This aligns with the idea that the transformer steps down voltage (higher turns on the primary) and the current increases on the secondary to maintain power, resulting in a 1:2 relationship between primary and secondary currents.