For the 120-V/24-V transformer rated at 20 VA, the secondary current is approximately 0.83 A.

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Multiple Choice

For the 120-V/24-V transformer rated at 20 VA, the secondary current is approximately 0.83 A.

The rating in VA tells you the maximum apparent power the transformer can deliver. For the secondary, the maximum current is found from S = V_secondary × I_secondary. With 20 VA and 24 V on the secondary, I_secondary = 20 / 24 ≈ 0.833 A, which rounds to about 0.83 A. That’s why the secondary current is approximately 0.83 A. The other values come from using the primary voltage or from exceeding the rating: 0.17 A would be the primary current (20 VA / 120 V), not the secondary; 1.0 A would require 24 VA on the secondary, which exceeds the 20 VA rating; 2.0 A would imply 48 VA, also exceeding the rating.

The rating in VA tells you the maximum apparent power the transformer can deliver. For the secondary, the maximum current is found from S = V_secondary × I_secondary. With 20 VA and 24 V on the secondary, I_secondary = 20 / 24 ≈ 0.833 A, which rounds to about 0.83 A. That’s why the secondary current is approximately 0.83 A.

The other values come from using the primary voltage or from exceeding the rating: 0.17 A would be the primary current (20 VA / 120 V), not the secondary; 1.0 A would require 24 VA on the secondary, which exceeds the 20 VA rating; 2.0 A would imply 48 VA, also exceeding the rating.

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