The current in the primary winding of the transformer is 2A, the voltage across it is 120V.

The current in the primary winding of the transformer is 2A, the voltage across it is 120V. What is the current in the secondary winding if the voltage across it is 30V? What type is this transformer?

I1 = 2 A.
U1 = 120 V.
U2 = 30 V.
I2 -?
For the transformer, the following ratio is valid: I1 / I2 = U2 / U1, where I1 and U1 are the current and voltage in the primary winding, I2 and U2 are the current and voltage in the secondary winding.
I2 = I1 * U1 / U2.
I2 = 2 A * 120 V / 30 V = 8 A.
The transformation ratio k is determined by the formula: k = U1 / U2.
k = 120V / 30V = 4> 1 step-down.
Answer: the current in the secondary winding is I2 = 8 A, a step-down transformer.