If a transformer has a primary voltage of 120 volts and 200 turns of wire, with 4,000 turns on the secondary side, what is the secondary voltage?

To determine the secondary voltage of a transformer, the turns ratio between the primary and secondary coils can be used, which is fundamental in transformer calculations. The formula that relates the voltages and the number of turns in a transformer is as follows:

[ \frac{V_p}{V_s} = \frac{N_p}{N_s}

]

where:

• (V_p) is the primary voltage,
• (V_s) is the secondary voltage,
• (N_p) is the number of turns on the primary side,
• (N_s) is the number of turns on the secondary side.

In this case, you have:

• (V_p = 120) volts,
• (N_p = 200) turns,
• (N_s = 4000) turns.

Using the formula, you rearrange it to find (V_s):

[ V_s = V_p \times \frac{N_s}{N_p} ]

Substituting in the known values:

[ V_s = 120 \times \frac{4000}{200} ]

Calculating the ratio:

[ \frac{4000}{200} = 20 \