Question

In a transformer, number of turns in the primary coil are 140 and that in the secondary coil are 280. If current in primary coil is 4 A, then that in the secondary coil is ______.

Options

• 4 A

• 2 A

• 6 A 

• 10 A

Answer 1

In a transformer, number of turns in the primary coil are 140 and that in the secondary coil are 280. If current in primary coil is 4 A, then that in the secondary coil is 2 A.

Explanation:

Number of turns in primary N_p = 140

Number of turns in secondary N_s = 280, I_P = 4A, I_s = ?

Using transformation ratio for a transformer `"I"_"s"/"I"_"p"="N"_"p"/"N"_"s"`

⇒ `I_s/4 = 140/280`

⇒ I_s = 2 A