Question

The ratio of the number of turns of the primary to the secondary coils in an ideal transformer is 20 : 1. If 240 V ac is applied from a source to the primary coil of transformer and a 6.0 Ω resistor is connected across the output terminals, then current drawn by the transformer from the source will be ______.

पर्याय

• 4.0 A

• 3.8 A

• 0.97 A

• 0.10 A

Answer 1

The ratio of the number of turns of the primary to the secondary coils in an ideal transformer is 20 : 1. If 240 V ac is applied from a source to the primary coil of transformer and a 6.0 Ω resistor is connected across the output terminals, then current drawn by the transformer from the source will be 0.10 A.

Explanation:

Given: Turns ratio = N_s : N_p = 20 : 1

Primary voltage (V_p) = 240 V

Load resistor (R) = 6.0 Ω

Transformation ratio:

`V_p/V_s = N_p/N_s`

V_s = `240/20`

= 12 V

I_s = `V_s/R_s`

= `12/6`

= 2 A

For ideal transformation:

V_pI_p = V_sI_s

240 × I_p = 12 × 2

I_p = `24/240`

= 0.10 A