Question

Read the following paragraph and answer the question:

Long distance power transmissions

The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.

A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The number of turns in the secondary in order to get output power at 230 V are ______.

विकल्प

• 4

• 40

• 400

• 4000

Answer 1

A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The number of turns in the secondary in order to get output power at 230 V are 400.

Explanation:

Given E_i = 2300 V

E_o = 230 V

N_p = 4000

N_s = ?

`"E"_"i"/"E"_"o" = "N"_"p"/"N"_"s"`

`2300/230 = 4000/x`

x = 400 = N_s = No of turns in secondary coil