An ideal step-down transformer has a primary coil of 300 turns and a secondary coil of 18 turns. it is plugged into an outlet with 230.0 v (ac) and it draws a current of 0.31 a. calculate the voltage in the secondary coil. (in v) 1.38×101 v you are correct. your receipt no. is 154-2147 : receipt previous tries calculate the current in the secondary coil. (in a) 5.17 a you are correct. your receipt no. is 154-6875 : receipt previous tries calculate the average power dissipated.

1) 13.8 V

We can use the transformer equation:

where we have

is the number of turns in the primary coil

is the number of turns in the secondary coil

is the voltage in the primary coil

is the voltage in the secondary coil

Solving for Vs, we find

2) 5.17 A

For an ideal transformer, the power in input is equal to the power in output, so we can write:

where

is the voltage in the primary coil

is the voltage in the secondary coil

is the current in the primary coil

is the current in the secondary coil

Solving for Is, we find

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .