| Directions : (36-40) |
| Step-Down Transformer in the Transmission of Electric Power |
| Step-down transformers are used to decrease or step-down voltages. These are used when voltages need to be lowered for use in homes and factories. |
| A small town with a demand of 800 kW of electric power at 220 V is situated 15 km away from an electric plant generating power at 440 V. The resistance of the two wire line carrying power is \[5\centerdot 5\,\Omega \] per km. The town gets power from the line through a 4000 - 200 V step-down transformer at a sub-station in the town. |
 |
A) \[25\,\Omega \]
B) \[30\Omega \]
C) \[35\Omega \]
D) \[15\Omega \]
Correct Answer: D
Solution :
Resistance of the two wire lines carrying power \[=0.5\,\Omega /km\] Total resistance \[=\left( 15+15 \right)0\,.\,5=15\Omega \]
You need to login to perform this action.
You will be redirected in
3 sec
