POWER SYSTEM MCQS-1

 MCQ-1 -To reduce the radio interference which line is/are transposed?

 Power line

 Both power and telecommunication lines

 either 1 or 2

 none of the above

ANS: either 1 or 2

HINT: If power line and telecommunication lines are running close to each other, the current flowing in the power line produces magnetic flux linkage with the communication line conductor induces an emf in the telecommunication line conductor. This is called electro magnetic induction.

Similarly due to earth effect electric field is produced by the charges of the earth induces a voltage in between the conductors of the telecommunication lines. This is called electro static induction. This both electro magnetic induction and electro static induction produces the voltage between the telecommunication line conductors which causes interference to the telecommunication signals which is called radio interference. To reduce this radio interference in the telecommunication line, either power line or both power and telecommunication lines are transposed at regular intervals of length the transmission line.