Question

in case of fire before the Fireman use water hose they shutt off the main electrical supply for area explain why they do this

Answer 1

due to the fire electric current carrying wires may burn and their insulation thus removes. as water contains some impurities thus it is good conductor of electricity and if water falls on these wires they will give electric shock

Answer 2

Hello Friend,

I hope You understand this

Answer:

In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area because water sprayed from the hose might conduct electricity which may come in contact with the electrical appliances which increases the chance of electricity passing through wire. This may hurt the fireman.