Question

In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.

Answer 1

Water (other than distilled water) is a good of conductor of electricity. If the electrical supply for the area is not shut off and water is poured over electrical appliances, the electricity may pass through water and harm the firemen or can catch fire which is in contact with water. That is why, in case of a fire, the firemen shut off the main electrical supply for the area before they use the water hoses.