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.
Solution and Explanation
The water usually contain salts and is a good conductor of electricity.
To save themselves and others from electric shock and to avoid any short circuit, firemen shut off the main electrical supply for the area.
Top Questions on Chemical Effects of Electric Current
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Concepts Used:
Electric Current
Defining Electric Current
It is the rate of flow of electrons in a conductor. SI Unit - Ampere (A).
Electrons are negatively charged particles hence when they move a number of charges moves.
Note:- The ability of a particular substance to conduct electricity depends on the number of electrons that are able to move . Some of the materials allow current to flow better than others.
What is an Electromotive Force?
If a force acts on electrons to make them move in a particular direction, then up to some extent random motion of the electrons will be eliminated. An overall movement in one direction. The force which acts on the electrons to move them in a certain direction is known as electromotive force and its quantity is known as voltage and is measured in V.