Question

often, a crackling sound is heard while listening to radio during lightning .can you explain why ??

Answer 1

When a lightening occurs in the sky its impact is felt on all the different electromagnetic waves in a spectrum. Because of this impact there is a change in electrical current. This change interferes with the different radio signals being transmitted. It not only affects the radio but it has negative impact on Mobile phones and Television network. This is the reason we are advised to switch off the television when it is raining and lightning. Because lightning causes disturbances in the radio signals being transmitted a crackling sound is heard on radio during lightning. 

Answer 2

Because of the electromagnetic spectrum the radio waves gets affected but this only happens in AM radio.

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