Why are danger signals red in colour ?...

Why are danger signals red in colour ?

Text Solution

Verified by Experts

As `lambda_( r)` is largest in the visible region, therfore, red colour is least scattered. Hence it can be seen from large distance. That is why danger signals are red.

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The danger signals are red in colour because it is :

strongly scattered by fog or smoke

least scattered by fog or smoke

least obsorbed by fog or smoke

strongly absorbed by fog or smoke

Assertion (A) : Danger signals are made of red colour. Reason(R): Velocity of red light is maximum in air, so signals are visible in dark.

Both Assertion and Reason are true and Reason is correct explanation of A.

Both Assertion and Reason are true and Reason is not correct explanation of Assertion.

Assertion is true but Reason is false.

Assertion is false but Reason is true

Methyl orange gives red colour in

sodium bicarbonate solution

sodium chloride solution

hydrochloric acid solution

potassium hydroxide solution