Question

why the sky is blue​

Answer 1

Gases and particles in Earth's atmosphere scatter sunlight in all directions. 

Blue light is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.

Answer 2

Answer:

$\red \to$Bcoz in VIBGYOR (spectrum) , the blue color radiates nd scatters the most.

In the sky also this process occurs nd blue colour spreads most , that's why it looks blue...