When does a body have a power of 1 watt

An object is said to be rated 1 Watt when it performs a work worth 1 Joule  in 1 second.

Explanation:

We know that power is rate of doing work or Work done in a given period of time.

Power is simply given by the formula:

Power=(Work)/(Time)

The SI unit of Power, Work and Time are Watts, Joules and Seconds respectively.

Hence, 1 Watt=1 Joule/ 1 Second

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.