The first thing to do is watch Kahn Academies video on calculating decibels
The video also points out how sensitive the human ear is.
P = power in Watts (W) = Work / time
Work is an energy measurement. What is energy? That’s a question which will stump pretty much everyone. The answer is probably another question. Why? Don’t hurt your brain with this one too much…. moving on.
J = Joules = an energy measurement.
Work(J) = Force * Distance
Force = measured in Newtons (N)
1N = about 102grams * gravity
The actual formula being
F = m * a
Force = mass * acceleration
So 1 Newton of force is about half the mass of your house / car keys just sitting in your hand.
Lift your car keys 1 metre in one second. That is 1 Watt of energy.
You car keys have a footprint that fills the palm of your hand. You can feel it.
Spread that weight over 3 times the size of Germany, or for the Aussies reading this, a bit less than the size of the Northern Territory. You couldn’t feel that with your hand, but your ears could hear it.
OK, It have to come back to this article to explain how it relates to long range flying.