Question

Why is speed relative?

Answer 1

Hi!

Speed is relative because when we measure speed we do so based on our position on the earth and not our position relative to space.

Answer 2

You can read a book or take a nap sitting comfy in your soft chair in a passenger airliner flying 500 miles per hour.

What's your REAL speed ? Is it zero or is it 500 miles per hour ? It's both. It just depends on what the reference is.