Answer:
"where crests and troughs have their maxima at the same time"
Crests and troughs are 180 deg out of phase and when they have their maxima at the same time and place, their net contribution will be zero"
Answer:
Let's start by understanding what exactly a scientific question is. A scientific question is a question that may lead to a hypothesis and help us in answering (or figuring out) the reason for some observation. A good scientific question has certain characteristics. It should have some answers (real answers), should be testable.
Here's examples of a few:
Why is that a star?
or
What is that star made of?
Hope this can lead you to the answer you're looking for at least!!
Movement can be without change in positions. As only a part of it can be made to move. If you move there is a motion and if there is a motion there is a movement so they're same thing. In motion whole of body moves, but in movements only the parts of body moves.
