How should I express this angle in words?

[ChanYoung Park]

Hi! The diagram above is showing a man swinging a swing (a facility you can find in playgrounds) back and forth. I'm trying to come up with a concise expression in words that describes the angle noted as theta so that I can write a clear and effective research question (theta is the independent variable in my research). How should I express this angle in words (or in English)??

 

[NickTheFill]

My attempt...
Where theta is the displacement angle of the swing from equilibrium.

 

[FactChecker]

My attempt...
Where theta is the displacement angle of the swing from equilibrium.

With positive angles in the forward direction.

 

[Nidum]

--- relative to the vertical . You must always provide a datum zero for any position variable in mechanics .

 

[ChanYoung Park]

--- relative to the vertical . You must always provide a datum zero for any position variable in mechanics .

With positive angles in the forward direction.

My attempt...
Where theta is the displacement angle of the swing from equilibrium.

So will it be
"Displacement angle of swing from equilibrium relative to the vertical with positive angles in the forward direction"...?

 

[sophiecentaur]

How should I express this angle in words (or in English)??

I would have thought that a diagram with the displacement angle and the restoring force marked would be quite good enough. It is a very standard set up and not likely to be to be misunderstood. Maths is often better than words to describe such things. No need to worry overmuch. I think.

 

[FactChecker]

I would have thought that a diagram with the displacement angle and the restoring force marked would be quite good enough. It is a very standard set up and not likely to be to be misunderstood. Maths is often better than words to describe such things. No need to worry overmuch. I think.

Even with full use of mathematics, a careful and precise definition of the variables and coordinate systems is a good practice.

 

[ChanYoung Park]

I would have thought that a diagram with the displacement angle and the restoring force marked would be quite good enough. It is a very standard set up and not likely to be to be misunderstood. Maths is often better than words to describe such things. No need to worry overmuch. I think.

The problem is that I will get marks for my research question and it will be marked based on how clear the dependent and indenpendent variables are; it's mentioned in the criteria...

 

[FactChecker]

The problem is that I will get marks for my research question and it will be marked based on how clear the dependent and indenpendent variables are; it's mentioned in the criteria...

Then you want a diagram and the correct word descriptions. The diagram helps very much to visualize but I have seen many diagrams that get too complicated to really be clear about each part. Therefore, clear word definitions are also nice.

 

[Delta2]

Can't we simply call it "inclination angle" or "polar angle"?. Isn't it so if we choose a spherical coordinate system with its origin at the hinge? (and proper directions for positive orientation).