How should this Beam Loading experiment be designed?

[Physical_Fire]

Homework Statement

Attached.

Relevant Equations

No need.

The question and my attempt at a solution are attached. Thanks.

 

[haruspex]

The beams are of various lengths. You did not specify where the supports or loads are to be placed, and there is no mention of distances in your table.

 

[Physical_Fire]

I kept the beam length constant. Independent variable is the force and the dependent variable is whether the beam breaks or not. The rest are constant.

 

[haruspex]

I kept the beam length constant. Independent variable is the force and the dependent variable is whether the beam breaks or not. The rest are constant.

You cannot keep the beam length constant. You can keep the distance between the supports constant, but how to determine that distance, and where exactly should each beam be placed across them? And where should the load be placed?
A key aspect of experimental design specification is that others can repeat exactly what you did.

A trickier problem is what load to start with and by how much to increase it at each step. You cannot go back and try a slightly smaller load when it breaks. If you increase by large steps you will end up with a big margin of error; if you go in tiny steps it'll take a month.
Maybe that's beyond what is expected here, but can you think of an approach?

 

[Physical_Fire]

You cannot keep the beam length constant. You

Why not?

A key aspect of experimental design specification is that others can repeat exactly what you did.

Why can't they repeat?

 

[Physical_Fire]

but how to determine that distance

That distance is an arbitrary distance within the scope of the beam, where different masses would be placed on it until the beam breaks

 

[haruspex]

Why not?

Because the beams provided are of various lengths.

Why can't they repeat?

Because as your description stands there is not enough information. You leave many details unspecified.

That distance is an arbitrary distance within the scope of the beam, where different masses would be placed on it until the beam breaks

Not good enough. You need to say how you will choose the distance. If the beam lengths available are 2m, 3m and 12m, what distance would you choose?

Now, I did not set this question. Maybe you are not expected to address these points. I can only discuss how I would answer it.

 

[Physical_Fire]

I am genuinely confused. Why can't the loads be the independent variable as the loads are being changed?

 

[haruspex]

I am genuinely confused. Why can't the loads be the independent variable as the loads are being changed?

I did not say that. Which of my comments is that a response to?

 

[Physical_Fire]

You cannot keep the beam length constant.

This. All in all, I don't get the idea as to what the variables are.

 

[Physical_Fire]

Gotcha