## Importance of algebra in engineering.

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jruiz
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### Importance of algebra in engineering.

Greetings.
Before making the following query, I would like to apologize if you consider that this type of question should not be asked in this forum. So if you decide that it should be removed, I would understand it perfectly.

Concerning some physics notes that I am writing, I would like to know the opinions of the engineers in this forum, which I imagine are the vast majority of users, but are also spread around the world. By the way, I'm not particularly an engineer.

Well, anyway, here is the query:
1.- When doing engineering work, on a scale of 1 to 100,
How much importance would you give to algebraic analysis and how much to numerical calculations? How much importance would you assign to the simulators in your engineering area?

2.- When calculating to obtain a specific result, where many parameters are fixed, do you directly use their numerical values? Or, do you assign names to those parameters to do algebraic calculations to get a final expression, and then substitute the numerical values?

3.- If necessary, how do you obtain critical values ​​of the parameters involved in an engineering project?

Regards

ezzieyguywuf
Posts: 656
Joined: Tue May 19, 2015 1:11 am

### Re: Importance of algebra in engineering.

1) 95 out of 100: an engineer must be very proficient at algebra. I don’t understand the question about simulators.

2) when I’m doing a calculation I usually start with a well known equation, rearrange so that my one unknown value is on one side of the equation, then substitute numbers in for my known values.

3) I usually use Wikipedia or engineering toolbox.

DeepSOIC
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Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

### Re: Importance of algebra in engineering.

ezzieyguywuf wrote:
Sun Aug 02, 2020 11:43 pm
2) when I’m doing a calculation I usually start with a well known equation, rearrange so that my one unknown value is on one side of the equation, then substitute numbers in for my known values.
I usually compute as many intermediate values i can, and do sanity check on each one, if possible. This improves my feel of the system.
This often gives additional insight of what is affecting the result in a big way and what isn't. A full expression is often useful in its own right (again, to gain insight on what matters and what doesn't), so I do sometimes derive it.

DeepSOIC
Posts: 7831
Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

### Re: Importance of algebra in engineering.

jruiz wrote:
Sun Aug 02, 2020 11:23 pm
3.- If necessary, how do you obtain critical values ​​of the parameters involved in an engineering project?
If critical, measure, and compare to typicals/specs. In case of doubt, think hard, consider sources of error, remeasure.

DeepSOIC
Posts: 7831
Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

### Re: Importance of algebra in engineering.

jruiz wrote:
Sun Aug 02, 2020 11:23 pm
1.- When doing engineering work, on a scale of 1 to 100,
How much importance would you give to algebraic analysis and how much to numerical calculations? How much importance would you assign to the simulators in your engineering area?
As far as engineering goes, most of my engineering is electronics. There, I very rarely use simulators, mostly in situations where i doubt my expectations. If the system is complex enough that I can't estimate its behavior and it needs a simulation, I usually assume i'm over- or under-engineering it, and there should be an easier (but maybe more expensive) solution. Simulation - 5, algebraic - 95.

jruiz
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### Re: Importance of algebra in engineering.

Thank you very much for answering my questions.
ezzieyguywuf wrote:
Sun Aug 02, 2020 11:43 pm
1) 95 out of 100: an engineer must be very proficient at algebra.
Cool! Very good to know this information.
ezzieyguywuf wrote:
Sun Aug 02, 2020 11:43 pm
I don’t understand the question about simulators.
As far as I know, electrical engineers could use simulators to calculate how power is distributed in a network. Also it seems to me that they use them to calculate critical values of some parameters.
ezzieyguywuf wrote:
Sun Aug 02, 2020 11:43 pm
2) when I’m doing a calculation I usually start with a well known equation, rearrange so that my one unknown value is on one side of the equation, then substitute numbers in for my known values.

3) I usually use Wikipedia or engineering toolbox.
Would you mind telling me what engineering do you do?
Thanks a lot again

jruiz
Posts: 292
Joined: Tue Oct 28, 2014 1:07 pm
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### Re: Importance of algebra in engineering.

DeepSOIC wrote:
Mon Aug 03, 2020 12:08 am
jruiz wrote:
Sun Aug 02, 2020 11:23 pm
1.- When doing engineering work, on a scale of 1 to 100,
How much importance would you give to algebraic analysis and how much to numerical calculations? How much importance would you assign to the simulators in your engineering area?
As far as engineering goes, most of my engineering is electronics. There, I very rarely use simulators, mostly in situations where i doubt my expectations. If the system is complex enough that I can't estimate its behavior and it needs a simulation, I usually assume i'm over- or under-engineering it, and there should be an easier (but maybe more expensive) solution. Simulation - 5, algebraic - 95.
Thank you very much.
I find it impressive that engineers place so much value on algebra. I had another impression.
Thanks for clarifying that detail

jruiz
Posts: 292
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### Re: Importance of algebra in engineering.

DeepSOIC wrote:
Sun Aug 02, 2020 11:59 pm
jruiz wrote:
Sun Aug 02, 2020 11:23 pm
3.- If necessary, how do you obtain critical values ​​of the parameters involved in an engineering project?
If critical, measure, and compare to typicals/specs. In case of doubt, think hard, consider sources of error, remeasure.
Ok. thanks.

ezzieyguywuf
Posts: 656
Joined: Tue May 19, 2015 1:11 am

### Re: Importance of algebra in engineering.

jruiz wrote:
Mon Aug 03, 2020 12:19 am
Would you mind telling me what engineering do you do?
Thanks a lot again
Mechanical engineering.

Regarding simulations, we use that in the mechanical world, say for stress analysis or aerodynamics etc In other words “is the material strong enough”, “is the design sleek enough” that kind of thing.

However, in my experience these simulations are a great starting point for iterating early and often. However, it’s usually very hard to hs e a simulation fully mimic real life. Because of this, I’m very skeptical of using simulated data for much more than comparing iterative designs, and rely much more heavily on physical testing.

That being said, it is possible to achieve very accurate and realistic results from simulations, but that’s like a full time job itself, and not practical for your very day engineer.

I agree with Deepsoic regarding measuring and comparing.

Finally, dimensional analysis is critical in engineering. It’s often tedious and seems pointless (“I know I’m dealing with meters why do I have to write it each time”) but honestly so many mistakes can be caught sooner by ensuring that equations are dimensionally homogeneous. This in essence is a bit of a mini-algebra problem.

jruiz
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### Re: Importance of algebra in engineering.

@ezzieyguywuf, @DeepSOIC

Thank you for your comments. It is very enriching to know the point of view of the engineers in this regard.
How good it would be if other engineers were encouraged to give their opinions.