DC Motor Efficiency: Why Does Efficiency Plot Look Like Parabola?

[George444fg]

So I am doing an experiement about DC motors, and I would like to know why the efficiency plot looks like a parabola. What is the structure behind that. Thank you in advance

 

[berkeman]

So I am doing an experiement about DC motors, and I would like to know why the efficiency plot looks like a parabola. What is the structure behind that. Thank you in advance

What have you found so far in your searching? I did a Google search on what affects dc motor efficiency and got lots of good hits. Have you tried that search yet?

 

[George444fg]

What have you found so far in your searching? I did a Google search on what affects dc motor efficiency and got lots of good hits. Have you tried that search yet?

To be honest I did it simultaneously, and obviously at the end I found out what I was seeking . Thank you

 

[berkeman]

Great! Yeah, there's lots of good info out there. I didn't realize that air resistance losses were significant at higher motor speeds...