Using a tuning fork vs computer tuner for violin

[sussertown]

TL;DR Summary

Tuning fork vs computer tuner

I use a fork to tune my violin. The school teacher uses an ekectronic tuner which is low. I tried an app tuner on my phone. It is also low. How do I confirm for the teacher that these electronic tuners are not correct?

 

[Baluncore]

Welcome to PF.

I use a fork to tune my violin.

How do I confirm for the teacher that these electronic tuners are not correct?

How do you know that your fork is correct ?

 

[Vanadium 50]

As they say, "If everybody else is out of tune, it might not be everybody else."

 

[Baluncore]

How old is your tuning fork, and how is it labelled?
It should probably be marked A4, 440.00 Hz, which is the American Standard pitch, adopted in 1936. Before that, the reference was international pitch, where A4 = 435.00 Hz.

Electronic tuners are usually ten times more precise than a metal tuning fork.