Electromagnets and tuning forks

[kjsimo8]

I'm trying to get a steel tuning fork to remain vibrating at its designed frequency using an electromagnet. Is there any correlation between the strength of the electromagnet and frequency of the tuning fork, or is it more dependent upon the type of steel, size of the fork, distance, etc, etc..?

 

[Bobbywhy]

Assuming your electromagnet is strong enough to pull/push on the forks, the critical variable is the frequency of the drive signal. It needs to be exactly the same as the resonant frequency of the tuning fork. If you are using a signal generator as a source try to "tune" the frequency slightly in each direction around the center frequency. Then you could listen to the tuning fork for mazimum sound output.

 

[Averagesupernova]

Watch the current drawn by the electromagnet as you sweep through the range of frequencies. Max efficiency will occur at the resonant frequency of the fork.