Finding wave frequency by using a strobe

[primarygun]

I've learned about finding wave frequency by using a strobe.
The book suggest that we first find out the frequency by the "frozen" properties.
I think this method is rather inaccurate.
If I am carrying out the experiment, I would first find the wavelength and the velocity. Do you ?

 

[HallsofIvy]

HOW would you go about finding the wavelength and velocity?

Yes, depending on the situation, using the rather primitive apparatus I suspect you are using (when I first did this we used a disk with a hole turned by hand!) but I don't see any simple way of finding the wavelength and velocity- what equipment do you have?

 

[primarygun]

A ruler to measure the distance between two crests when it is frozen,
Measure distance traveled in a given time to find out the velocity.

 

[HallsofIvy]

To see if that is more reasonable, we would have to know exactly what equipment you are working with and what kind of wave you have. A strobe light in a darkened room illuminating a wave in a string?