... theory and practice
Hi,
I just built a small Helmholtz coil and see a discrepancy between theory and practice.
The calculation using two different fornulas have as result the exact same value in Tesla or µT. Below in the attached images.
Now measuring with a magnetometer of a cell phone gives me a more or less 50% real value compared to the calculated theoretical value. Measured with tw different phones. You can also see that the substraction (changin the polarity of the input voltage) of the geomagnetic field gives me plus/minus the same value.
Any explanation why so ?
Thanks in advance for comments
regards Rainer
Hi,
I just built a small Helmholtz coil and see a discrepancy between theory and practice.
The calculation using two different fornulas have as result the exact same value in Tesla or µT. Below in the attached images.
Now measuring with a magnetometer of a cell phone gives me a more or less 50% real value compared to the calculated theoretical value. Measured with tw different phones. You can also see that the substraction (changin the polarity of the input voltage) of the geomagnetic field gives me plus/minus the same value.
Any explanation why so ?
Thanks in advance for comments
regards Rainer