The formula to calculate the inductance (L) of a toroid is:
\[ L = \frac{u \cdot N^2 \cdot A}{2 \pi r} \]
Where:
Let's say the permeability of the core is 100, the number of turns is 50, the cross-sectional area is 2 cm², and the radius to the center line is 5 cm. Using the formula:
\[ L = \frac{100 \cdot 50^2 \cdot 2}{2 \pi \cdot 5} \]
We get:
\[ L = \frac{100 \cdot 2500 \cdot 2}{10 \pi} \approx \frac{500000}{31.42} \approx 15915.49 \]
So, the inductance (\( L \)) is approximately 15915.49 henries.
In general terms, a toroid is a surface of revolution with a hole through the center. In electronics, the term toroid is used to describe transformers and inductors that use magnetic cores in the toroid shape. These components are known as passive electronic components. Toroid transformers and inductors are superior to square devices and have better electrical performance.