Calculate the required Cross sectional area of toroidal core

[SanPhysics]

For example how to calculate required cross-section area of the toroidal core for 100VA transformer.Is that any simple formula.

 

[Baarken]

See if this is of any help: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/indtor.html

Based on your requirements, find the required inductance. With the inductance, you can calculate a good approximation of the required cross-sectional area based on the formula in the link above.

 

[Averagesupernova]

A quick search turned up: http://www.changpuak.ch/electronics/amidon_toroid_calculator.php

No experience using it.