I am trying to find out how to work out the power dissipated across transistors.

In particular:

- A Darlington transistor with a saturation voltage of 1.8V at 5A collector current
- an n-channel MOSFET with RDS (on) = 0.4 Ohms

I need to work out the power dissipated by each device when it is switched on.

Any help would be greatly appreciated!