I am a bit confused on how l incorporate the area of the hysteresis loop into all this. Do l just plus in the 6.25 square centimetres or l have to do something with the relations of H and B which they gave me.

 

The B-H plot on graph paper is giving 6.25cm^2 for the hysteresis loop area.

Scaling of the graph paper area gives 1cm^2 <=> 50[At/m]*0.2[T]=10 Joules per m^3.

So 6.25cm^2 <=> 62.5 J/m^3

You have a core volume of 450 cm^3 <=> 450x10^-6 m^3

At 60Hz you then find the power in MKS [SI] system units.

 

Another thing which l do not understand is how to calculate the power in watts/kg. In my calculations l have J/s and l am given the density. I do not know to calculate for the

 

Your PH will come out directly as Watts - [1Watt=J/s]

So you have a certain value in Watts for a given volume. That can be equated to the same watts for a given mass since mass=volume x density.

You didn't state what the density is but if it's for transformer steel the typical density is ~7600kg/m^3.

So a volume 450cm^3 has a mass of ~3.4kg.

So if it is steel with that density your PH/3.4 gives the watts per kg ......