Which of the following are variable losses

Electrical Engineering XYZ MCQs

Which of the following are variable losses:

1. Armature copper loss
2. Eddy current loss
3. Hysteresis loss
4. Shunt field copper loss

Correct answer: 1. Armature copper loss

Explanation: Armature copper loss is a variable loss because it is dependent on the armature current, which can vary with the load on the motor or generator. The armature copper loss can be calculated using the formula 𝑃_cu=𝐼_𝑎²𝑅_𝑎​, where I_a​ is the armature current and R_a​ is the resistance of the armature windings. As the load varies, the armature current varies, hence the armature copper loss varies accordingly.