Physics 2021 JAMB Past Questions - Question 9: Which of these losses occurs in a transformer? (i) hysteresis loss (ii) Eddy current loss (iii) stray load loss (iv) mechanical loss

Correct Answer

A

Explanation

The terms you've mentioned—hysteresis loss, eddy current loss, stray load loss, and mechanical loss—are typically associated with electrical machines, such as transformers and electric motors. However, in the context of a transformer, the relevant losses are hysteresis loss and eddy current loss.

(i) Hysteresis Loss: This occurs due to the magnetic properties of the core material. The magnetic field in the core causes the core material to undergo magnetization and demagnetization cycles as the alternating current passes through it. This results in energy losses in the form of heat.

(ii) Eddy Current Loss: Eddy currents are circulating currents induced in the core material due to the changing magnetic field. These circulating currents create resistance in the material, leading to energy losses in the form of heat.

On the other hand, stray load loss and mechanical loss are more commonly associated with electric motors rather than transformers.

(iii) Stray Load Loss: This term is often used in the context of electric motors and refers to losses that occur when the motor is operating under partial load conditions.

(iv) Mechanical Loss: This refers to losses associated with the mechanical components of an electric machine, such as friction and windage losses. It is more relevant to motors where mechanical components are involved.

In summary, hysteresis loss and eddy current loss are the primary losses in a transformer, while stray load loss and mechanical loss are more commonly associated with electric motors.