Rankers Physics

Alternating Current: Practice Problem & Solution

48. The core of a transformer is laminated because: (2006)
Energy losses due to Eddy currents may be minimised
The weight of the transformer may be reduced
Rusting of the core may be prevented
Ratio of voltage in primary and secondary may be increased

Solution Explained:

To solve this problem, we apply the core principles of Alternating Current. Understanding the underlying formula is key to arriving at the correct answer below:

A solid metal core allows large eddy currents, which lead to significant energy loss as heat.
By laminating the core, its electrical resistance is increased.
This restricts the paths of the eddy currents and minimizes the associated energy losses.

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