🔍 Key Concepts

• Eddy currents and how they form in solid metal cores when exposed to changing magnetic fields • Purpose of laminations in magnetic circuits of electrical machines • Difference between hysteresis losses and eddy current losses in D.C. motor armatures

💭 Think About

• When a magnetic field in the armature changes, what happens inside a solid steel core compared to a laminated one? • Which type of loss is directly related to circulating currents induced in the metal itself, and how do thin insulated sheets affect those currents? • Which of the options refers to a phenomenon that is reduced by changing the physical construction of the core versus changing magnetic properties of the material?

✅ Before You Answer

• Identify which choice is specifically connected to circulating currents induced in the core material • Confirm which loss is reduced by breaking up the metal path with insulation between thin sheets • Distinguish between losses affected by material selection (like hysteresis) and those affected by physical construction (like laminations)