🔍 Key Concepts

• Direct current (DC) and how it creates a magnetic field around a conductor • What happens when a wire is coiled and wrapped around a soft iron core • The basic function of devices that use current to create a temporary magnetic field

💭 Think About

• What kind of device uses electricity to produce a magnetic field only when current is flowing? • Why is a soft iron core used instead of hard steel when you want a magnet that can be turned on and off? • Which option describes a device, and which options describe materials or effects rather than the actual device?

✅ Before You Answer

• Identify which choice refers to a device that becomes magnetic only when current flows • Check which terms are normally associated with crystals under pressure rather than coils and iron cores • Eliminate any answers that describe magnetic materials or properties instead of the actual coil-and-core device