Iron
The core of the Ivy King device used Highly Enriched Uranium-235 as the fissile material.
soft iron
Electromagnet is a device consisting of a core of magnetic material such as iron, surrounded by a coil through which an electric current is passed to magnetize the core.
The difference is between how the windings relate to magnetic material around which they are wound. If this magnetic material surrounds the windings then the device is said to be a shell type transformer. If the windings cover the exterior of the magnetic material then the transformer is said to be of the core type. Please see the link.
If one could construct a boring device with a camera that could survive the heat and pressure of the journey to the inner core, the only color one would see would be a blinding whitish light from the superheated material.
The core is made up of Iron and Nickel.
A ferrite core inductor with two 47 mH windings. An inductor usually consists of a coil of conducting material.
usually a Pentium core.
The inner core of the Earth is primarily composed of solid material.
Core
No. Material cannot travel from the core to the crust.
Coaxial cables usually include a solid plastic core. The core is made of solid insulation material that helps to maintain the shape and structure of the cable, while also providing insulation for the inner conductor. This type of cable is commonly used for television and internet connections.