Why is a tokamak shaped like a doughnut?
Containing a hot plasma is not like putting water in a bowl. A tokamak uses a doughnut-shaped chamber and magnetic fields to guide charged particles, with different parts of the magnetic system helping confine, shape, and control the plasma.
Questions you could explore
- What does closing the path into a ring solve, and what does it leave unsolved?
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- ITER OrganizationWhat is a tokamak?
Introduces the doughnut-shaped chamber and explains why magnetic control is central to this reactor design.
- ITER OrganizationMagnets
Describes the different jobs of ITER’s magnetic systems, beyond a single simple ring field.
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