And how much of the material does it need to be to resist underwater pressure?
not that i've heard of, usually people dropping stuff on them.
they are the worst cook tops to havei hate themthey are hard to clean, takes forever to heat anything up.
You can get thermal shock if a cold liquid cools them too quickly.like a spill.
I've had one for over ten yearsThey are some form of composite plastic, not ceramicKind of super hard plastic type material called CeranThey don't crack from normal cooking useIf you dropped something heavy enough on one, it could crackI've never had any problem with mine but they require flat bottomed pots and pans and do heat up slowly and cool down slowlyTho I like mine and have gotten used to the process.
Deep-submergence ROV's use pressure-compensation techniques as much as possible to keep weight and bulk down and reliability upThat means filling the outer shell with an inert liquid and carefully choosing the electronics parts so that a pressure casing isn't neededWhere you absolutely need a surface-pressure environment for the working parts casing depends on bulk to be accommodatedAluminum tubing with wall thickness equal to the radius of the cavity works to about 4 km and 20 cm cavity diameter, glass spheres with a 5 cm wall can enclose about a 1/2 meter diameter volume to the same depthLarger vessels tend to use steel or titanium spheresThere's a lot of careful mechanical design that goes into picking material and dimensions for those pressure casings.
