Radioactivity detectors, lightning survival and magnetic field strength

[f3nr15]

1)

Methods/equipment for radioactivity detection.
For my high-school Chemistry studies, needs clarification.

Geiger counter:

A small chamber contains a high voltage electric field inside filled with inert gas. When ionizing particles/radiation enters the chamber, it will ionise the inert gas atoms, giving them a charge which will attract them to the cathode, conducting electricity which is registered on a meter.

Cloud chamber:

A chamber that contains super-saturated liquid vapours (water or alcohol?) and as radioactive particles/radiation enters the chamber they will ionize particles inside which can be traced.

That's all I know, there's the Scintillation counter and radioactive film badges I'm not clear about and I heard there's something called the bubble chamber which apparently superseded the cloud chamber.

2)

If lightning can create 100A in 0.1s, when a person is struck by this why have there been cases where this unfortunate victim has survived ?

3)

Question: Define magnetic field strength (T)
Answer: Magnetic flux density (Wb.m^-2)

True ?

 

[member 553083]

Magnetic field strength is the measure of the force per unit current at a point in a magnetic field, measured in teslas (T). It is also referred to as magnetic flux density and is defined as the force per unit current per unit area. The SI unit for magnetic field strength is the Tesla (T).