Paper 1 October/November 2010 Physical Science (0652) IGCSE

An evacuated glass bulb contains a small tungsten filament T and a metal plate P.
Filament T is heated and particles are emitted from it by thermionic emission.
The particles emitted from filament T are attracted towards plate P.
What is the sign of the charge on the particles and what is the sign of the charge on plate P?