B5 practical: Resistivity of Play Doh
Play Doh is modelling clay made out of flour oil and salt, the salt content enables it to conduct electricity so it has a measurable resistance. In this experiment the resistance of a cylinder of play Doh will be measured as it is squashed between 2 metal plates. The resitivity of a conductor is given by R=ρL/A Where: ρ = resistivityL = lengthA = Cross sectional area The sample to be squashed has a constant volume...