Basic Electricity 2, WASSCE (PC), 2017

Question 2

;

  1. State the effect of temperature rise on resistance of a conductor.
  2. (i)  State ohms law

(ii) A 4.0 m long 16mm2 aluminium wire has a potential difference of 1.5V across it. If the resistivity of aluminium is 2.70 x 10-8 Ωm, calculate the current I flowing through the wire.

 

Observation

 The expected answers were;

  1.   Temperature rise in conductors leads to rise in resistance                                
  1. (i)   Ohm’s law states that the current flowing through a metallic conductor (e.g. wire) is directly proprtional to the potential difference across its ends provided that temperature and other physical condidtions of the conductor are kept constant.