Question

The purpose of colour coding resistors is to-
1. identify the type of circuit they may be used in
2. identify whether they are ohmic or non-ohmic
3. determine the resistance value 
4. determine if they are suited for series or parallel connection

Answer 1

Correct Answer - Option 3 : determine the resistance value 

The correct answer is option 3) i.e. determine the resistance value 

CONCEPT:

• Resistance: The hindrance to the flow of current offered by a material is called electrical resistance.
  • The SI unit of electrical resistance is the ohm (Ω)

 The resistance of a conducting wire is given by the equation:

\(R = ρ\frac{l}{A}\)

Where R is the resistance, l is the length of the wire and A is the cross-sectional area of the material.

EXPLANATION:

• In cases where the dimensions and resistivity of the resistor are not known, it is difficult to calculate the resistance value.
• This complication is avoided by the colour coding of resistors.
• The resistor colour code is designed to find the resistance and tolerance values of each resistor.
• A number of coloured bands are marked on the resistor and each band corresponds to a numerical value or multiplier or tolerance value.
• Therefore, the purpose of colour coding resistors is to determine the resistance value.