Here is a little problem from the physical/electro-technical area. Only basic knowledge about electricity and resistance is required, like:

• The replacement resistance of two serial-connected resistances
  
  is 2 Ohm (R_replacement = R₁ + R₂, where R₁ = R₂ = 1).
• The replacement resistance of two parallel-connected resistances
  
  is 1/2 Ohm (1/R_replacement = 1/R₁ + 1/R₂, where R₁ = R₂ = 1).

The question: What is the replacement resistance of the circuit below?

A hint : Click here!

The answer: Click here!