A potential divider circuit is shown in figure. The output voltage V₀ is :

Solution

Physics sir · 4 steps

All resistors are in series, so find the one current first, then multiply by the resistance between the taps.

1. Total resistance. The 3.3 kΩ resistor and the seven 100 Ω resistors are all in series. The total is 3300 + 7 × 100 = 4000 Ω.
2. Current in the chain. The output leads draw no current, so the same current flows through every resistor: I = (4 V)/(4000 Ω) = 1 mA.
3. Resistance across output. The tap sits after the third resistor, so V₀ is taken across the last five 100 Ω resistors. That is 500 Ω.

   V₀ = I R = (1 × 10⁻³ A)(500 Ω) = 0.5 V

4. So. The output voltage is 0.5 V, option (c).

The idea to keep. In a potential divider the voltage splits in proportion to resistance: V₀ = V × R_(tapped)/Rₜₒₜₐₗ. Count carefully which resistors lie between the output terminals.

Answer from the NTA final answer key. Solution by PrepWiser.