Question

Two capacitors of unknown capacitances C₁ and C₂ are connected first in series and then in parallel across a battery of 100 V. If the energy stored in the two combinations is 0.045 J and 0.25 J respectively, determine the value of C₁ and C₂. Also calculate the charge on each capacitor in parallel combination.

Answer 1

Energy stored in a capacitor, E = \(\cfrac12\)CV²

Solving (iii) and (iv) C₁ = 38.2 µF

C₂ = 11.8 µF

In parallel Q₁ = C₁ V

= 38.2 × 10^–6 × 100 = 38.2 × 10^–4 C

Q₂ = C₂ V

= 11.8 × 10^–6 × 100 = 11.8 × 10^–4 C