Question

Two capacitors C₁ = 2μF and C₂ = 6μF in series, are connected in parallel to a third capacitor C₃ = 4μF. This arrangement is then connected to a battery of e.m.f. = 2 V, as shown in the fig. How much energy is lost by the battery in charging the capacitors ?

• A. $22 \times 10 ^ { - 6 } J$
• B. $11 \times 10 ^ { - 6 } J$
• C.
• D. $\left( \frac { 16 } { 3 } \right) \times 10 ^ { - 6 } J$

Answer 1

Answer: (B)

$11 \times 10 ^ { - 6 } J$

Answer 2

Equivalent capacitance

$C _ { e q } = \frac { C _ { 1 } C _ { 2 } } { C _ { 1 } + C _ { 2 } } + C _ { 3 } = \frac { 2 \times 6 } { 8 } + 4 = 5.5 \mu F$∴