A capacitor \( C_1 \) of capacitance \( 5\,\mu\text{F} \) is charged to a potential of \( 30\,\text{V} \) using a battery. The battery is then removed and the charged capacitor is connected to an uncharged capacitor \( C_2 \) of capacitance \( 10\,\mu\text{F} \) as shown in figure. When the switch is closed charge flows between the capacitors. At equilibrium, the charge on the capacitor \( C_2 \) is ____________ \( \mu\text{C} \).
