Answer: Capacitors C1 and C2 are connected in parallel configuration.
Explanation: Charge stored in a capacitor is calculated by the relation between capacitance of the capacitor and voltage applied across its terminals as:
[tex]Charge (Q) = Capacitance (C) \times Voltage (V)[/tex]
Capacitance of capacitor-1 (C1) = 2 [tex]\mu F[/tex]
And the charge stored in it is 20[tex]\mu C[/tex]
By using above relation, voltage applied across the terminals of C1 is:
Voltage = [tex]\frac{Charge}{Capacitance}[/tex] = [tex]\frac{20}{2}=10V[/tex]
Actual voltage source connected across the combination of capacitors is 10 V and it is the same voltage required across the C1 to store 20[tex]\mu C[/tex] charge in it.
Voltage across both the capacitors is same if connected in parallel configuration and charge stored in the capacitors is same if connected in series configuration.
Hence, capacitors C1 and C2 are connected in parallel configuration.