A 100 μF capacitor is charged to a potential difference of 24V. It is connected to an uncharged capacitor of capacitance 20 μF. What will be the new potential difference across the 100 pF capacitor?
Given
for charged capacitor C1 =100μF
V=24V
Formula used :
Charge is given by the formula
Q=CV
Where
Q is the charge of the capacitor
C is the capacitance of the capacitor
V is the voltage across the capacitor
Putting the values in the above formula, we get
This capacitor is connected to an uncharged capacitor of C2=20μF
When a charged capacitor is connected to an uncharged capacitor, then the total charge will be equal to
The potential difference across both capacitors will be the same.
Substitute in eq1)
New potential difference is = 
If 100 μF capacitor which is charged to 24V is connected to an uncharged capacitor of 20 μF then potential difference across it is 20V.