A capacitor with a capacity of C = 100 μF is charged to a potential U = 90 kV. Determine its charge.

C = 100 μF = 100 * 10 ^ -6 F.
U = 90 kV = 90 * 10 ^ 3 V.
Q -?
According to the definition, the electric capacity of the capacitor C is determined by the formula: C = Q / U, where Q is the electric charge on the capacitor plates, U is the voltage between the plates or the potential difference between them.
Q = C * U.
Q = 100 * 10 ^ -6 F * 90 * 10 ^ 3 B = 9 Cl.
Answer: on the capacitor plates there is a charge of Q = 9 C.