To what voltage must a 20 μF capacitor be charged in order to charge it and obtain 1 J of energy.

Initial data: C (electrical capacity of the capacitor) = 20 μF = 20 * 10 ^ -6 F; Wp (energy that must be obtained when charging a capacitor) = 1 J.
The voltage to which it is necessary to charge the capacitor is determined from the formula: Wp = C * U ^ 2/2, whence U = √ (2Wp / C).
Let’s do the calculation: U = √ (2 * 1/20 * 10 ^ -6) = 316.2 V.
Answer: The capacitor must be charged to a voltage of 316.2 V.