When an electric charge was moved in an electric field between points with a variety of potentials of 20 kV,

When an electric charge was moved in an electric field between points with a variety of potentials of 20 kV, the field forces performed work of 40 mJ. the amount of charge is …

Initial data: φ1 – φ2 (potential difference value, voltage) = 20 kV = 20 * 10 ^ 3 V; A (the work done by the field forces) = 40 mJ = 40 * 10 ^ -3 J.
The amount of charge can be determined from the formula: U = φ1 – φ2 = A / q, whence q = A / φ1 – φ2.
Let’s perform the calculation: q = 40 * 10 ^ -3 / (20 * 10 ^ 3) = 2 * 10 ^ -6 C = 2 μC.
Answer: The amount of charge is 2 μC.