Solving a problem in physics section 72 point 100 elect

100. An electrostatic field is created in a vacuum by a charge Q. At a point located at a distance r = 30 cm from it, a force F = 1 μN acts on a charge Q0 = 5 nC. Determine: 1) the field strength E at the point where the charge Q0 is located; 2) charge Q.