A dynamic method of measuring the charge induced on a conductor

A simple method of measuring the charge induced on a conductor is presented. The method is based on the idea that a charged projectile passing near a conducting object will cause surface charges to be dynamically induced on its surface. By suitably arranging a detector in the surface of the object, the charge drawn onto the conductor during the passage of the charged projectile can be measured and related to the induced surface charge density. The charge is computed by integrating the current waveform. The concept has been used to design a detector that measures the charge induced on a high‐speed projectile such as a pellet fired from an air rifle, the charge induced on a raised hemispherical boss by a uniform electric field, and the surface charge induced on a flat plate by a point charge.