What charge is left on a Jumper?

A jumper typically has no charge left on it when not connected to a power source. However, if it has been used in a circuit, it may have a small residual charge due to capacitive effects. In electronic terms, a jumper is simply a conductive bridge, and any charge present would dissipate quickly once the circuit is disconnected. Always exercise caution and ensure that circuits are discharged before handling components.