Helen has just had a shock. she got up from a plastic chair to open the door and got an electric shock when she touched the door handle.
i) How did she become charged?
ii) Why did she feel a shock when she touched the door handle?
2 answers
Helen rubbed the chair as she stood up and that created a charge on her body opposite to the charge on the chair. She discharged to the door handle when she touched it and that created the shock.
As a note, some materials have a varying affinity for electrons, and can acquire a charge when rubbed with another material.