Final answer:
Grounding connects a conductive object to the earth to fix it at zero volts, ensuring safety by allowing excess charge to be dissipated into the earth and preventing electric shocks.
Step-by-step explanation:
One purpose of grounding is to ensure that a conductive object is electrically connected to the primary structure of the earth, thereby fixing it at zero volts. This is done by connecting the object to the ground with a good conductor. When an object is grounded, it allows for the transfer of charge to and from the earth, which acts as a vast reservoir. Grounding helps in maintaining the safety of electrical systems by ensuring that any excess charge can be safely dissipated into the earth. This can prevent electric shocks from electrical appliances, as their metal cases can be ensured to be at zero volts relative to the earth, decreasing the risk of electric shock.