Static Electricity - Mission SE7 Detailed Help

A negatively charged piece of styrofoam is placed on the table. A neutral aluminum plate is brought near as shown below. While held above the styrofoam, the aluminum plate is touched (grounded). The ground is removed, while the aluminum pie plate is still above the styrofoam, as shown. The aluminum pie plate is being charged by the method of ____.

Methods of Charging:
There are three methods of charging that are commonly discussed in a static electricity unit - charging by friction, charging by conduction (or contact), and charging by induction.

Triboelectric charging (Charging by friction) usually involves the rubbing of two objects together.

Charging by conduction (or contact) involves the touching of a charged object to a neutral object.

Charging by induction involves bringing a charged object near to but not touching a neutral object in order to polarize the object and then charging it by momentarily connecting it to a ground.