Device for Identifying Electric Charge

The primary function is to detect the presence of electric charge on a conductor or object. Let's examine the options:

• Electroscope: This instrument is specifically designed to detect and indicate the presence of static electric charges. It works by observing the repulsion of two lightweight conductors (like gold leaves) when they are charged by induction or contact from the object being tested.
• Ohmmeter: Used to measure electrical resistance between two points in a circuit. It does not detect charge presence.
• Multimeter: A versatile device that measures multiple electrical quantities, typically voltage, current, and resistance. While it can measure voltage (related to charge potential), it doesn't directly identify the presence of charge in the way an electroscope does.
• Ampere meter (Ammeter): Used specifically to measure electric current (the rate of flow of charge). It doesn't detect the static presence of charge on an object.

Therefore, the Electroscope is the correct device for identifying the presence of electric charge on an object.