Question

4 which of the following is a device that can be used to control the flow of electrons in a circuit? a switch b voltmeter c light bulb d amp meter

Explanation:

To solve this, we analyze each option:

• Option A: A switch can open or close a circuit, thus controlling the flow of electrons (current). When closed, electrons flow; when open, they don't.
• Option B: A voltmeter measures voltage (potential difference) in a circuit, not control electron flow.
• Option C: A light bulb is a load (converts electrical energy to light/heat), not a control device.
• Option D: An ammeter measures electric current (rate of electron flow), not control it.

Answer:

A. Switch