when a switch is closed that means
In switch language, open means to disconnect, or break the circuit. Some people call this turned off. Closed, is to connect, or make the circuit. Some people call this turne â¦ d on. In the case of a normally open switch, the switch is open (off) unless something takes action on the switch. Pushes a button for example, or holds a magnet near the switch, or other active force. A normally closed switch is closed (on) unless some force causes the switch to be opened.
A Direct Current circuit is a circuit that Electric Current flows through in one direction. DC is commonly found in many low-voltage applications, especially where these are powered by Battery. Most electronic circuits require a DC power supply. A Direct Electric Current flows only when the Electric Circuit is closed, but it stops completely when the circuit is open. A Switch is a device for making or breaking an Electric Circuit. While the Switch is closed, Figure 1(a), the circuit is closed and the Light Bulb turns On; while the Switch is opened, Figure 1(b), the circuit is open and the Light Bulb turns Off.