What can be added to a parallel circuit to turn components on and off?

What can be added to a parallel circuit to turn components on and off?

• A. Switches
• B. Fuses
• C. Resistors
• D. Capacitors

Answer: (A)

Controlling current by opening and closing a circuit path is what a switch does. In a parallel circuit, each branch has its own path from the supply, so adding a switch in a branch lets you complete or interrupt that path. When the switch is closed, current flows and the component turns on; when opened, the path is broken and the component turns off, without affecting the other branches. A fuse protects against overcurrent by breaking the circuit if a fault occurs, not for manual on/off control. A resistor limits current but doesn’t provide a way to turn the component on or off. A capacitor stores charge and can influence timing, but it doesn’t serve as a simple on/off control. So the element that enables turning components on and off is a switch.

Controlling current by opening and closing a circuit path is what a switch does. In a parallel circuit, each branch has its own path from the supply, so adding a switch in a branch lets you complete or interrupt that path. When the switch is closed, current flows and the component turns on; when opened, the path is broken and the component turns off, without affecting the other branches. A fuse protects against overcurrent by breaking the circuit if a fault occurs, not for manual on/off control. A resistor limits current but doesn’t provide a way to turn the component on or off. A capacitor stores charge and can influence timing, but it doesn’t serve as a simple on/off control. So the element that enables turning components on and off is a switch.