Which one is on, 'on' or 'off'?
2 Answers
Between 'on' and 'off', 'on' means to turn on, while 'off' means to turn off. These two terms are commonly found on car start buttons or on the car air conditioning panel. Adjusting to the 'on' position indicates that a certain function is activated, and adjusting to the 'off' position means that the function is deactivated. A switching power supply is a type of power supply that uses modern power electronics technology to control the ratio of the switch tube's on and off times to maintain a stable output voltage. Switching power supplies are generally composed of a pulse width modulation control IC and MOSFET. Compared to linear power supplies, the costs of both increase with the increase in output power, but their growth rates differ.
I often help beginners learn to drive, and every time I teach them how to operate a vehicle, I encounter this question: 'Which is on and which is off?' My explanation is simple: on means open, and off means closed. In a car, when you turn the headlight switch to the on position, the lights come on, and when you switch it to off, the lights go out. Beginners often get confused, especially when some buttons in the car are labeled with tiny letters that are hard to see, leading to mistakes. For example, when driving at night, if you accidentally switch to off and the lights are off, the road ahead becomes pitch black, and you might hit roadside obstacles or other vehicles—how dangerous that would be! I once taught a student who forgot to turn on the headlights while driving on the highway and almost had an accident. So, I suggest that when buying a car, you familiarize yourself with the switch positions. On most cars, the left control lever has markings: red for off and green for on. Make it a habit to check the light status before starting the car every time—safety first.
