# Video: Evaluating the Output of NOT Gates

The diagram shows a NOT gate. If the input is 0, what will the output be?

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### Video Transcript

The diagram shows a NOT gate. If the input is zero, what will the output be?

Okay, so, in this diagram, we’ve been shown a NOT gate, otherwise known as an inverter. And the reason that a NOT gate is known as an inverter is because it takes whatever the input is and inverts it so that we get the output. In other words, the truth table of a NOT gate looks something like this.

The NOT gate has a single input and a single output. And when the input is zero, the output is one. And when the input is one, the output is zero. In other words, whatever the input is, the output is not that. That’s why it’s called a NOT gate.

And so, in this particular question, we’ve been told that the input is zero. And we need to find out what the output is. So, based on the truth table, we can see that when the input is zero, the output is one. And that is the answer to our question.