Question Video: Evaluating the Output of an OR Gate Using a Truth Table | Nagwa Question Video: Evaluating the Output of an OR Gate Using a Truth Table | Nagwa

# Question Video: Evaluating the Output of an OR Gate Using a Truth Table Physics • Third Year of Secondary School

The truth table shows the output of an OR gate for various combinations of inputs. What is the value of π in the table? What is the value of π in the table?

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### Video Transcript

The truth table shows the output of an OR gate for various combinations of inputs. What is the value of π in the table?

Okay, so weβve got a truth table that shows the behaviour of an OR gate. Now an OR gate behaves in the following way. First of all, it has two inputs, input π΄ and input π΅, and one output.

Now, if either of the inputs π΄ or π΅ are one, then the output is one. Otherwise, the output for an OR gate is zero. Thatβs why itβs known as an OR gate. Because if either input π΄ or input π΅ is one, then the output ends up being one as well.

Now, using that information, we need to work out the value of π in the table. And π is the value of the output for when the value of input π΄ is zero and the value of input π΅ is one.

Now, in this case, one of the inputs is one. We can see that input π΅ is set to one. And so the value of π will be one as well.

Hence, that is our answer to this part of the question. The value of π in the table is one.

Moving on then, letβs look at the next part of the question, which says βWhat is the value of π in the table?β

Now, in the table, we can see that this is π. And this is the value of the output when input π΄ is set to one and input π΅ is set to one as well. Now, in this case, either input π΄ or input π΅ is one.

In fact, in this particular situation, both of them are one. And so the output which is the value of π is also going to be one.

And, therefore, the value of π in the table is one.

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