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1
The fan put of a 7400 NAND gate is
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Answer: Option D
Solution:
Let's break down this question about the fan-out of a 7400 NAND gate!

First, let's understand the key terms:

1. 7400 NAND gate: This is a very common type of digital logic chip. It belongs to a family of chips called TTL, which stands for Transistor-Transistor Logic. The "74" in 7400 indicates it's a part of the standard 74-series TTL family.

2. Fan-out: Imagine you have one digital gate, like our NAND gate, and it's sending its output signal to the inputs of other gates. The fan-out is simply the maximum number of other gates' inputs that a single output gate can reliably drive without its signal getting too weak or distorted. If you connect too many gates, the output gate might not be able to supply enough electrical current, which could lead to incorrect voltage levels and make the other gates malfunction.

3. TTL (Transistor-Transistor Logic): This refers to a specific type of electronic circuitry used to build integrated circuits (chips) like the 7400. When we talk about fan-out in the context of TTL, we often specify it in terms of "TTL loads" or "TTL inputs." One "TTL load" means the input of one standard TTL gate.

Now, let's answer the question:

For standard 74-series TTL gates (like the 7400 NAND gate), the standard or typical fan-out is 10. This means that one 7400 NAND gate can safely drive the inputs of up to 10 other standard TTL gates without any issues regarding signal integrity.

Therefore, the fan-out of a 7400 NAND gate is 10 TTL.

The correct answer is Option D: 10TTL.
2
The universal gate is ___________
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Answer: Option A
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3
An OR gate has 6 inputs. The number of input words in its truth table are
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Answer: Option C
Solution:
A truth table shows all possible combinations of inputs and the corresponding output of a logic gate.

For a gate with 'n' inputs, the number of possible input combinations (or input words) is calculated as 2 raised to the power of n (2n).

In this case, the OR gate has 6 inputs.

So, the number of input words in its truth table is 26 = 2 * 2 * 2 * 2 * 2 * 2 = 64.
4
In which of the following base systems is 123 not a valid number?
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Answer: Option D
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5
In case of OR gate, no matter what the number of inputs, a
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Answer: Option A
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6
The number of Boolean functions that can be generated by n variables is equal to
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Answer: Option B
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7
Which mechanism allocates the binary value to the states in order to reduce the cost of the combinational circuits?
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Answer: Option C
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8
Positive logic in a logic circuit is one in which
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Answer: Option D
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9
Digital circuit can be made by the repeated use of ___________
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Answer: Option C
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10
Pick out the CORRECT statement:
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Answer: Option C
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