Excellent Automata Theory Test - 34+ MCQs: Automata Theory test: Evaluate Your Understanding with Automata Questions and Answers

1. What is the primary difference between DFA and NFA?

NFA has more states

NFA can have ε-transitions

DFA always halts

DFA is more complex

2. Which of the following is not a component of a Pushdown Automaton?

Stack

Input Tape

Finite Control

Head

3. Which automaton has a stack?

Pushdown automaton

Turing machine

Finite automaton

DFA

4. What is the primary limitation of deterministic context-free languages?

They cannot parse ambiguous grammars efficiently

They can only recognize regular languages

They are not expressive enough to represent all formal languages

They cannot be used to define context-free grammars

5. What does the Church-Turing thesis propose?

Every effective computation can be carried out by a Turing machine

Every Turing machine can be simulated by a deterministic finite automaton

Every context-free language can be recognized by a pushdown automaton

Every context-sensitive language can be recognized by a linear-bounded automaton

6. In which automaton, the output depends on the current input and the current state?

DFA

NFA

Turing machine

Pushdown automaton

7. What does the Chomsky hierarchy classify?

Languages based on their complexity

Automata based on their processing power

Turing machines based on their operations

Grammars based on their derivations

8. Which of the following problems is not decidable?

Determining if a given Turing machine accepts a given input

Determining if two regular languages are equal

Determining if a given Turing machine halts on all inputs

Determining if a given context-free grammar is ambiguous

9. In the context of automata theory, what is the purpose of the transition function?

To determine the initial state

To define the input alphabet

To specify the set of final states

To describe the state transitions based on inputs

10. Which of the following is a characteristic of recursively enumerable languages?

They are always decidable

They can be accepted by a Turing machine

They are always regular

They have a finite number of strings

11. Which of the following is a characteristic of context-free grammars?

They can be parsed by a deterministic pushdown automaton

They can generate all regular languages

They can generate Turing-complete languages

They are always unambiguous

12. What does the Pumping Lemma for regular languages state?

Every regular language can be generated by a regular expression

Every regular language can be recognized by a deterministic pushdown automaton

Every sufficiently long word in a regular language can be 'pumped' to generate more words in the language

Every regular language is finite in length

13. What does the halting problem state?

It is undecidable whether a given Turing machine halts on all inputs

Every Turing machine halts on every input

There exists a Turing machine that halts on no inputs

Every Turing machine halts on some input

14. What is the primary purpose of a deterministic finite automaton (DFA)?

To recognize regular languages

To recognize context-free languages

To recognize context-sensitive languages

To recognize Turing-complete languages

15. Which automaton is the most powerful?

Pushdown automaton

Turing machine

Finite automaton

Linear bounded automaton

16. What is the main focus of Automata Theory?

Algorithms and data structures

Hardware design

Study of abstract machines and computational problems

Operating system principles

17. Which automaton type is more expressive: deterministic or non-deterministic?

Deterministic Finite Automaton (DFA)

Non-Deterministic Finite Automaton (NFA)

Both are equally expressive

Neither can recognize any language

18. What is the primary purpose of a Turing Machine?

Recognize context-free languages

Recognize regular languages

Simulate any computer algorithm

Recognize deterministic languages

19. What is the significance of the hierarchy theorem in formal languages?

It demonstrates the existence of languages that cannot be recognized by machines of a certain type

It establishes a hierarchy of Turing machines based on computational power

It proves that every context-free language is also regular

It defines the limits of regular expressions

20. In automata theory, what does ε denote?

An empty string

A non-empty string

A single character

An infinite string

21. What is an automaton in computer science?

A software for data processing

A mathematical model of computation

A programming language feature

A type of data structure

22. What is the purpose of formal languages in Automata Theory?

To write programs

To study patterns in strings

To design operating systems

To build networks

23. What is the primary difference between a deterministic pushdown automaton (DPDA) and a non-deterministic pushdown automaton (NPDA)?

A DPDA always makes a deterministic choice, while an NPDA may make non-deterministic choices

An NPDA always makes a deterministic choice, while a DPDA may make non-deterministic choices

A DPDA has more states than an NPDA

An NPDA can accept a wider range of languages than a DPDA

24. In the context of computational models, what is a polynomial-time algorithm?

An algorithm whose worst-case running time is bounded by a polynomial function of the size of the input

An algorithm that runs in constant time

An algorithm that runs in logarithmic time

An algorithm that runs in exponential time

25. In formal language theory, what does the pumping lemma describe?

The structure of regular expressions

The properties of context-free grammars

The properties of regular languages

The properties of context-sensitive languages

26. What does ε-transitions represent in NFA?

An empty string transition

An error state

An end of input

A loop

27. What is the pumping lemma used for in formal language theory?

Proving languages are not regular

Proving languages are regular

Proving languages are context-free

Proving languages are context-sensitive

28. Which automaton recognizes a regular language?

Pushdown automaton

Turing machine

Finite automaton

Linear bounded automaton

29. Which automaton has the most computational power?

Deterministic Finite Automaton

Pushdown Automaton

Turing Machine

Nondeterministic Finite Automaton

30. In the context of automata theory, what is a state's dominance?

A state from which all other states can be reached

A state that cannot be reached from any other state

A state that is always the starting state

A state that has the most transitions

Automata Theory MCQ Test 1