Excellent Automata Theory Test - 35+ MCQs: Automata Theory test: Evaluate Your Understanding with Automata Questions and Answers

1. 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

2. 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

3. 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

4. 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

5. 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

6. Which automaton is the most powerful?

Pushdown automaton

Turing machine

Finite automaton

Linear bounded automaton

7. 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

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

Recognize context-free languages

Recognize regular languages

Simulate any computer algorithm

Recognize deterministic languages

9. Define a decidable language in the context of Turing machines.

A language for which there exists a Turing machine that accepts all strings

A language that can be recognized by a non-deterministic Turing machine

A language that has a unique Turing machine

A language that cannot be recognized by any Turing machine

10. 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

11. 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

12. Which automaton recognizes a regular language?

Pushdown automaton

Turing machine

Finite automaton

Linear bounded automaton

13. 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

14. What does ε-transitions represent in NFA?

An empty string transition

An error state

An end of input

A loop

15. 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

16. In automata theory, what does ε denote?

An empty string

A non-empty string

A single character

An infinite string

17. Which type of automaton is used to recognize regular languages?

Deterministic Finite Automaton (DFA)

Pushdown Automaton (PDA)

Turing Machine

Nondeterministic Finite Automaton (NFA)

18. 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

19. Which of the following is a property of regular languages?

Closure under intersection

Closure under complementation

Closure under concatenation

Closure under reversal

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

Stack

Input Tape

Finite Control

Head

Automata Theory MCQ Test 2