Selected MCQ

Current Question
What is a quantum bit or qubit?
  • A. A byte in a quantum computer
  • B. A classical bit encoded with superconductors
  • C. The basic unit of quantum information that can be in a superposition
  • D. A binary digit stored in memory
Correct Answer: C
Explanation:
A qubit is a quantum version of a bit that can exist in a superposition of 0 and 1 states.
Related Question 1
What is a key feature of quantum computing that offers computational advantages?
  • A. Using vacuum tubes
  • B. Superposition and entanglement
  • C. Fiber optic circuits
  • D. DC power only
Correct Answer: B
Explanation:
Quantum superposition and entanglement enable certain calculations to be done much faster.
Related Question 2
What is a major challenge in large-scale quantum computing today?
  • A. Lack of electricity
  • B. Qubit decoherence and error rates
  • C. Too much classical memory
  • D. No known algorithms
Correct Answer: B
Explanation:
Keeping qubits coherent and reducing errors are key challenges in building large quantum computers.
Related Question 3
What is a key feature of quantum computing that can offer speedups?
  • A. Using vacuum tubes
  • B. Superposition and entanglement
  • C. Fiber optic circuits
  • D. DC power only
Correct Answer: B
Explanation:
Quantum superposition and entanglement enable parallelism that can speed up tasks like factoring.
Related Question 4
Which technology helps secure communications using quantum mechanics?
  • A. Quantum key distribution (QKD)
  • B. Standard VPN
  • C. Hashing
  • D. WPA2
Correct Answer: A
Explanation:
QKD uses quantum particles to securely share encryption keys, with eavesdropping detectable.
Related Question 5
How many states can a qubit theoretically exist in at once?
  • A. 2
  • B. Many via superposition
  • C. 1
  • D. Infinite
Correct Answer: B
Explanation:
A qubit can exist in a superposition of states, effectively representing multiple values simultaneously.