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Quantum Computing quiz

All 10 questions. After you submit, each question shows the right answer and why. Back to the quick check

ExplorerQuestion 1 of 10

Unlike an ordinary bit, a qubit can be in a mix of 0 and 1.

True

False

ExplorerQuestion 2 of 10

Why are qubits so hard to look after?

They only work in sunlight

Tiny disturbances such as stray magnetic fields or temperature changes can spoil them

They run out of battery very quickly

They are too big to fit in a computer

InvestigatorQuestion 3 of 10

Each extra qubit doubles the number of 0-and-1 combinations a set of qubits can hold in superposition. How many combinations can 5 qubits hold?

Your answer

InvestigatorQuestion 4 of 10

A quantum computer solves problems by trying every possible answer at the same time and then reading out the best one.

True

False

ScientistQuestion 5 of 10

What did Peter Shor's 1994 quantum algorithm show could be done quickly on a large quantum computer?

Factoring very large numbers that are products of huge primes

Storing unlimited data in one qubit

Predicting the weather exactly

Sorting a list faster than any classical method

ScientistQuestion 6 of 10

What did NIST release on 13 August 2024?

A ban on public-key encryption

A proof that quantum computers can never work

Its first three finalised post-quantum cryptography standards

The first quantum computer with a million qubits

ScientistQuestion 7 of 10

Which statement about two leading kinds of qubit matches NIST's description?

Trapped-ion qubits hold superpositions a long time but compute slowly; superconducting qubits are fast but more fragile

Superconducting qubits work best at room temperature

Trapped-ion qubits are made from ordinary computer memory chips

Both kinds are immune to errors

AdvancedQuestion 8 of 10

Suppose each quantum operation independently has a 1-in-1000 chance of error. What is the probability that a computation of 500 operations has no error at all? Give your answer to two decimal places.

Your answer

AdvancedQuestion 9 of 10

Why do researchers think quantum error correction will be essential, and why is it not a quick fix?

Your answer

ExpertQuestion 10 of 10

Critically assess the claim: 'Once quantum computers are large enough, every hard computational problem will become easy.'

Your answer