IBM A1000-088 - Assessment: Foundations of Quantum Computing Practice Exam 2025: Latest Questions

A researcher measures a single qubit that is prepared in the state |+> = (|0> + |1>)/sqrt(2). What outcome distribution should they expect over many repeated measurements in the computational (Z) basis?

In IBM Quantum circuit diagrams, which gate is used to create an equal superposition from the |0> state?

A developer wants to run the same circuit many times to estimate measurement probabilities on IBM Quantum. Which concept most directly controls the number of repeated runs of the circuit?

A business stakeholder asks where quantum computers are most promising today. Which statement best reflects a realistic near-term use case?

A student builds a Bell-state circuit: apply H on qubit 0, then CNOT with control qubit 0 and target qubit 1, then measure both in the Z basis. What results should they typically observe?

A team compares results from an ideal simulator and real IBM Quantum hardware for the same circuit and sees lower success probability on hardware. Which is the most likely cause?

A circuit contains a CNOT between two qubits that are not directly connected on the selected IBM Quantum backend. What is the most appropriate expectation?

A data scientist wants to use a hybrid approach where a classical optimizer updates parameters of a quantum circuit based on measured outcomes (e.g., VQE-style workflows). Which description best matches this pattern?

A learner claims: "Because a qubit can be in a superposition of 0 and 1, it can store both values at once and therefore gives an automatic 2x speedup per qubit for any computation." Which response is most accurate?

A circuit is intended to estimate the expectation value of Z on a qubit (i.e., <Z>) using measurement results in the computational basis. The learner instead measures counts of 0s and 1s and reports <Z> as (count(0)+count(1))/shots. What is the correct way to compute <Z> from Z-basis measurement outcomes?

A learner measures a single qubit prepared in the state |+> in the computational (Z) basis. What measurement outcome distribution should they expect over many shots?

Which statement best describes why Qiskit uses "shots" when running a circuit on a simulator or IBM Quantum hardware?

A team wants to demonstrate quantum advantage concepts to business stakeholders using a simple, near-term-friendly application. Which use case is most appropriate for a foundational demonstration on current noisy devices?

A circuit is intended to create a Bell state and then measure both qubits. The developer applies H on qubit 0, then CX with control=0 and target=1, and measures both in the Z basis. Which result pattern most strongly indicates successful entanglement (ignoring noise)?

A user submits a job to an IBM Quantum backend and receives results where the bitstrings appear reversed from what they expected (e.g., they expected 01 but see 10). What is the most likely explanation and best practice to address it?

A developer needs to run the same circuit on a specific IBM Quantum device. After transpilation, the circuit depth increases significantly and performance worsens. What is the most likely cause?

A team is deciding between using Grover's algorithm or a variational algorithm for a near-term search/optimization problem on current IBM Quantum hardware. Which consideration most strongly favors a variational approach?

A learner claims: "If I apply an X gate twice, I will get a different quantum state because quantum gates are irreversible." Which response is correct?

A circuit includes mid-circuit measurements whose results are used to conditionally apply later gates (dynamic circuits). The job runs successfully on a simulator but fails or is unsupported on the chosen hardware backend. What is the best next step?

A researcher wants to estimate the expectation value of a Hamiltonian that is a sum of non-commuting Pauli terms. They notice high variance and long runtimes due to many measurement settings. Which approach is most appropriate to reduce measurement overhead while preserving correctness in a foundational setting?

A developer runs a circuit on a real IBM Quantum backend and gets different bitstring counts each time, even though the circuit was not changed. Which explanation best describes why this happens?

You need to verify that two qubits are entangled in an introductory experiment. Which circuit pattern is the standard way to create a Bell state from |00>?

A team wants to mitigate readout errors when executing circuits on a real IBM Quantum device. Which approach is a recommended practice in Qiskit experiments?

A user builds a circuit with mid-circuit measurement and a conditional operation (e.g., apply X if the measured bit is 1). The circuit runs in simulation but fails to execute on a chosen hardware backend. What is the most likely cause?

A project is evaluating near-term quantum advantage for optimization. They consider using QAOA and also a classical heuristic baseline. Which statement best reflects a sound best practice for foundational evaluation?