10-8
Map the interview terrain
- Practise two-science switching
- Use the ESAT module structure to organise revision
- Match ESAT modules to your strongest current subjects
Free Interview Resources
Cambridge Natural Sciences Interview Questions
Free practice questions, preparation advice, and expert insights for Natural Sciences interviews at Cambridge.
2 science-focused interviews · supervision-styleFormat
Sample Cambridge Natural Sciences Interview Questions
Real Natural Sciences interview questions in the style Cambridge asks. Try answering each one aloud before you reveal the hint.
01A 5 kg box is in a lift accelerating upwards at 4 m s^-2. Find the tension in the supporting rope, then explain what changes if a second identical box is attached beneath it by another rope.
Problem-Solving
mid
A 5 kg box is in a lift accelerating upwards at 4 m s^-2. Find the tension in the supporting rope, then explain what changes if a second identical box is attached beneath it by another rope.
Problem-Solving
Hint
Start with a free-body diagram and apply Newton's second law separately to each box.
02Two identical beakers sit on a balance. One contains a submerged steel ball suspended by a string from outside the beaker; the other contains a floating plastic ball. Which side is heavier, and why?
Problem-Solving
hard
Two identical beakers sit on a balance. One contains a submerged steel ball suspended by a string from outside the beaker; the other contains a floating plastic ball. Which side is heavier, and why?
Problem-Solving
Hint
Think about which object transfers its weight to the beaker and which transfers only the buoyant reaction force.
03An ice cube floats in a glass of water. When it melts, does the water level rise, fall or stay the same?
Problem-Solving
entry
An ice cube floats in a glass of water. When it melts, does the water level rise, fall or stay the same?
Problem-Solving
Hint
Use Archimedes' principle and compare the displaced water with the melted ice volume.
04Three identical capacitors are connected in series. Derive the equivalent capacitance and explain why it is smaller than the capacitance of any one capacitor.
Problem-Solving
mid
Three identical capacitors are connected in series. Derive the equivalent capacitance and explain why it is smaller than the capacitance of any one capacitor.
Problem-Solving
Hint
Use common charge in a series circuit and add the potential differences across each capacitor.
05A cube is made of identical resistors on each edge. How would you find the resistance between opposite corners?
Problem-Solving
hard
A cube is made of identical resistors on each edge. How would you find the resistance between opposite corners?
Problem-Solving
Hint
Look for symmetry: points at the same potential can be joined or separated without changing the current distribution.
Supervision-style interviews with problem-solving and academic discussion, often with two interviewers.
Cambridge interviews usually happen at your first-choice college. Most applicants have two interviews, with some subjects requiring a third at the pooled college. Cambridge interviews tend to involve two interviewers and may include a written assessment or pre-interview task sent on the day.
20-45 minutes per interview2 interviews at first-choice college, possibly 1 more if pooled
- -Cambridge often sends a pre-reading or stimulus material 20-30 minutes before the interview. Use that time wisely.
- -At Cambridge, you may be given a piece of paper and asked to work through a problem. Write clearly and explain as you go.
- -The supervision system at Cambridge is about collaborative learning, so interviewers want to see if you can be "taught" during the session.
Invitation → Decision: the interview timeline
Interview Invitation
Late Nov
Arrival to Interview
Early Dec
Technical Question
Mid Dec
Decision
Early Jan
Interview Invitation
Late Nov
Arrival to Interview
Early Dec
Technical Question
Mid Dec
Decision
Early Jan
Conceptual & Discussion
4 questions01What information does a rate equation give you, and how could you use experimental data to determine the order of reaction?
mid
Hint
Separate what is inferred from the balanced equation from what must be measured experimentally.
02Why is benzene usually drawn with a circle inside a hexagon, and what does that representation fail to show?
mid
Hint
Discuss delocalised electrons, equal bond lengths and the difference between a model and a literal structure.
03How can amino acids behave as both acids and bases?
mid
Hint
Identify the functional groups and think about proton donation and acceptance at different pH values.
04What problems do fish face by living underwater?
mid
Hint
Consider oxygen availability, osmoregulation, buoyancy, pressure, locomotion and sensory systems.
Personal Statement
3 questions01You wrote about measuring Planck's constant in your personal statement. Talk us through the experimental method and the main sources of uncertainty.
mid
Hint
Explain the apparatus first, then identify what was measured, what was inferred and where systematic error could enter.
02You mention a specific scientific experience in your personal statement. What did it change about the way you think about science?
entry
Hint
Avoid retelling the activity; focus on a concept, method or assumption you now understand differently.
03You have read about quantum computing. What physical problems do researchers face, and how are they trying to overcome them?
hard
Hint
Distinguish the idea of a qubit from the engineering problems of coherence, noise, error correction and scalability.
Curveball
2 questions01A rubbery ball is found on Mars. How would you decide whether it is alive?
hard
Hint
Start by defining operational criteria for life, then propose tests and possible false positives.
02Estimate the number of atoms in a Brussels sprout.
mid
Hint
Estimate mass, approximate composition as mostly water and organic material, then convert to molecules or atoms.
Ethical
2 questions01What drug might make someone a better marksman, and what scientific and ethical issues would you consider before answering?
hard
Hint
Separate physiological mechanisms such as tremor, heart rate and attention from safety, consent, fairness and misuse.
02A performance-enhancing drug could reduce tremor or anxiety in a high-pressure task. How would you decide whether it should be tested or allowed?
mid
Hint
Separate physiological evidence from medical safety, consent, fairness and possible misuse.
8-6
Rebuild core fluency
- Practise diagram-led explanations
- Keep algebra, graphs, proportionality and mechanics active
- Review the science subjects linked to your Biological or Physical stream
6-4
Train think-aloud problem solving
- Build a think-aloud habit
- Train estimation, not just exact calculation
- Explain assumptions, units and checks before committing to an answer
4-2
Pressure-test the personal statement
- Keep a personal-statement defence sheet
- Interrogate one supercurricular resource deeply
- Prepare factual, methodological and evaluative follow-ups for each major claim
2-0
Simulate interview conditions
- Practise receiving hints without panicking
- Practise switching between two science areas in one session
- Use hints to revise your route rather than restarting from memory
Cambridge Natural Sciences: Sample Interview Questions Across Disciplines
Cambridge NatSci interviews test your scientific reasoning across multiple disciplines. You may be given problems spanning physics, biology, and chemistry, often using unfamiliar contexts to see how you apply fundamental principles.
Q1. Why is ice less dense than water, and what would happen to life on Earth if it were denser?
How to approach this: Start with the chemistry: hydrogen bonding in water creates an open hexagonal lattice in ice, making it less dense. Then reason through the biology: if ice sank, lakes and oceans would freeze from the bottom up, eliminating aquatic habitats. Consider the feedback loops on global temperature and whether complex life could have evolved at all.
Q2. Estimate how many molecules you breathe in that were also breathed by Julius Caesar.
How to approach this: This is a Fermi estimation spanning physics and chemistry. Estimate the number of molecules in a single breath (~2.5 x 10^22), the total molecules in the atmosphere (~10^44), and assume Caesar's breaths have fully mixed over 2,000 years. The ratio gives a surprisingly high probability of overlap. Show your working and state assumptions clearly.
Q3. A patient has a genetic mutation that prevents them producing functional haemoglobin. What symptoms would you expect, and how might you treat them?
How to approach this: Start with the biology of haemoglobin: oxygen transport, the role of iron, and the quaternary structure. Predict symptoms from first principles (fatigue, pallor, organ damage from hypoxia). For treatment, reason through options: blood transfusions, gene therapy, and why a bone marrow transplant targets the root cause. Link to real conditions like sickle cell disease or thalassaemia.
Unlock the full guide
- The full Natural Sciences question bank, by category, with hints
- A week-by-week preparation roadmap
- The common mistakes that cost offers — and how to avoid them
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The Complete Cambridge Natural Sciences Interview Guide
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Cambridge Natural Sciences Interview Videos
University of Cambridge Natural Sciences overview
Official University of Cambridge overview video for Natural Sciences.
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Further Reading
Recommended Resources
Website
Cambridge Natural Sciences course page
by University of Cambridge
UCAS code BCF0; Natural Sciences, BA (Hons) and MSci; 3 or 4 years full-time; all Colleges.; A-level requirement A*A*A; IB requirement 41-42 with 776 at Higher Level.
Website
Cambridge ESAT admissions test page
by University of Cambridge
Cambridge applicants must take the first ESAT sitting, 12-16 October 2026.; Registration opens 20 July 2026 and booking closes 28 September 2026.
Website
Cambridge interview guidance
by University of Cambridge
Interviews are academic conversations assessing potential, subject understanding, independent thinking and readiness for Cambridge-style learning.; Main interview period for 2027 entry is 7-18 December 2026.
Website
Cambridge Undergraduate Admissions Statistics 2025 cycle
by University of Cambridge
Natural Sciences had 2,644 applications, 672 offers and 576 acceptances in the 2025 cycle.; Official Natural Sciences success rate for the 2025 cycle was 21.8%.
Website
Cambridge application decisions and contextual data pages
by University of Cambridge
Decisions consider academic record, reference, personal statement, written assessment, contextual data and interview performance.; Applications can be placed in the Winter Pool so other Colleges can consider them.
Frequently Asked Questions
Plan for two science-focused interviews where that pattern is used, but check your invitation carefully. Cambridge's general guidance says most applicants have 1 or 2 interviews totaling around 35 minutes to 1 hour, and some applicants have more depending on the subject and College.
The main Cambridge interview period for 2027 entry is 7 to 18 December 2026. Applicants placed in the Winter Pool may have an additional interview in mid-to-late January 2027.
Natural Sciences applicants take Mathematics 1 plus two modules chosen from Biology, Chemistry, Physics and Mathematics 2. Each module is 40 minutes, so the Natural Sciences ESAT sitting totals 120 minutes.
The official 2027-entry course page gives A*A*A at A-level and 41-42 points in the IB with 776 at Higher Level. Applicants must study Mathematics plus two other science or mathematics subjects.
No, Natural Sciences applicants are not usually asked to submit example written work. The current required pre-interview assessment is the ESAT.
Choose the stream that matches your current subjects and academic strengths. Cambridge says the stream and school subjects affect the types of interview questions asked, although your actual first-year subject choices are not made until you arrive.
The core admissions process is the same for all applicants, but international applicants should check equivalent qualifications, English-language requirements, test-centre arrangements and any additional documents such as transcripts.
Cambridge uses contextual data to understand achievement in context, but says it does not systematically lower offer grades or compensate for a poor academic record. It may contribute to holistic review, pooling and reconsideration.