King's College Cambridge Natural Sciences Interview
What to expect and how to prepare for King's Natural Sciences interviews in 2026
Nearest pack: Biological Sciences — £180What to expect and how to prepare for King's Natural Sciences interviews in 2026
Nearest pack: Biological Sciences — £180King's College Cambridge is one of the university's most distinctive institutions — famous for its chapel, its choir, and its strong tradition in the arts and humanities, but also home to a rigorous and intellectually vibrant Natural Sciences community. King's NST supervisors take the same problem-led, reasoning-focused approach that characterises Cambridge science supervision across the board, but the college's culture of genuine intellectual breadth means that interview discussions frequently extend beyond strict disciplinary boundaries. Candidates who can think across subjects — who can see how a principle in one science connects to a question in another — tend to perform particularly well at King's. We do not publish a Natural Sciences pack — the Biological Sciences pack, £180, is the nearest fit.
Natural Sciences at Cambridge is unusual among British science degrees in being genuinely interdisciplinary in its first year. All NST students take courses in three or four sciences simultaneously, only beginning to specialise in Year 2. This means King's supervisors are assessing you not for depth in a single subject but for scientific reasoning ability across physics, chemistry, biology, and mathematics. Candidates who have prepared narrowly for one discipline may be surprised to find their King's interview covering territory from multiple sciences.
Natural Sciences applicants at King's typically have two interviews — one at King's and one at a second college through the pooling process. Each interview lasts approximately 25 to 35 minutes. King's NST interviews are problem-based: supervisors present questions, diagrams, data, or experimental scenarios and ask you to reason through them. The approach is consistent with the supervision format — you are expected to think aloud, engage with hints, and persist when problems are difficult.
The ESAT (Engineering and Science Admissions Test (ESAT)) is used to shortlist NST candidates, and strong ESAT performance — particularly in the physics and chemistry sections — is important for securing a King's interview. The ESAT tests exactly the kind of multi-disciplinary scientific reasoning that King's supervisors assess in interviews.
Pooled interviews, and the pack that covers both
The packs that cover Natural Sciences span physics, chemistry, biology and the mathematics underneath them — osmosis and water potential, orbital periods, designing a speed-of-sound experiment — which is the only sensible preparation when the second interview is at a college you did not pick. Each pack is £180 with model answers throughout, and Biological Sciences, the chemistry packs and Dynamics and Fields each have a free sample showing the format before you buy. NatSci spans three pack families — biological sciences, the chemistry packs, and dynamics and fields — so a candidate covering their three tracks reaches the 20% bundle tier.
Browse the subject packsOne interview at King's, one at a college you did not choose
The pooling arrangement means Natural Sciences applicants face two sets of supervisors with different habits, and the second is unknown until shortly before it happens. Preparing for King's alone leaves half the day unprepared.
Preparing around one college's habits is the trap, and the packs that cover Natural Sciences work the full range instead, £180 each, which has the side effect of exposing the science you are least comfortable with before a stranger does.
Prepare across your chosen science subjects, not just the one you find easiest or most familiar. King's supervisors will move between disciplines during an interview, and candidates who have strong foundations across multiple sciences consistently perform better than those who have prepared deeply in one area only.
Develop the habit of explaining scientific phenomena from first principles rather than reciting explanations you have memorised. King's supervisors frequently ask “why” questions that require genuine mechanistic understanding: not “what is osmosis” but “why does water move across a semi-permeable membrane in this direction, and what would happen if you changed the temperature?” Building the habit of asking yourself “why does this happen at the level of particles and forces?” for every phenomenon you study is excellent interview preparation.
Work through ESAT past papers and understand every question you find difficult. The ESAT tests multi-disciplinary scientific reasoning in a format that directly parallels what you will encounter at interview.
Interleave your revision instead of blocking it by subject: work through a chemistry mechanism, then a physics derivation, then a biology process, and notice how often the same underlying idea — equilibrium, gradient, conservation — turns up wearing a different subject's vocabulary. Physical chemistry, thermodynamics and mechanics share more structure than A-level teaching tends to show, and noticing that structure under interview conditions is closer to what a pooled King's interview actually rewards than an hour spent entirely inside one science. Past ESAT papers are useful here precisely because they force the same switching between disciplines within a single sitting.
The satellite question on the list above sounds like something you could settle by instinct in one sentence. Most candidates try exactly that, and most of them are wrong before they reach a full stop.
Question: if you doubled the mass of a satellite already in a stable circular orbit, what would happen to its orbital period?
A natural first answer reaches for Newton's second law: F = ma, so a satellite with twice the mass needs twice the force to keep producing the same acceleration. Gravity is also proportional to mass, so doubling the satellite's mass doubles the gravitational pull the planet exerts on it as well — the two doublings look like they cancel each other out, leaving the orbit unchanged at the same speed and the same period. Say that out loud, though, and a supervisor will ask a single question back: how do you know the speed stays the same, rather than assuming it? The intuition has reached the right-sounding conclusion without deriving it, and a King's interview is testing the derivation, not the conclusion.
Hints: write down the two forces that must balance for a circular orbit to hold: the gravitational force pulling the satellite inward, and the centripetal force needed to keep something moving in a circle rather than flying off in a straight line. Put the satellite's mass into both expressions explicitly, as a symbol, rather than reasoning about it in words, and watch what happens to that symbol once you actually do the algebra. If the working ever produces an equation where the satellite's mass has to matter for the orbit to make sense, that is a sign to go back and check a line, not a sign that the physics is unusually subtle.
Worked answer: gravity supplies the centripetal force, so GMm/r² = mv²/r, where M is the mass of the planet, m is the mass of the satellite, r is the orbital radius, and v is the orbital speed. The satellite's mass m sits on both sides of that equation and cancels immediately, leaving GM/r² = v²/r, which rearranges to v² = GM/r. Orbital speed depends only on the planet's mass and the radius of the orbit — the satellite's own mass has already dropped out and plays no part in the answer. Converting speed to period with v = 2πr/T gives (2πr/T)² = GM/r, which rearranges again to T² = 4π²r³/(GM). The satellite's mass does not appear anywhere in that final expression either. Doubling it, halving it, or replacing the satellite with one a hundred times heavier at the same orbital radius gives exactly the same orbital period, because the two effects the first-instinct answer described — more gravitational pull, more force needed to turn a heavier mass — are not merely similar in size. They are algebraically identical, so they cancel completely rather than leaving any residual change in speed or period behind.
None of that required anything beyond the A-level syllabus — it is Newton's second law and Newton's law of gravitation, combined and then simplified by watching a variable disappear rather than assuming what it does. The habit worth building is refusing to trust an answer that merely feels balanced until the algebra has actually produced that balance, because “the two effects cancel” is only true here as a result of a genuine mathematical coincidence: both force laws are exactly first-order in mass. Change the question slightly and the answer changes completely — ask what happens to the period if you double the planet's mass instead of the satellite's, and M does not cancel out of T² = 4π²r³/(GM) the way m did, so the period does change.
A supervisor is not listening for whether a candidate already knows that orbital period is independent of a satellite's mass; plenty of physics specialists have simply memorised that result. They are watching whether a candidate notices their own smuggled assumption once asked to show the working, and whether they can then apply the same reasoning to a follow-up question — what if it's the planet's mass that changes — without being walked through it a second time.
The packs that cover Natural Sciences are built the same way — question first, a layer of guidance behind it, a full worked answer behind that — and the walkthrough above simply borrows that shape for a physics question, since a pooled interview will not tell you in advance which of your three sciences it plans to test.
For free samples in nine subjects and the full expert packs at £180, see our Cambridge Natural Sciences interview questions resource.
Practice with tutor-written interview questions
Download the free Biology sample to see the format, or get the full Biology expert pack with worked model answers for £180.
See the expert packs →Straight to payment — no account, instant download.
Most Natural Sciences applicants take at least two science A-levels and Mathematics. Physics and Chemistry with Mathematics is a very common combination for physical NST; Biology and Chemistry with Mathematics for biological NST. King's does not specify exact A-level requirements, but you should be prepared to be assessed across multiple sciences in your interview regardless of your specific combination.
The ESAT is used by Cambridge to shortlist NST candidates and King's uses ESAT scores as a significant factor in interview decisions. Strong performance — particularly on the sections relevant to your intended specialisation — improves your chances meaningfully. Weak ESAT performance is difficult to overcome. Prepare for the ESAT seriously from October and treat it as integral to your Cambridge application.
Possibly. King's NST interviews often move between disciplines, and you may encounter questions from physics, chemistry, and biology in a single 30-minute session. The interdisciplinary nature of the first-year NST course means supervisors are specifically looking for students who can reason across subject boundaries. Prepare your weakest science subject as seriously as your strongest.
Giving descriptions rather than explanations. Supervisors consistently distinguish between candidates who can say what happens and candidates who can say why it happens at a mechanistic level. “Water moves by osmosis” is a description. “The difference in water potential creates a concentration gradient that drives net diffusion of water molecules across the membrane from the region of higher to lower water potential” is an explanation. Always push yourself to the level of mechanism.
Osmosis, then a pressure-volume sketch, then something you have not met
The questions above start inside A-level and then step outside it, which is the standard shape of a King's Natural Sciences interview. What is being assessed is the transition — whether the candidate keeps reasoning once the familiar ground runs out.
The satellite question worked through above is the same shape in miniature: a plausible first guess, tested by writing the algebra out in full rather than trusting the instinct, and a mass that only turns out to cancel once you actually do it.
Most Oxbridge interviews last between 20 and 45 minutes and are conducted by one or two subject tutors at the college you have applied to. The format focuses on academic discussion rather than personal statements — tutors typically give you an unseen problem, passage, or object and ask you to think through it aloud. They are assessing how you reason under pressure and engage with new ideas, not whether you arrive at a 'correct' answer. Preparation should therefore focus on practising structured reasoning and academic argument.
Only for the biology strand, and even then only partly. The Biological Sciences pack gives you ten worked questions with Hints behind each one and a full solution behind that, which is solid preparation for roughly a third of what a King's NST interview actually draws on, since the format spans physics, chemistry and biology together, not one science in isolation. What a printed pack cannot do is branch: every worked answer takes you down one fixed line of reasoning, while a live supervisor changes the follow-up depending on exactly what you said and how confidently you said it. Treat the pack as covering the biology third properly, with the physics and chemistry thirds still needing preparation of their own.