NSAA Practice Test

The NSAA was the science admissions assessment used for Cambridge Natural Sciences, and the ESAT has replaced it. This page gives applicants free practice sets in biology, chemistry, mathematics and physics, three worked questions with full explanations, a study plan, and a short summary of the current test facts.

NSAA Exam at a Glance

What changed for NSAA in 2026

• Oct 28, 2026: Booking for the January 2027 ESAT sitting is expected to open on 28 October 2026. This is later than the 26 October date recorded earlier.^[4]
• Oct 24, 2026: Eligibility (ESAT (replaced NSAA)) changed to Required for Cambridge Natural Sciences; Cambridge applicants sit in October (previously Required for Cambridge Natural Sciences; Cambridge applicants generally sit in October).^[3]
• Oct 24, 2026: Passing score (ESAT (replaced NSAA)) changed to No pass mark; each module scored 1–9 (previously No pass/fail; each module scored 1.0–9.0).^[1]
• Oct 24, 2026: Registration opens (ESAT (replaced NSAA)) changed to January 2027 booking expected to open 28 October 2026, 3pm GMT (previously January 2027 booking opens 26 October 2026, 3pm).^[1]
• Oct 24, 2026: Late registration deadline (ESAT (replaced NSAA)) changed to No bookings accepted after the deadline (previously No late bookings accepted).^[4]

What the NSAA is and how it works

According to Admissions Testing Service / UAT-UK (ESAT, which replaced the NSAA), delivered by Pearson VUE, “Each module lasts 40 minutes and contains 27 multiple choice questions.”^[1]

The NSAA has been replaced by the ESAT, which is run by Admissions Testing Service (UAT-UK). Our practice sets keep the NSAA names, and they are useful for building science and maths fluency. The sets are written by us and are not real exam questions.

The ESAT is computer-based and is delivered by Pearson at test centres worldwide. Cambridge requires it for Natural Sciences, and Cambridge applicants sit in October. The test lasts 120 minutes for most candidates and is split into 40-minute modules. Each module has 27 multiple-choice questions, which makes 81 for 3 modules.

There is no pass mark. Each module is reported on a scale from 1 (low) to 9 (high) to one decimal place. Results arrive approximately 4 weeks after your sitting.

You may sit each test only once per admissions cycle. For the January sitting, the test window is 4 to 8 January 2027. Booking is expected to open on 28 October 2026 at 3pm GMT, and the deadline is 21 December 2026 at 6pm GMT. UAT-UK cannot accept bookings after the deadline. Which sitting and which modules apply to you depends on your course and university, so check the official ESAT pages and your university's admissions page before you book.

Worked examples: how to reason through NSAA questions

These are practice questions written for this site, not questions from the real exam. Each explanation shows why the right answer is right and why the others are wrong.

Example 1

Question: What is the pH of a 0.01 M solution of HCl?

1. 2
2. 1
3. 3
4. 4

Answer: A. 2

Explanation:

The correct answer is 2. HCl is a strong acid, so it dissociates completely and the hydrogen ion concentration equals the acid concentration, 0.01 M. Then pH = -log[H⁺], and the logarithm of 0.01 is -2, so the pH is 2.

The answer 1 would need a much more concentrated acid. The answer 3 or 4 would suggest a weaker acid or a more dilute solution, which would only apply if the acid did not fully dissociate or had been diluted further. The question gives neither.

Rule to remember: for a strong monoprotic acid, concentration of H⁺ equals concentration of acid, and each tenfold dilution raises the pH by a single unit.

Example 2

Question: Which type of bond is formed between the oxygen and hydrogen atoms within a single water molecule?

1. Covalent bond
2. Ionic bond
3. Hydrogen bond
4. Metallic bond

Answer: A. Covalent bond

Explanation:

The correct answer is a covalent bond. Oxygen and hydrogen are both non-metals, and inside the molecule they share electrons, which is what a covalent bond is.

An ionic bond is wrong because that needs electrons to transfer fully from a metal to a non-metal, which does not happen here. A hydrogen bond is wrong because it is a weaker attraction between separate water molecules, not the bond inside a molecule. A metallic bond is wrong because it describes a lattice of metal atoms sharing a sea of delocalised electrons.

Rule to remember: ask whether the bond is within a molecule or between molecules, then check whether the atoms are metals or non-metals. Sharing points to covalent, and transfer points to ionic.

Example 3

Question: A 5 kg block slides down a frictionless incline of 30°. What is its acceleration?

1. 4.9 m/s²
2. 8.5 m/s²
3. 9.8 m/s²
4. 2.5 m/s²

Answer: A. 4.9 m/s²

Explanation:

The correct answer is 4.9 m/s². On a frictionless incline only the component of gravity along the slope accelerates the block, so a = g sin30°. With g as 9.8 m/s², that gives 4.9 m/s².

The answer 9.8 m/s² is wrong because it is free-fall acceleration, which would only apply for a vertical drop. The answer 8.5 m/s² is wrong because it matches the component perpendicular to the slope, which uses cosine and is balanced by the normal force. The answer 2.5 m/s² does not follow from either component.

The 5 kg mass is a distraction, because it cancels: force and mass both scale together. Rule to remember: on a frictionless slope, acceleration is g times the sine of the angle, and it does not depend on mass.

How to use these practice tests

Start by reading the official ESAT pages so you know the format: 40-minute modules, 27 multiple-choice questions in each, and no pass mark. Then check which modules your course needs. Your target is a steady score on those modules, not a single number to hit.

1. Work through the practice sets for your subjects, for example Mathematics - Algebra and Functions, Physics - Mechanics, Chemistry and Biology. Do a short set untimed first and read every explanation, including those for answers you got right.
2. Keep a log of mistakes. Label each one as a knowledge gap, a calculation slip or a misread question, and revisit the log each week.
3. Add time pressure gradually. Once accuracy is steady, work through questions at the pace of a 40-minute module, and practise skipping a hard question and returning to it.
4. Return to weak topics, such as Calculus or Electricity and Magnetism, using the official specification as your checklist.
5. Close to your sitting, do the official sample material under test conditions, since it reflects the real format better than any third-party set.

Sources & last verified

1. Admissions Testing Service / UAT-UK (ESAT, which replaced the NSAA), delivered by Pearson VUE — number of questions, time limit, passing score, score release (official source). “Each module lasts 40 minutes and contains 27 multiple choice questions.” Verified Oct 27, 2026 · source checked Oct 27, 2026.
2. pearsonvue.com — retake policy, delivery (official source). “You are only permitted to sit each test once per admissions cycle.” Verified Oct 27, 2026 · source checked Oct 27, 2026.
3. undergraduate.study.cam.ac.uk — eligibility (official source). “You need to take the Engineering and Science Admissions Test (ESAT) if you are applying for:” Verified Oct 24, 2026.
4. Admissions Testing Service / UAT-UK (ESAT, which replaced the NSAA), delivered by Pearson VUE — registration deadline, other, late registration deadline (official source). “21st December 2026 6pm GMT” Verified Oct 27, 2026 · source checked Oct 27, 2026.

How we verify: editorial & fact-checking policy. Report an error: contact us.