OxfordAQA IGCSE Physics: P3 Momentum and Safety

Master momentum, conservation of momentum, stopping distances and safety features for OxfordAQA IGCSE Physics 9203

Created byMuneeb Farooq

Last updated 4/2026

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What you'll learn

Calculate momentum using the equation p = mv and identify momentum as a vector quantity with correct units
Apply the law of conservation of momentum to solve collision and explosion problems with full working
Explain what happens during an explosion and calculate recoil velocity using conservation of momentum
Explain the difference between thinking distance, braking distance and total stopping distance clearly
Identify all factors that affect thinking distance and braking distance separately with correct explanations
Explain how safety features including airbags, seatbelts and crumple zones reduce injury using momentum principles
Use the equation F = change in momentum divided by time to explain why longer stopping time reduces force
Explain why a car travelling at steady speed requires a driving force to overcome friction and air resistance

Course content

1 section • 8 lectures • 31m total length

Welcome to P3 and What You Will Learn1:25
Explore momentum, the conservation of momentum, and the force equation, applying them to car crashes, explosions, rockets, and breaking distance with interactive simulators and practice problems.
What is Momentum and How to Calculate It2:08
Explore momentum as a property of objects, showing speed and mass affect momentum and why it is a vector. Learn formula p = m v and its units kg m/s.
Changes in Momentum and the Force Equation2:54
Conservation of Momentum and Collisions5:48
Explore momentum conservation in a closed system during a collision, equating initial and final momentum, and compute velocity using m1 u1 + m2 u2 = (m1 + m2) v.
Explosions and Recoil3:23
Investigate how explosions conserve momentum, with zero initial momentum and opposite-moving parts that cancel out. See cannon recoil and rocket eject gas, relating momentum to the F = ma relation.
Deceleration & Stopping Distances: Thinking and Braking9:55
Apply braking force to decelerate a vehicle and learn how thinking and braking distances combine into stopping distance, with safety features extending stopping time to reduce injury.
Factors Affecting Stopping Distance3:37
Examine thinking distance and braking distance, noting 0.7 s reaction time and 21 m at 70 mph, with factors like fatigue, distractions, alcohol or drugs, and road friction.
Safety Features and Steady Speed2:05

Requirements

It is helpful but not required to have completed P1 and P2 before starting this course. A basic calculator is needed for momentum and force calculations. No prior knowledge of momentum is needed as every concept is built from the beginning.

Description

This course covers P3 Momentum and Safety from the OxfordAQA IGCSE Physics specification 9203 in full. Every lecture is built directly around the specification so there is nothing missing and nothing unnecessary.

P3 is one of the most calculation-heavy topics in IGCSE Physics and one that students consistently find difficult. Momentum calculations, conservation of momentum, and stopping distance questions appear regularly on past papers. Mastering this topic early gives you a significant advantage in the exam.

In this course you will learn what momentum is and how to calculate it using the equation p = mv. You will understand the law of conservation of momentum and apply it to collisions and explosions, including the concept of recoil. Every calculation is broken down step by step so you know exactly what to write in the exam.

The course covers stopping distances in detail, explaining the difference between thinking distance, braking distance and total stopping distance. You will learn all the factors that affect each one and understand why braking distance is proportional to speed squared. You will also explore how safety features like airbags, seatbelts, crumple zones and helmets all work using the same principle of increasing the time taken to change momentum.

A practice quiz is linked in the resources section of each lecture on supermuneeeb so you can test yourself immediately after watching.

This course is taught by Muneeb Farooq, an IGCSE Physics, Chemistry and Mathematics specialist with 8 years of teaching experience across the UK, UAE, Bahrain and Pakistan.

Who this course is for:

Students studying OxfordAQA IGCSE Physics 9203 who need structured revision for P3 Momentum and Safety
IGCSE students who find momentum calculations and conservation of momentum difficult and want clear step-by-step explanations
Students preparing for past paper questions on stopping distances, safety features and momentum conservation