Cambridge IGCSE Physics Notes 1.6: Momentum
Cambridge IGCSE Physics momentum notes on momentum, impulse, force-time relationships, conservation, collisions, and safety applications.
Q: What does Cambridge IGCSE Physics Notes 1.6: Momentum cover?
A: It follows official Cambridge Physics section 1.6 for syllabuses 0625 and 0972, with Core ideas separated from Supplement depth.
Momentum combines mass and velocity. In an isolated system total momentum is conserved, while force changes momentum over time.
The ideas that organise this section
- Momentum is a vector, so direction signs matter.
- Conservation applies to the total system when external resultant force is negligible.
- Increasing collision time reduces average force for the same momentum change.
Core route
Core candidates should be ready to describe, calculate, interpret, and apply the following:
- Calculate momentum and describe safety features that increase stopping time.
- Relate force to a change in momentum qualitatively.
- Apply conservation to straightforward one-dimensional interactions.
Supplement route
Extended candidates study all Core content and add the following depth:
- Use impulse and force-time relationships quantitatively.
- Solve collision and recoil problems with a consistent positive direction.
- Connect the area under a force-time graph to impulse when presented with data.
Formula route
- Relationship: momentum = mass x velocity.
- Relationship: impulse = force x time = change in momentum.
Write the relationship before substituting. Convert units first, keep extra figures during working, and round only the final answer to sensible precision.
Build a connected model
In Momentum, a strong answer connects the named quantity or model to observable evidence. Begin by defining the physical quantity in words or with its relationship. Identify which values are scalars and which require a direction. Represent the situation with a labelled diagram, graph, field pattern, ray or circuit when that makes the relationship visible. The representation is part of the reasoning: its labels, arrows and scale should agree with the written explanation.
For a calculation, write the governing relationship before substitution, convert prefixes and time units, keep unrounded values during working and attach the correct final unit. For a qualitative question, use a cause-link-consequence chain. Name what changes, state the physical mechanism that links the change to the system, and then give the measurable result. If two cases are compared, hold unrelated variables constant and use the same physical principle for both.
