p = mv — "Pretend Mass is Velocity's bodyguard": Momentum (p) is calculated when mass (m) and velocity (v) work together. The unit kg m/s reminds you it includes both kg (mass) and m/s (velocity).
Conservation — "The Ledger Rule": Think of momentum like money in a ledger. It can be transferred between objects (like transferring money between accounts) but the TOTAL amount never changes — it's always balanced.
Direction tip: Pick one direction as positive (e.g., right = positive, left = negative). An object moving left has negative momentum. Stick to your chosen convention throughout the whole problem!
This memory aid covers Memory Aid within Momentum for GCSE Physics. Revise Momentum in Forces for GCSE Physics with 15 exam-style questions and 6 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 8 of 12 in this topic. Use it for quick recall, then test yourself straight afterwards so the memory aid becomes usable in an answer.
Practice questions for Momentum
What is the equation for momentum?
Explain what is meant by saying momentum is a vector quantity.