Grade 12 · Theory
Impulse and Newton's second law
Momentum and impulse · about 3 min
Visual overview: Impulse and Newton's second law1 MIN READ
2 study sections · pause after each one and recall the key ideaImpulse links force and time to the change in momentum an object experiences.
Key points- Impulse = FnetΔt = Δp = mvf − mvi.
- The same change in momentum over a LONGER time needs a smaller force.
- This is why airbags, crumple zones and padding reduce injury.
- Impulse is a vector with the direction of the net force.
- Impulse — force multiplied by contact time.
EXAM TIP
safety-feature questions always want the Δt ↑ therefore F ↓ argument, stated with the impulse equation.