Question 1

What is the difference between elastic and inelastic collisions?

Accepted Answer

In an elastic collision, both momentum and kinetic energy are conserved. In a perfectly inelastic collision, momentum is conserved but kinetic energy is not — the objects stick together after impact.

Question 2

What is impulse?

Accepted Answer

Impulse (J) is the change in momentum of an object, equal to the force applied multiplied by the time interval: J = F·Δt. It equals the change in momentum: J = Δp.

Question 3

Is momentum always conserved in a collision?

Accepted Answer

Yes. In a closed system with no external forces, total momentum is always conserved in both elastic and inelastic collisions.

Momentum and Collision Calculator

Momentum (p = mv)

Impulse (J = F·Δt)