Introduction to momentum | Impacts and linear momentum | Physics | Khan Academy

TL;DR

Momentum is the product of mass and velocity and is a measure of an object's motion.

Transcript

Welcome back. I will now introduce you to the concept of momentum. And the letter for momentum is, in physics, or at least in mechanics, it's the letter P. P for momentum. And I assume that's because the letter M has already been used for mass, which is I guess an even more fundamental idea. So P for momentum. So what is momentum? Well, you probabl... Read More

Key Insights

• 💆 Momentum is defined as mass times velocity.
• ⌛ Force is equal to the change in momentum per unit of time.
• 🪐 Momentum is conserved in a system without any net external forces.
• ⌛ Impulse is the product of force and time.
• 💆 The mass and velocity of an object determine its momentum.
• ❓ Momentum is a vector quantity, meaning it has both magnitude and direction.
• 👮 The law of conservation of momentum states that the total momentum of a system remains constant.

Questions & Answers

Q: What is the definition of momentum?

Momentum is equal to the product of an object's mass and velocity. It is a measure of how much motion an object has.

Q: How does force relate to momentum?

Force can be calculated as the change in momentum per unit of time. It is responsible for changing the momentum of an object.

Q: Is momentum conserved in a system without external forces?

Yes, momentum is conserved in a system without any net external forces acting on it. This means that the total momentum of the objects in the system remains constant.

Q: What is impulse?

Impulse is defined as the product of force and time. It can also be viewed as the change in momentum over a period of time. Impulse is measured in joules.

Summary & Key Takeaways

• Momentum is defined as the product of an object's mass and velocity.

• Force can also be viewed as the change in momentum per unit of time.

• Momentum is conserved unless there is a net force acting on the system.