Now that we know what momentum is, let's learn about the conservation of momentum and collisions.

Similar to the law of conservation of energy, this becomes a useful tool for studying and predicting the motion of objects. If we know the total momentum of a system of objects at any moment in time, we know that value will be the same at another moment in time.

The most common scenario where we apply the conservation of momentum is a collision. A collision is when 2 or more objects come into contact with each other, like 2 cars colliding. But we can also consider scenarios like explosions, where objects or pieces of an object start together and then fly apart. We'll learn about several types of events including elastic collisions, inelastic collisions, perfectly inelastic collisions and explosions.

Angular momentum is also conserved over time, just like linear momentum. Although they are very similar, it's important to establish that the law of conservation of angular momentum is separate because it actually provides its own predictions for the motion of objects.

Multiple-Choice Questions

Answers

Free-Response Questions

Momentum

• 2024 Q2 - - (Experimental design) Masses oscillating on a spring, simple harmonic motion, energy, momentum
• 2024 Q5 - - Collision of two blocks, momentum, energy, forces
• 2022 Q4 - - Clay and ball collide with blocks, momentum, projectile motion
• 2021 Q3 - - Student pushes disk which hits a block, momentum
• 2018 Q5 - - Block dropped on another oscillating block, energy, momentum, simple harmonic motion

Angular momentum

• 2023 Q4 - - Block hanging from string around pulley, rotational motion, torque, angular momentum, energy, work
• 2019 Q1 - - Plunger pushes block and sphere across surface, kinematics, forces, energy, work, torque, angular momentum
• 2017 Q3 - - Disk collides with pivoting rod, rotational motion, torque, angular momentum

• Professor Dave - Elastic and Inelastic Collisions
• Matt Anderson - Collisions in 2D
• Matt Anderson - Explosions
• Khan Academy - Deriving the shortcut for solving elastic collisions
• Khan Academy - How to use the shortcut for solving elastic collisions
• Integral Physics - Why is Energy Lost in Inelastic Collisions but Momentum is Conserved

• Michel van Biezen - Momentum in Space
• Michel van Biezen - Colliding with a Semi Truck
• Organic Chemistry Tutor - Conservation of Momentum
• Organic Chemistry Tutor - Elastic Collisions in One Dimension
• Organic Chemistry Tutor - Inelastic Collisions in One Dimension
• Organic Chemistry Tutor - Conservation of Momentum in Two Dimensions

• Walter Lewin - Momentum, Conservation of Momentum, Center of Mass

• Collision Lab
• Elastic and Inelastic Collisions
• Explosions

Other Resources

Now that we know what momentum is, let's learn about the conservation of momentum and collisions.

Similar to the law of conservation of energy, this becomes a useful tool for studying and predicting the motion of objects. If we know the total momentum of a system of objects at any moment in time, we know that value will be the same at another moment in time.

The most common scenario where we apply the conservation of momentum is a collision. A collision is when 2 or more objects come into contact with each other, like 2 cars colliding. But we can also consider scenarios like explosions, where objects or pieces of an object start together and then fly apart. We'll learn about several types of events including elastic collisions, inelastic collisions, perfectly inelastic collisions and explosions.

Angular momentum is also conserved over time, just like linear momentum. Although they are very similar, it's important to establish that the law of conservation of angular momentum is separate because it actually provides its own predictions for the motion of objects.