Introduction to Conservation of Momentum with Demonstrations

The video introduces the concept of momentum and its conservation in isolated systems. It explains how momentum is a vector quantity and is conserved during collisions and explosions. A demonstration using a skateboard and a medicine ball illustrates these principles. The video also discusses how rockets use momentum conservation for propulsion, comparing it to a hose's spray nozzle. The session concludes with a brief summary and closing remarks.

What is the condition for a system to be considered isolated in terms of forces?

• The net force on the system is equal to zero.

• The net force on the system is greater than zero.

• The system is at rest.

• The system is moving at a constant velocity.

In the demonstration with the skateboard and medicine ball, what is the initial momentum of the system?

• Undefined

• Positive

• Zero

• Negative

After the explosion in the demonstration, why does the person on the skateboard move to the right?

• Because the ball has positive momentum.

• Because the ball moves to the right.

• Because the ball has negative momentum.

• Because the skateboard is pushed by an external force.

How does the conservation of momentum explain the upward movement of a rocket?

• The rocket gains momentum by increasing its mass.

• The rocket gains momentum by ejecting fuel downward.

• The rocket gains momentum by reducing air resistance.

• The rocket gains momentum by pushing against the ground.

What happens to the spray nozzle when water is ejected downward?

• It remains stationary.

• It gains negative momentum.

• It loses mass.

• It gains positive momentum upward.