Understanding Isolated Systems and Momentum

What is the primary reason for defining which objects are in a system?

• To identify the color of the objects

• To determine the mass of the objects

• To calculate the speed of the objects

• To define internal and external interactions

Which of the following is an example of a non-isolated system?

• An object in freefall

• A pendulum in a vacuum

• A block on a smooth surface

• Two objects in space with no external forces

According to Newton's third law, what happens when two objects exert forces on each other?

• The forces do not affect each other

• The forces are equal and opposite

• The forces cancel out completely

• The forces are unequal and in the same direction

In an isolated system, what is the net force acting on the system?

• It is equal to the gravitational force

• It is equal to the sum of all internal forces

• It is equal to the sum of all external forces

• It is zero

What does the conservation of momentum imply for an isolated system?

• The final momentum is greater than the initial momentum

• The initial momentum is equal to the final momentum

• The initial momentum is greater than the final momentum

• The total momentum changes over time