What is the change in eastward momentum of a disk that rebounds after striking a post?

What is the change in eastward momentum of a disk that rebounds after striking a post?

• A. -4 kg m/s
• B. -1 kg m/s
• C. 0 kg m/s
• D. 4 kg m/s

Answer: (A)

To determine the change in eastward momentum of the disk after it strikes a post and rebounds, we need to consider the principles of momentum and how it changes with direction. Momentum is defined as the product of mass and velocity. When the disk moves eastward and strikes the post, its momentum in the eastward direction is positive. Upon rebounding, if the disk travels in the opposite direction (westward), its momentum will then be negative. The change in momentum is calculated by subtracting the initial momentum from the final momentum. If the disk initially has an eastward momentum of, for example, +4 kg m/s and then rebounds westward with a momentum of -0 kg m/s (indicating no eastward motion), the total change in momentum would be: Final momentum (westward, negative) - Initial momentum (eastward, positive) = -0 kg m/s - (+4 kg m/s) = -4 kg m/s. This indicates that there has been a total change of -4 kg m/s in the eastward momentum, meaning that the disk has effectively reversed its directional momentum after colliding with the post. This analysis confirms that the correct answer accurately reflects the change in eastward momentum due to the direction

To determine the change in eastward momentum of the disk after it strikes a post and rebounds, we need to consider the principles of momentum and how it changes with direction.

Momentum is defined as the product of mass and velocity. When the disk moves eastward and strikes the post, its momentum in the eastward direction is positive. Upon rebounding, if the disk travels in the opposite direction (westward), its momentum will then be negative.

The change in momentum is calculated by subtracting the initial momentum from the final momentum. If the disk initially has an eastward momentum of, for example, +4 kg m/s and then rebounds westward with a momentum of -0 kg m/s (indicating no eastward motion), the total change in momentum would be:

Final momentum (westward, negative) - Initial momentum (eastward, positive) = -0 kg m/s - (+4 kg m/s) = -4 kg m/s.

This indicates that there has been a total change of -4 kg m/s in the eastward momentum, meaning that the disk has effectively reversed its directional momentum after colliding with the post.

This analysis confirms that the correct answer accurately reflects the change in eastward momentum due to the direction