The illustrations depict four objects subject to various forces. The arrows indicate the direction of the forces, and the forces are measured in newtons (N). According to Newton's law of inertia, which object is maintaining a constant speed, assuming all four objects are on a frictionless surface?(1 point)

Responses

There is a box with Object 2 labeled inside. To the left of the box that are two arrows pointing left. The first arrow is labeled 1 N and the second arrow is labeled 12 N. There are also two arrows on the right side of the box that are pointing right. The first arrow is labeled 2 N and the second arrow is labeled 6 N.
Image with alt text: There is a box with Object 2 labeled inside. To the left of the box that are two arrows pointing left. The first arrow is labeled 1 N and the second arrow is labeled 12 N. There are also two arrows on the right side of the box that are pointing right. The first arrow is labeled 2 N and the second arrow is labeled 6 N.

There is a box with Object 3 labeled inside. There is one arrow on the left side of the box that is pointing left and labeled 5 N. There is one arrow on the right side of the box that is pointing right and labeled 8 N.
Image with alt text: There is a box with Object 3 labeled inside. There is one arrow on the left side of the box that is pointing left and labeled 5 N. There is one arrow on the right side of the box that is pointing right and labeled 8 N.

There is a box with Object 4 labeled inside. On the left side of the box there are two arrows pointing left. The first arrow is labeled 4 N and the second arrow is labeled 2 N. There is one arrow on the right side of the box that is pointing right and labeled 6 N.
Image with alt text: There is a box with Object 4 labeled inside. On the left side of the box there are two arrows pointing left. The first arrow is labeled 4 N and the second arrow is labeled 2 N. There is one arrow on the right side of the box that is pointing right and labeled 6 N.

There is a box with Object 1 inside it. There is an arrow on the left side of the box pointing left and labeled 5 N. There are two arrows on the right side of the box that are pointing right and they are each labeled 5 N.

1 answer

To determine which object is maintaining a constant speed according to Newton's law of inertia, we need to analyze the net forces acting on each object.

Newton's first law states that an object at rest stays at rest, and an object in motion continues to move at a constant speed in a straight line unless acted upon by a net external force.

Let's calculate the net forces for each object:

  1. Object 1:

    • Left: 5 N (left)
    • Right: 5 N + 5 N = 10 N (right)
    • Net force = \(10 N - 5 N = 5 N\) (right)
    • Not constant speed (there is a net force).
  2. Object 2:

    • Left: 1 N + 12 N = 13 N (left)
    • Right: 2 N + 6 N = 8 N (right)
    • Net force = \(8 N - 13 N = -5 N\) (left)
    • Not constant speed (there is a net force).
  3. Object 3:

    • Left: 5 N (left)
    • Right: 8 N (right)
    • Net force = \(8 N - 5 N = 3 N\) (right)
    • Not constant speed (there is a net force).
  4. Object 4:

    • Left: 4 N + 2 N = 6 N (left)
    • Right: 6 N (right)
    • Net force = \(6 N - 6 N = 0 N\)
    • It is maintaining constant speed (no net force).

Therefore, Object 4 is maintaining a constant speed, as there is no net force acting on it.