Question

Using the free-body diagram, calculate the net force acting on the sled
newton. Is the sled in a state of dynamic equilibrium?

Answer 1

I don’t have the free‑body diagram or the numeric force values from your problem, so I can’t compute the exact net force yet. Please either attach the diagram or list each force (magnitude and direction).

Meanwhile, here’s exactly how to get the net force and decide about dynamic equilibrium:

Steps to compute the net force
1. Choose axes (usually x = horizontal along motion, y = vertical).
2. Resolve each force into components:
- If a force F is at angle θ above the +x axis: Fx = F cosθ, Fy = F sinθ.
- Take signs into account (left or down are negative).
3. Sum components:
- ΣFx = sum of all horizontal components
- ΣFy = sum of all vertical components
4. Resultant net force:
- Magnitude: Fnet = sqrt((ΣFx)^2 + (ΣFy)^2)
- Direction: θnet = arctan(ΣFy / ΣFx) (watch quadrant signs)
5. Units: result in newtons (N).

Dynamic equilibrium criterion
- If ΣFx = 0 and ΣFy = 0 (so Fnet = 0 N) the net force is zero. The sled is in equilibrium:
- If it’s moving at constant velocity, that’s dynamic equilibrium.
- If it’s at rest, that’s static equilibrium.
- If the net force is not zero, the sled is accelerating and is NOT in dynamic equilibrium.

Quick example
- Suppose forces: pull 100 N at 30° above horizontal to the right, friction 30 N to the left, weight 150 N down, normal 150 N up.
- ΣFx = 100 cos30° – 30 ≈ 86.6 – 30 = 56.6 N
- ΣFy = 100 sin30° + 150 (up) – 150 (down) = 50 N
- Fnet = sqrt(56.6^2 + 50^2) ≈ 75.6 N (direction ≈ 41.9° above horizontal)
- Since Fnet ≠ 0, the sled is not in dynamic equilibrium.

If you post the diagram or list of forces, I’ll compute the exact net force and state whether the sled is in dynamic equilibrium.