Understanding the Forces

* Weight (Force of Gravity): This is the 1000 N force pulling the barrel downwards.

* Drag Force: This is the 400 N force acting upwards, opposing the motion of the barrel due to air resistance.

Calculating Net Force

Net force is the overall force acting on an object. Since the forces are in opposite directions, we subtract them:

* Net Force = Weight - Drag Force

* Net Force = 1000 N - 400 N

* Net Force = 600 N

Conclusion

The net force on the barrel is 600 N downwards. This means the barrel is still accelerating downwards, but at a slower rate than if there were no air resistance.