Is the Normal Force Larger in a Box-Pushing Scenario?

Therefore, the statement "The normal force is larger than the weight of the box" is true. In summary, the normal force is greater than the weight of the box because it must counteract both the downward component of the applied force and the gravitational force. This is in accordance with Newton's First Law and the equations provided in the post.
  • #1
hydride
2
0

Homework Statement



A box is being pushed across the floor with a 250 N force directed 20ο
below the horizontal. Is The normal force is larger than the weight of the box?

True or False.

Explain.

Homework Equations



sin(20) = opp/hyp

The Attempt at a Solution



Fn = 250sin(20o) + Fg

Please help explain how this problem is done, and why we would add Fg. Thank you.
 
Last edited:
Physics news on Phys.org
  • #2
The force is being applied at an angle below the horizontal. Therefore, the normal force must counteract both the downward component of the applied force and the gravitational force.
 
  • #3
But how do we know if it is greater than the weight of the object? Shouldn't it be equal?
 
  • #4
the normal force is the perpendicular contact force of the floor acting on the box. It's value must be in accord with Newton's 1st law, per Precursor's response, and the equations you noted above in your initial post.
 
  • #5
The normal force is greater than the weight because it has to balance both gravitational and applied force.
 

1. Is the Normal Force always equal to the weight of an object?

No, the Normal Force is not always equal to the weight of an object. The Normal Force is a reaction force that is equal in magnitude and opposite in direction to the force applied by the object on a surface. The weight of an object is a downward force due to gravity, while the Normal Force is a perpendicular force exerted by a surface on an object. These two forces may be equal in some situations, but not always.

2. How does the Normal Force change with the angle of inclination?

The Normal Force is affected by the angle of inclination, or the slope, of the surface on which an object rests. As the angle of inclination increases, the Normal Force also increases, since the surface is now exerting a greater perpendicular force to counteract the component of the object's weight that is acting parallel to the surface.

3. Can the Normal Force be negative?

No, the Normal Force cannot be negative. Since the Normal Force is a reaction force, it always acts in the direction perpendicular to the surface. It may decrease or increase in magnitude, but it cannot be negative. A negative value for the Normal Force would imply that the surface is exerting a force in the opposite direction of the object, which is not possible.

4. How does the Normal Force affect the motion of an object?

The Normal Force does not directly affect the motion of an object. It is a reaction force that helps to keep an object in contact with a surface and prevents it from falling through or slipping on the surface. The Normal Force does not contribute to the net force acting on an object, but it plays a crucial role in ensuring the object's stability and equilibrium.

5. Can the Normal Force be greater than the weight of an object?

Yes, the Normal Force can be greater than the weight of an object. This can occur in situations where an additional external force is acting on the object, such as when an object is pushed down onto a surface. In this case, the Normal Force would be greater than the weight of the object, as it is now counteracting not only the weight of the object but also the additional force pushing it down.

Similar threads

  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
6
Views
3K
  • Introductory Physics Homework Help
Replies
9
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
8K
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
893
Back
Top