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Normal Force Card Sort - Questions 4 Help

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A scale will read a force value that is equal to the normal force exerted by the scale upon the object that is in contact with its top surface. By analyzing all the other forces that act upon that object, it is possible to predict a value for the scale reading.

Here is ...

Question 4
Consider the following situation and categorize it according to the relative strength of the normal force (or scale reading). Category options include:

  1. The normal force is equal to the weight of the object.
  2. The normal force is greater than (>) the weight of the object.
  3. The normal force is less than (<) the weight of the object.
  4. There is not enough information to decide.

The 5.0-kg box is above the scale and not touching it. Normal forces exist when two in-contact objects have their surfaces pressed together. For instance, if you sit on a chair cushion, gravity pulls you downwards and your body and the chair cushion are pressed together. This pressing together of the two surfaces causes the normal force. But if there is no contact then there is no pressing together of the surfaces. The result is that there is no normal force.

This is the type of thinking you need to apply to this question. Now go answer it with confidence.

You can learn more about force types and force diagrams by using the following links to The Physics Classroom's Tutorial section.

Types of Forces

Drawing Free Body Diagrams