# Normal Force negligible?

• rygza

#### rygza

My instructor told the class to keep in mind that we should only account for normal force when friction is involved in the problem. In my book there is a problem in which friction is negligible and they account for normal force, but ultimately the normal force has no effect on the conclusion of the problem.

Should I not include normal force in my diagrams if there is no friction?

hi rygza!

if the problem is about things moving on a plane (horizontal or sloping), then (if there's no friction) there's no movement, and therefore no acceleration, perpendicular to the plane, and so the perpendicular forces are irrelevant (ie your instructor is correct)

but if the surface is curved, then even though there's no movement perpendicular to the plane, there is a centripetal acceleration perpendicular to it, and so any perpendicular forces (including the normal forces) are relevant
rygza said:
Should I not include normal force in my diagrams if there is no friction?

If you're only interested in forces and acceleration along the surface, there's no need to clutter the diagram with perpendicular forces

## 1. What is normal force negligible?

Normal force negligible refers to a situation where the force exerted by an object on another object is so small that it can be disregarded in calculations or analysis. This is usually the case when the two objects are not in direct contact or the force is significantly smaller than other forces acting on the object.

## 2. How is normal force negligible calculated?

In most cases, normal force negligible is determined by comparing it to other forces acting on an object. If the normal force is significantly smaller than other forces, it can be considered negligible. However, in some cases, a more precise calculation may be necessary using equations such as F=ma (force equals mass times acceleration) or F=μN (force of friction equals coefficient of friction times normal force).

## 3. What are some examples of normal force negligible?

One common example of normal force negligible is a book resting on a table. The weight of the book exerts a force on the table, but the normal force exerted by the table on the book is negligible compared to other forces such as gravity and air resistance. Another example is a car moving on a flat road, where the normal force exerted by the road on the tires is negligible compared to the force of the engine propelling the car forward.

## 4. Why is normal force negligible important in science?

Normal force negligible is important in science as it allows us to simplify calculations and focus on the most significant forces acting on an object. By disregarding insignificant forces, we can better understand the behavior and motion of objects. It also helps in making accurate predictions and designing experiments.

## 5. Can normal force negligible ever be ignored completely?

In most cases, normal force negligible can be ignored without significant consequences. However, there may be situations where a more precise calculation is necessary, and even a small amount of normal force may have an impact. Therefore, it is important to carefully consider all forces acting on an object and use appropriate equations and calculations when necessary.