Question

The force pulling a truck downhill is 2,000 N. What is the amount of static friction acting on the truck if the truck does not move?

Answer 1

So, amount of static friction acting on the truck if the truck does not move is 2,000 N.

Introduction

Hi ! Here I will help you to solve the problem about static friction. Friction is a force that inhibits or reduces the value of the force acting on an object. If viewed from the direction of the initial force, the frictional force will always have a negative value (-) due to always have opposite direction from the intial direction. Friction is divided into two types, namely :

• Static friction (
  `\sf{f_s}`), occurs when the resultant force is 0 N or in other words the object is still at rest.
• Kinetic friction (
  `\sf{f_k}`), occurs when the object has moved, so that the resultant force not 0 N.

Formula Used

The formula used in this case is the equation for static friction. Pay attention at below.

`\sf{\sum F = 0}`

`\sf{F - f_s = 0}`

`\boxed{\sf{\bold{F = f_s}}}`

With the following condition :

• 
  `\sf{\sum F}` = resultant of the force (N)
• F = force that applied to object (N)
• 
  `\sf{f_s}` = static friction (N)

Solution

We know that :

• The truck affected by static friction
• F = force that applied to object = 2,000 N

What was asked ?

• 
  `\sf{f_s}` = static friction = ... N

Step by step :

`\sf{\sum F = 0}`

`\sf{F - f_s = 0}`

`\sf{F = f_s}`

`\boxed{\sf{2,000 \: N= f_s}}`

Conclusion

So, amount of static friction acting on the truck if the truck does not move is 2,000 N.