# How to find the coefficient of friction?

• trASHf
In summary, the conversation discusses a hypothetical scenario involving an object with a mass of 3.2kg, an applied force of 22.8N, and an acceleration of 3.02 m/s^2. The equations ma = FA + FfK and ma = FA -Mmg are used to represent the forces acting on the object, including the normal force, friction force, applied force, and gravitational force. The conversation also points out a mistake in the algebraic solution provided.
trASHf
Homework Statement
Unknown object has a mass of 3.2kg on steel plank.

|FA|=22.8N
|a|=3.02m/s^2

What is the material?
Relevant Equations
Newton's Second Law - sum of all forces = mass * acceleration = ...
GR (bold = mathematical convention)
m = 3.2kg
|applied force| = + 22.8 N
|acceleration| = + 3.02 m/s^2

FBD-hypothetical
^ normal force
|
friction force <-----*-----------> applied force
|
gravitational force

A
ma = FA + FfK
ma = FA -Mmg
ma/mg = FA - M
ma/mg - FA = -M

Hi,

Can you imagine it is hard to make sense of this ? Read what you posted

Last edited by a moderator:
BvU said:
Hi,

Can you imagine it is hard to make sense of this ? Read what you posted

other than the attempted solution I put there, no I don't think it's hard to make sense of this.

trASHf said:
ma = FA + FfK
ma = FA -Mmg
ma/mg = FA - M
ma/mg - FA = -M
Your algebra is faulty when you go from the second equation to the third. You need to divide all the terms on the right side by mg.

trASHf

## What is the coefficient of friction?

The coefficient of friction is a measure of how easily two surfaces slide against each other. It represents the amount of force needed to overcome the resistance between the two surfaces.

## How is the coefficient of friction calculated?

The coefficient of friction is calculated by dividing the force required to move an object over a surface by the weight of the object.

## What factors can affect the coefficient of friction?

The coefficient of friction can be affected by several factors, including the type of materials in contact, the roughness of the surfaces, and the presence of any lubricants.

## Why is the coefficient of friction important?

The coefficient of friction is important because it helps us understand the interactions between different surfaces and how much force is needed to move objects. It is also essential in designing machines and structures to ensure proper functionality.

## How can the coefficient of friction be measured?

The coefficient of friction can be measured using various methods, such as the inclined plane method, the block on block method, or the drag method. These methods involve measuring the force needed to move an object over a surface and calculating the coefficient of friction using the formula mentioned above.

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