# Finding Force by using the coefficient of friction and mass

• Alejandro Nava
In summary: I understand now.In summary, the man is pushing a 50 kg box up a 20-degree ramp at constant velocity. If the pushing force is parallel to the ramp, and the coefficient of friction is 0.4, how much force is he pushing with?The Attempt at a SolutionI tried to solve the problem but I ended up getting the frictional force instead of the force he is pushing with. Show us the details of what what you've tried so far.Make a free body diagram.Forces parallel to ramp mgsin(θ) and μFn. The man is pushing against weight component down the slope and friction.Forces parallel to ramp mgsin(
Alejandro Nava

## Homework Statement

A man pushes a 50 kg box up a 20-degree ramp at constant velocity. If the pushing force is parallel to the ramp, and the coefficient of friction is 0.4, how much force is he pushing with?

## Homework Equations

u=Fs, max/Fn Not sure if this equation is needed.

## The Attempt at a Solution

I tried to solve the problem but I ended up getting the frictional force instead of the force he is pushing with.

Show us the details of what what you've tried so far.

Make a free body diagram.

Forces parallel to ramp mgsin(θ) and μFn. The man is pushing against weight component down the slope and friction.

Last edited:
neilparker62 said:
Forces parallel to ramp mgsin(θ) and μFn.
Is that all?

Alejandro Nava said:

## The Attempt at a Solution

I tried to solve the problem but I ended up getting the frictional force instead of the force he is pushing with.

What you wrote here does not qualify as "attempt at a solution". You told us you couldn't do it (which is automatic when someone posts something in this subforum), but without seeing what you actually did, there is no way anyone can diagnose what you did wrong.

We are not allowed to give you outright solutions. We are, however, allowed to help you find the solution. And to do that, we need to know what you actually did. So show your work, especially your free-body diagram, as has been suggested.

Zz.

kuruman said:
Is that all?
Yes.

neilparker62 said:
Yes.

As mentioned in my post, the man is pushing against the above-mentioned forces and there will be zero resultant force since the block does not accelerate.

I agree that the resultant force is zero. I disagree about the number of forces acting on the block. I can count 3 in the direction parallel to the incline that should add to zero: pushing force by man, friction by incline, component of gravity. How many are there according to your count?

Quite right - there are 3 forces in equilibrium so the OP will need to add two of them to obtain the third. Or alternatively add all 3 and set equal to zero with the pushing force being the unknown.

neilparker62 said:
Quite right - there are 3 forces in equilibrium so the OP will need to add two of them to obtain the third. Or alternatively add all 3 and set equal to zero with the pushing force being the unknown.
You got it!

kuruman said:
You got it!
More importantly I hope the OP did too!

Thank you all for trying but I ended up going to the teacher to ask how to do the problem and I understand how to do the question. What I did wrong was that when I was trying to find the force, I used COH instead of TOA. Sorry for the inconvenience.

gneill said:
Show us the details of what what you've tried so far.
Perhaps this was the correct response to the OP's query! I'm not sure what either COH nor TOA mean.

## 1. What is the coefficient of friction?

The coefficient of friction is a measure of the amount of resistance between two surfaces in contact. It is a unitless value that ranges from 0 to 1, with 0 indicating no friction and 1 indicating high friction.

## 2. How is the coefficient of friction related to force?

The coefficient of friction is directly related to the force required to move an object across a surface. A higher coefficient of friction means a greater force is needed to overcome the resistance between two surfaces.

## 3. How is mass involved in finding force using the coefficient of friction?

Mass is a factor in calculating force using the coefficient of friction. The greater the mass of an object, the more force is needed to move it across a surface with a given coefficient of friction.

## 4. What is the formula for calculating force using the coefficient of friction and mass?

The formula is force = coefficient of friction x mass x acceleration due to gravity (F = μmg). This formula takes into account the resistance between two surfaces, the mass of an object, and the force of gravity acting on the object.

## 5. How can the coefficient of friction be used in real-world applications?

The coefficient of friction is used in many fields, such as engineering and physics, to design and analyze the movement of objects. It is also used in everyday situations, such as determining the force needed to push or pull an object, or selecting the appropriate materials for different surfaces to reduce friction and improve efficiency.

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