Solving for distance using only initial velocity and coefficient of friction

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Homework Help Overview

The problem involves determining the distance a box will slide across a surface after being given an initial velocity, considering the coefficient of friction. The initial speed is provided, along with the coefficient of friction, while the mass of the box is not specified, raising questions about how to approach the problem without complete information.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss using conservation of energy and the relationship between kinetic energy and friction. Some express uncertainty about whether there is sufficient data to solve the problem, while others suggest that mass may not be necessary for the calculations.

Discussion Status

The discussion is ongoing, with various participants exploring different interpretations and approaches to the problem. Some have offered guidance related to energy concepts, while others question the adequacy of the provided information. There is no explicit consensus on the best method to proceed.

Contextual Notes

Participants note that the problem may be situated within early physics education, where certain concepts like work and energy may not yet be introduced. Additionally, some participants relate their own similar questions, indicating a broader context of inquiry around the topic.

manuela4
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This problem is quite difficult for me. I know that there's a way to do this, but i can't figure it out. Could someone point me in the right direction? i don't need a solution, but a process would be nice.

Homework Statement


A box is given an initial push so that it slides across the floor. How far will it go, given that the coefficient of friction is 0.30 and the push imparts an initial speed of 3.0 m/s?

so Vi = 3.0 m/s, Vf= 0 m/s and Mu = .3
gravity is always active (at 9.81 m/s2), but i have no mass to calculate its force.

Homework Equations


all i know for friction:
F=ma (but i don't have mass, acceleration)
F= Mu Fn (Mu being the coefficient of friction, Fn being normal force)
i havnt chosen a distance equation because i don't have enough variables to do so.


The Attempt at a Solution


Without a formula, i can't solve... i can't even get started.
 
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Use conservation of energy. You start with kinetic energy it goes into friction (ie heat).
Energy is force * distance, where the force is the frictional force slowing it down.
 
You sure the question states only that? Cause I strongly think that there's not enough data to solve this problem.
 
The mass cancels.
KE = 1/2 mv^2
Friction = distance*mgu
 
mgb's prefectly right. apologies for not recognising that :)
 
Actually, althought relating the Kinetic Energy equation to the equation about friction and distance might be conceptually valid, it isn't the clue this person needed.

At the early point (probably around chapter 4) of an "elementary physics" textbook, a student encounters problems where, given an initial velocity and coefficient of friction , the student is expected to provide the resulting final displacement. This is a stage of the textbook where kinetic energy equations and "work" equations have not yet been introduced, therefore there is a different solution.

Since this person made their inquiry in November of 2008, I'm sure they're not waiting for the answer anymore, but I will return with an answer tomorrow.
 
I have the same problem, except that initial velocity is 2m/s
I know this is a bump, but it is the closest I can get to my question
 
I have a similar question yet in reverse.

Given:
Final displacement = 12m
Coefficient of Friction = .28

Find:
Initial velocity = 0

I am assuming to look for an equation that cancels masses out, yet need help with the next step
 
NVM I found a working formula.

1/2mv^2=displacement*mgu

so the masses cancel leaving

1/2v^2=Δxgu (horizontal direction)

Thanks for everyone else posting questions!
 

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