Coefficient of Friction/Projectile motion problem

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A block is projected at 3.0 m/s on a horizontal surface and comes to rest after traveling 1.5 m, prompting a calculation of the coefficient of kinetic friction. The main challenge is the absence of the block's mass, leading to confusion about how to determine the normal force. Participants suggest treating the mass as a variable 'm' to simplify calculations. The normal force can be expressed symbolically as mg, allowing for further analysis of the forces acting on the block. The discussion emphasizes the importance of understanding the relationship between friction, mass, and motion in solving the problem.
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Homework Statement



A block is projected with a speed of 3.0 m/s on a horizontal surface. if the block comes to rest in 1.5 m, what is the coefficient of kinetic friction between the block and the surface?

Homework Equations



M=Ff/N
(Fapplied-Ff)=ma

I'm not really sure which equations to use for this problem since there is no mass given for the block.


The Attempt at a Solution



I really have no idea how to go about doing this problem!

I've been solving more complex friction problems but I'm currently baffled since there is no way to calculate a force, etc.
I'm taking a 12th grade physics class, by the way.
 
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rmiller94 said:
I'm not really sure which equations to use for this problem since there is no mass given for the block.
Maybe it doesn't matter. :wink: Just call the mass 'm' and continue. What's the force acting on the block?
 
i'm not really sure since there's no mass or weight given it seems impossible to find the normal force.

the only givens are in the problem stated above.

i'm so confused! hahah
 
rmiller94 said:
i'm not really sure since there's no mass or weight given it seems impossible to find the normal force.
Call the mass 'm'. What's the normal force? (Give it symbolically, not in terms of numbers.)
 
ooh haha i guess the normal force would just be mg?
 
rmiller94 said:
ooh haha i guess the normal force would just be mg?
Right! Keep going.
 

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