What is the coefficient of friction between surface and the mass?

AI Thread Summary
To find the coefficient of friction between a 50 kg mass and a horizontal surface, a horizontal force of 4.08x10^6 dynes is applied. The equation used is Ff = u * mg, where Ff is the frictional force, u is the coefficient of friction, m is mass, and g is acceleration due to gravity. The initial calculation attempts to convert dynes to Newtons, which is necessary for consistency in units. The correct approach involves using the conversion factor for dynes to Newtons and ensuring mass is in kilograms. The discussion emphasizes understanding unit conversions and the correct application of the friction formula to find the coefficient of friction.
yss83
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Homework Statement


A mass of 50 kg is kept in uniform motion along a horizontal surface by a horizontal force of 4.08x10^6 dynes. What is the coefficient of friction between surface and the mass?


Homework Equations


(I searched previous answered questions and found this)
Ff= u * mg


The Attempt at a Solution


Our teacher hasn't actually started with our friction topic yet, but she always makes us do these assignments beforehand so we come "prepared" to her lectures. But I have no idea how to start. So I tried this, but I think it's incorrect.

4.08 x 10 ^ 6 dyn / (50 kg * 9.8 m/s^2) = 8326.531

Coefficients aren't supposed to be that big, right? So I tried converting. This is really embarrassing, but I'm not familiar with dyn so I had to look for its conversion factor to meters.

40.8 m / (50000 g * 9.8 m/s^2) = 8.32 x 10 ^-5

Even just clearing out the dyn thing would be great. I mean, if the values I used are correct? :) Thanks.
 
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Hi yss83, welcome to PF.
Convert dyne to Newton.
Keep mass in kg, and g in m/s^2.
Now find u.
 

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