Finding the coefficient of friction (mew) DUE TOMOROW

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To find the coefficient of friction (mew) for the curling stone, the force of friction must be determined using the formula F_friction = mew * Fn, where Fn is the normal force calculated as 196.2 N. The data collected includes times and distances for trials both with and without sweeping, which are essential for calculating average coefficients of friction. To find the force of friction, one approach is to assume linear deceleration due to friction, using the final speed, time, and distance to calculate deceleration. This can be done using kinematic equations, which will ultimately allow for the calculation of mew. Accurate calculations based on the provided data will yield the required coefficients of friction.
newton2008
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Finding the coefficient of friction (mew) DUE TOMOROW :(

Our physics class went curling, and this is the data we had to collect..

Without Sweeping

Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7
Time (s) 21.37 21.70 21.65 21.95 20.47 20.69 22.30
Distance (m) 115.50 145.50 125.50 112.00 28.00 28.50 261.50

With Sweeping

Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7
Time (s) 22.06 20.75 24.31 21.50 22.13 21.87 18.15
Distance (m) 147.00 75.50 320.00 18.00 255.00 198.00 42.00

Distances are measured past the second hog line, add 868 inches, and convert to metres.

Mass of Stone = 20 kg (2 sig. digs)
1 ft. = 0.3048 m

One of the question asks to: Calculate the average coefficients of friction with and without sweeping.

So I calculated the Fn = (20)(9.81) = 196.2 N

But the Force of Friction = (mew) * (Fn)

How am i supposed to find the force of friction? So then i can find the (mew)

someone pleaseeeee help
 
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i suppose you could assume the decceleration due to friction was linear in time so, knowing the final speed, time and distance, you could calculate the decceleration and hence the force using the "vusat" equations
 

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