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HappyScientist
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This is not exactly a homework question, but rather a question I pose to a set of experiments I preformed as an extension after my original assignment. I would like to know the answer to this question as I have been asked to demonstrate to my fellow classmates the experiment.
An experiment was conducted to find the coefficient of friction on rubber, the following was the set-up;
- Ramp was set at a θ angle, using a step (to create an incline plane)
- Two Photo-gates were set up in a row(at the base of the incline plane)
- A sort of car-like object -with a card to trigger the gates, was placed on the ramp and released
- The Photo-gates record the time triggered and released.
I can work out the values myself, I am asking If I have the correct variables, if so, how do I use them? and if not what am I missing and how would I use the variables if I had them
I cannot find a reasonable value for the coefficient of friction.
Variables:
Theta Angle of ramp = θ
Length of card on car-like object = l
Gate 1: Entry 1 = n1
Exit 1 = x1
Gate 2: Entry 2 = n2
Exit 2 = x2
Time = t
Gravity = g
Coefficient of friction = μ
Velocity = v
Mass = m
Displacement = s
Force = f
Acceleration = a
Equations of straight line motion,
K.E = 1/2mv2
Work = f*s
s = v2/2μg
a = vfinal - vinitial/t
I worked out the velocity the car-like object moved though both gates:
v1 = Before the car-like object is released
v2 = Whilst passing through the first gate
v3 = Whilst passing through the last gate
I then figured that the deceleration between gate 1 and 2 could be used to calculate the stopping time(the time it would take for the object to come to rest) by;
v3/deceleration
I then used this number to try and calculate the stopping distance through the equations of straight line motion and then mu through (s = v2/2μg), but kept getting a number of mu around 0.009, which seemed too small to be reasonable.
EDIT 1: The car-like object is a "Trolley" commonly used in physics experiements.
Please share your thoughts.
HappyScientist
An experiment was conducted to find the coefficient of friction on rubber, the following was the set-up;
- Ramp was set at a θ angle, using a step (to create an incline plane)
- Two Photo-gates were set up in a row(at the base of the incline plane)
- A sort of car-like object -with a card to trigger the gates, was placed on the ramp and released
- The Photo-gates record the time triggered and released.
I can work out the values myself, I am asking If I have the correct variables, if so, how do I use them? and if not what am I missing and how would I use the variables if I had them
Homework Statement
I cannot find a reasonable value for the coefficient of friction.
Variables:
Theta Angle of ramp = θ
Length of card on car-like object = l
Gate 1: Entry 1 = n1
Exit 1 = x1
Gate 2: Entry 2 = n2
Exit 2 = x2
Time = t
Gravity = g
Coefficient of friction = μ
Velocity = v
Mass = m
Displacement = s
Force = f
Acceleration = a
Homework Equations
Equations of straight line motion,
K.E = 1/2mv2
Work = f*s
s = v2/2μg
a = vfinal - vinitial/t
The Attempt at a Solution
I worked out the velocity the car-like object moved though both gates:
v1 = Before the car-like object is released
v2 = Whilst passing through the first gate
v3 = Whilst passing through the last gate
I then figured that the deceleration between gate 1 and 2 could be used to calculate the stopping time(the time it would take for the object to come to rest) by;
v3/deceleration
I then used this number to try and calculate the stopping distance through the equations of straight line motion and then mu through (s = v2/2μg), but kept getting a number of mu around 0.009, which seemed too small to be reasonable.
EDIT 1: The car-like object is a "Trolley" commonly used in physics experiements.
Please share your thoughts.
HappyScientist
Last edited: