All the data you need is in the pictures. My professor told me to keep in mind y
ID: 1413369 • Letter: A
Question
All the data you need is in the pictures. My professor told me to keep in mind y=mx+b and mwg=(mc+mw)a +mc(g)(sin0) and y=(mc+mw)x and y= (m)(x) not sure what all that means but the slope is correct he said and I just need help with these 2 questions below:
1. DETERMINE PERCENT ERROR BETWEEN THE OBTAINED SLOPE AND ITS EXPECTED VALUE.
2. INCLUDE A SAMPLE ERROR CALCULATION. WHAT ARE POSSIBLE SOURCES OF ERROR?
All the data you need is in the pictures. My professor told me to keep in mind y=mx+b and mwg=(mc+mw)a +mc(g)(sin0) and y=(mc+mw)x and y= (m)(x) not sure what all that means but the slope is correct he said and I just need help with these 2 questions below:
1. DETERMINE PERCENT ERROR BETWEEN THE OBTAINED SLOPE AND ITS EXPECTED VALUE.
2. INCLUDE A SAMPLE ERROR CALCULATION. WHAT ARE POSSIBLE SOURCES OF ERROR?
Explanation / Answer
Percent error = |ameasured – atheoretical|×100/ atheoretical
Taking an example from the observation table is
ameasured = 1.057 N
atheoretical = 1.140 N
percent error = |1.057 – 1.140|×100/1.140
= |-7.28| 7.3%
2.
Sample error calculation:
The given expression of the question that calculates the theoretical value of acceleration a is given by
mwg = (mc + mw)a + mcgsin
=> a = {mwg - mcgsin}/(mc + mw)
=> a = gmw/(mc + mw) – gsinmc/(mc + mw)
For relative error propagation involving quotient of two quantities
Z = A/B
The relative error is given by
Z/Z = A/A + B/B
Applying the above formula in the expression for “a”, we have
a/a = g{mw/mw + (mw+mc)/(mw+mc )} + gsin{mc/mc + (mw+mc)/(mw+mc )}
mw, mc, (mw+mc) are least count error of mass balance
Since the least count of the mass balance is not given let’s consider it to be 1 g here.
mw = 1 g
mc = 1 g
(mw+mc) = 1 g
Sources of error here are measurements of masses mw and mc , evaluation of the angle of inclination .