Foundations Of Physics Flashcards
How is the uncertainty calculated when given a set of values of repeat readings?
Uncertainty=Range/2
Definition of Precise
A set of results/data is precise if the values are clustered closely together
Definition of Accuracy
A measurement is accurate if it is close to the true value
Tera
10^12 (T)
Giga
10^9 (G)
Mega
10^6 (M)
Kilo
10^3 (k)
Centi
10^-2 (c)
Milli
10^-3 (m)
Micro
10^-6 (µ)
Nano
10^-9 (n)
Pico
10^-12 (p)
Femto
10^-15 (f)
Deci
10^-1 (d)
cm^2—->m^2
Divide by 1x10^4
cm^3—->m^3
Divide by 1x10^6
Percentage Uncertainty
Percentage Uncertainty in a value= Uncertainty in Value/Value x 100
Random Error
What is it?
How does it affect results?
Random errors cause unpredictable fluctuations in an instrument’s readings as a result of uncontrollable factors such as environmental conditions. This affects the precision of the measurements taken, causing a wider spread of results about the value.
How to reduce random error?
To reduce random error, repeat measurements several times and calculate an average from them.
Systematic Error
Systematic errors arise from the use of faulty instruments used or from flaws in the experimental method. This type of error is repeated consistently every time the instrument is used or the method is followed which affects the accuracy of all the readings obtained.
How to reduce systematic errors?
-Instruments should be recalibrated, or different instruments should be used
-Corrections or adjustments should be made to the technique
What is zero error?
This is a type of systematic error which occurs when an instrument gives a reading when the true value is zero.