A-LEVEL Physics: 1.2.1: Sources of Uncertainty (SaveMyExams) Flashcards
Measurements of Quantities are Taken with the Aim of…
In reality, why is this impossible?
Finding the True Value of that Quantity.
In reality, this is impossible because there will Always be a Degree of Uncertainty.
What is ‘Uncertainty’?
Uncertainty is an Estimate of the Difference Between a Measurement Reading & the True Value.
___ & ___ Errors are Two Types of Errors that Lead to Uncertainty.
Random, Systematic.
What are ‘Random Errors’?
Random Errors are Errors that Cause Unpredictable Fluctuations in an Instrument’s Readings, as a Result of Uncontrollable Factors, eg Environmental Conditions.
Random Errors Affect the ___ of the Measurement Taken.
Precision.
To Reduce Random Error:
Repeat Measurements & Calculate an Average, to Reduce the Negative Effect of Anomolous Results.
What are ‘Systematic Errors’?
Systematic Errors are Errors Due to Faulty Equipment / Measuring Instruments, or the Method is Faulty.
Systematic Errors Affect the ___ of Reading Obtained.
Accuracy.
To Reduce Systematic Errors: (2)
-Recalibrate Instruments.
-Ensure the Method is Correct.
What is a ‘Zero Error’?
A Zero Error is a Type of Systematic Error, which Occurs when an Instrument Gives a Reading, when it should Display 0.
What Type of Error is Zero Error? Why?
Systematic Error. Because the Measuring Instruments are Faulty, Causing them to Display an Incorrect Reading, Instead of 0.
What is ‘Precision’?
Precisions is when all Measurements are Close to Each Other.
What is ‘Accuracy’?
Accuracy is how Close a Measurement is to the True Value.
Measurements Can be ___ but Not ___.
Precise, Accurate, Vice-Versa.
What is ‘Repeatability’?
An Experiment is Repeatable if the Original Person Repeats the Same Experiment, Using the Same Method & Equipment, & Obtaining the Same Results.
