Question 4: What are errors? Differentiate between systematic and random errors?
Definition of error
Error is the difference between the true value of the quantity and the measured value by the experimenter.
No matter how sophisticated the measuring instrument is or how carefully the measurement is taken, there is always a doubt of error. Therefore, every measurement is taken only approximate.
Types of errors (Differentiation)
There are two major types of errors, depending upon the possible source of error. They are systematic errors and random errors.
- Systematic Error: Systematic errors are further divided into tow groups.
- Instrumental Errors: Imperfect design or poor calibration etc are the main sources of instrumental errors.
- Personal Errors: Personal errors arise due to the carelessness, biases or improper knowledge about the instrument by the experimenter.
- Random Error: Errors which occur randomly (accidently) are called random errors. These are irregular errors and hence the size (magnitude) and direction cannot be predicted. Source of such errors is usually, experimental conditions (like temperature, humidity etc.).
Do you know what is personal biases in measurement
Yes, some time people have personal liking and disliking, called bias. They stress on (and wish) the result to be according to their liking. This attitude of the experimenter adversely affects the measurement. So, one should be quite impartial and neutral while carrying out measurement in science.