This present post is in continuation with what are the errors in physics and here we are going to discuss further types of errors.
We do measure different physical quantities like velocity,acceleration,force and work done and the list goes on in physics during our experimentation.During their measurement errors do occur and we have to minimize them.
RANDOM ERRORS :
They are due to uncontrolled disturbances which influence the physical quantity and the instrument.
Ex-:The errors due to line voltage changes and backlash error.
Backlash errors are due to screw and nut.
GROSS ERRORS :
The cause for gross errors are improper recording, neglect of the sources of the error, reading the instrument incorrectly, sheer carelessness .
Ex: In a tangent galvanometer experiment, the coil is to be placed exactly in the magnetic meridian and care should be taken to see that no other magnetic material are present in the vicinity.
No correction can be applied to these gross errors.
When the errors are minimized, the accuracy increases.
The systematic errors can be estimated and observations can be corrected.
Random errors are compensating type. A physical quantity is measured number of times and these values lie on either side of mean value-with random errors. These errors are estimated by statistical methods and accuracy is achieved.
Personal errors like parallax error can be avoided by taking proper care.
The instrumental errors are avoided by calibrating the instrument with a standard value and by applying proper corrections.
True value and Errors
In the measurement of a physical quantity the arithmetic mean of all readings which is found to be very close to the most accurate reading is to be taken as True value of the quantities.
Absolute Errors :
The magnitude of the difference between the true value of the measured physical quantity and the value of individual measurement is called absolute error.
Absolute error is equal to |True value - measured values|
The absolute error is always positive.
The arithmetic mean of all the absolute errors is considered as the mean absolute error or final absolute error of the value of the physical concerned and it is also positive.
Relative error:
The relative error of a measured physical quantity is the ratio of the mean absolute error to the mean value of the quantity measured.
RELATED POSTS
We do measure different physical quantities like velocity,acceleration,force and work done and the list goes on in physics during our experimentation.During their measurement errors do occur and we have to minimize them.
RANDOM ERRORS :
They are due to uncontrolled disturbances which influence the physical quantity and the instrument.
Ex-:The errors due to line voltage changes and backlash error.
Backlash errors are due to screw and nut.
GROSS ERRORS :
The cause for gross errors are improper recording, neglect of the sources of the error, reading the instrument incorrectly, sheer carelessness .
Ex: In a tangent galvanometer experiment, the coil is to be placed exactly in the magnetic meridian and care should be taken to see that no other magnetic material are present in the vicinity.
No correction can be applied to these gross errors.
When the errors are minimized, the accuracy increases.
The systematic errors can be estimated and observations can be corrected.
Random errors are compensating type. A physical quantity is measured number of times and these values lie on either side of mean value-with random errors. These errors are estimated by statistical methods and accuracy is achieved.
Personal errors like parallax error can be avoided by taking proper care.
The instrumental errors are avoided by calibrating the instrument with a standard value and by applying proper corrections.
True value and Errors
In the measurement of a physical quantity the arithmetic mean of all readings which is found to be very close to the most accurate reading is to be taken as True value of the quantities.
Absolute Errors :
The magnitude of the difference between the true value of the measured physical quantity and the value of individual measurement is called absolute error.
Absolute error is equal to |True value - measured values|
The absolute error is always positive.
The arithmetic mean of all the absolute errors is considered as the mean absolute error or final absolute error of the value of the physical concerned and it is also positive.
Relative error:
The relative error of a measured physical quantity is the ratio of the mean absolute error to the mean value of the quantity measured.
RELATED POSTS
No comments:
Post a Comment