Civil Engineering - Surveying - Discussion

Here short chain measure 30.01 meters.

So error =30.01-30=+0.01 hence answer is a positive cumulative error.

Chain is too short i.e postive cumulative error.
Chain is too long i.e negative cumulative error.
So, the answer is postive cumulative.

Answer C is correct because they already declared that the tape is 30 m but the distance measured is less than the tape length by 0.01m. Hence it is positive cumulative error.

If an elongated chain (suppose 2 metres too long) is kept on the ground. It will cover a distance of 32 metres but it will show you the 30-metre distance.

The Correct answer is a positive commutative error.

Error =measured length - true length.
When the chain is too short ML >T. L.
SO, ERROR IS POSITIVE and it is commutative because every time we are using the same chain means we are adding.

{ POSITIVE ERROR }:: 'Measured length is "more than" the actual length.
The length of the chain is "shorter than " the standard length.
The temperature is "lower than" at which the tape was calibrated.

{NEGATIVE ERROR}:: 'Measured length is less than the actual length.
The length of the chain is greater than the standard length.

{COMPANSATIVE ERROR }:: 'Incorrect holding of the chain.
'Variation in pull.