Question

What is accuracy and precision? With examples.

Why do we take averages when there are more than one experiment ?

Answer 1

The closeness of a measured value to the actual value of the object being measured is called as accuracy of a substance. For instance, if in lab you obtain a weight measurement of 3.2 kg for a given substance, but the actual or known weight is 10 kg, then your measurement is not accurate.

The closeness of two or more measurements to each other is known as the precision of a substance. From the above given example we can figure out that, if you weigh a given substance five times, and get 3.2 kg each time, then your measurement is very precise. Precision is independent of accuracy.