the true value of certain length is nearly 5.678cm in one expriement using measurement instrument ofa resolution 0.1cm the measurement value is found to be 5.5cm is another experiment using a measuring instrument of 8 greater resolution say 0.01 and the length is found to be 5.5cm is another experiment using a measuring instrument of 8 greater resolution say 0.01 and the length is found to be 5.38cm out of two instruments a and b which is more accurate and more precise
Answers
Explanation:
QUANTITIES - DEFINITION
Accuracy: The accuracy of a measurement is a measure of how close the measured value is to the true value of the quantity. The accuracy in measurement may depend on several factors, including the limit or the resolution of the measuring instrument.
For example, suppose the true value of a certain length is near 3.678cm. In one experiment, using a measuring instrument of resolution 0.1cm, the measured value is found to be 3.5 cm, while in another experiment using a measuring device of greater resolution , say 0.01 cm, the length is determined to be 3.38 cm. The first measurement has more accuracy because it is closer to the true value.
PRECISION - DEFINITION
Definition:
Precision is a measurement of the repeatability, or consistency, of a measurement. It is possible to have a very precise measurement without scatter (or noise) that is repeatable and would be considered precise (repeatable), however, it can be inaccurate because of an instrument error.
Example: Let us consider a weight measuring instrument which measures the weight of steel cube. Exact weight of the steel cube is 50 kg.
The instrument shows the weight of the cube as 47.819 kg, 47.823 kg, 47.835 kg and 47.847 kg.
From the above observations, we can conclude that the instrument has some precision since it almost reproduces same output value 47.8 kg. But the instrument does not have accuracy since the measured values are not close to the actual weight 50 kg.