Random error is caused by unpredictable fluctuations in the readings of the

Random error is caused by unpredictable fluctuations

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Random error is caused by unpredictable fluctuations in the readings of the measurement apparatus, or in the experiment’s interpretation of the instrumental reading. These fluctuations may be in part due to interference of the environment with the measurement process. 2.2.3 Systematic versus Random errors Random errors are always present in a measurement. It is caused by inherently un predictable fluctuations in the reading of the measuring instrument. Systematic errors cannot be discovered this way; it always pushes in the same direction. 2.3 Common Sources of Errors in Measurements
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13 There is no such thing as "human error "! This vague phrase does not describe the source of error clearly. Careful description of sources of error allows future measurements to improve on your techniques. This long list of common sources of error is meant to help you identify some of the common sources of error you might encounter while doing measurements. If you find yourself stuck for words when describing sources of error, this list may help. The list goes from the common to the obscure. i. Incomplete definition (may be systematic or random) - One reason that it is impossible to make exact measurements is that the measurement is not always clearly defined. For example, if two different people measure the length of the same rope, they would probably get different results because each person may stretch the rope with a different tension. The best way to minimize definition errors is to carefully consider and specify the conditions that could affect the measurement. ii. Failure to account for a factor (usually systematic) - The most challenging part of designing an experiment is trying to control or account for all possible factors except the one independent variable that is being analyzed. For instance, you may inadvertently ignore air resistance when measuring free-fall acceleration or you may fail to account for the effect of the Earth's magnetic field when measuring the field of a small magnet. The best way to account for these sources of error is to brainstorm with your peers about all the factors that could possibly affect your result. This brainstorm should be done before beginning the experiment so that arrangements can be made to account for the confounding factors before taking data. Sometimes a correction can be applied to a result after taking data, but this is inefficient and not always possible. iii. Environmental factors (can be systematic or random) - Be aware of errors introduced by your immediate working environment. You may need to take account for or protect your experiment from vibrations, drafts, changes in temperature, electronic noise or other effects from nearby apparatus. iv. Instrument resolution (random) - All instruments have finite precision that limits the ability to resolve small measurement differences. For instance, a meter stick cannot distinguish distances to a precision much better than about half of its smallest scale division (0.5 mm in this case). One of the best ways to obtain more precise
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