AQA GCSE Physics Paper 2 Megaset Questions 100% Correct!!

A measurement result is considered accurate if it is judged to be close to the true value. - ANSWERAccuracy Marking a scale on a measuring instrument. This involves establishing the relationship between indications of a measuring instrument and standard or reference quantity values which must be applied. For example, placing a thermometer in melting ice to see whether it reads zero in order to check if it has been calibrated correctly. - ANSWERCalibration Information, either qualitative or quantitative, that has been collected. - ANSWERData The difference between a measured value and the true value. - ANSWERMeasurement error These are values in a set of results which are judged not to be part of the variation caused by random uncertainty. - ANSWERAnomalies These cause readings to be spread about the true value, due to results varying in an unpredictable way from one measurement to the next. Random errors are present when any measurement is made, and cannot be corrected. The effect of random errors can be reduced by making more measurements and calculating a new mean. - ANSWERRandom error These cause readings to differ from the true value by a consistent amount each time a measurement is made. Sources of systematic error can include the environment, methods of observation or instruments used. Systematic errors cannot be dealt with by simple repeats. If a systematic error is suspected, the data collection should be repeated using a different technique or a different set of equipment, and the results compared. - ANSWERSystematic error Any indication that a measuring system gives a false reading when the true value of a measured quantity is zero, eg the needle on an ammeter failing to return to zero when no current flows. A zero error may result in a systematic uncertainty. - ANSWERZero error Data which has been shown to be valid. - ANSWEREvidence A fair test is one in which only the independent variable has been allowed to affect the dependent variable. - ANSWERFair test A proposal intended to explain certain facts or observations. - ANSWERHypothesis