Expanded Uncertainty
Compute the expanded uncertainty of a measurement, U = k · uc, multiplying the combined uncertainty (uc) by the coverage factor k. While the combined uncertainty corresponds to ~68% confidence (1σ), the expanded one defines a higher-confidence interval — with k = 2, about 95%, the standard in most calibration certificates. It is the final value reported as '± U' in the result. Enter the coverage factor k and the combined uncertainty.
Resultado
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Incerteza expandida
Toda medição tem incerteza — a questão é com que confiança reportá-la. A incerteza combinada (uc), obtida combinando todas as fontes de erro, corresponde a um nível de ~68% (1σ): a probabilidade de o valor verdadeiro estar nesse intervalo é só de dois terços. Para os certificados de calibração, isso é pouco. Multiplica-se então por um fator de abrangência k: U = k·uc. Com k = 2, o intervalo cobre ~95% (o padrão mundial); k = 3 dá ~99,7%. O resultado final é reportado como 'valor ± U', e a incerteza expandida é o número que o cliente do laboratório de fato usa. Informe o fator k e a incerteza combinada.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.