PHY 1200 Foundation Physics Errors/Uncertainties and Dimensional Analysis PDF

PHY 1200 Foundation Physics Errors/Uncertainties and Dimensional Analysis Mr. Vishal Hemraj  Errors/Uncertainties Absolute Uncertainty – the absolute uncertainty is the number which, when combined with a reported value, gives the range of true values.eg. 2.45cm +/- 0.01 cm This means that the...

PHY 1200 Foundation Physics Errors/Uncertainties and Dimensional Analysis Mr. Vishal Hemraj  Errors/Uncertainties Absolute Uncertainty – the absolute uncertainty is the number which, when combined with a reported value, gives the range of true values.eg. 2.45cm +/- 0.01 cm This means that the measurement is somewhere between 2.44cm and 2.46cm Absolute uncertainty is dependent on the instrument used. Absolute Uncertainty may have a unit. Errors/Uncertainties  Errors/Uncertainties Relative Uncertainty – The relative uncertainty is the ratio of the absolute uncertainty to the reported value. Eg. The relative uncertainty of a length 2.45cm+/-0.01cm is Relative uncertainty is dependent on the absolute uncertainty and the reported value Errors/Uncertainties Percentage Uncertainty- Percentage uncertainty is the product of the relative error and 100%. Rules for Operating with Errors/Uncertainties Whenever adding or subtracting measurements, the absolute uncertainties are always added.  Rules for Operating with Errors/Uncertainties Whenever multiplying or dividing measurements, the relative or percentage uncertainties are always added.  Rules for Operating with Errors/Uncertainties When dealing with formulas with exponents, multiply the percentage/relative uncertainty of the measurement by the exponent. Eg Since the exponent ,‘2’, is attached to ‘r’ and. The uncertainty of the area will therefore be  Dimensional Analysis Dimensions refers to the type of base quantities that make up it up and each are represented by their own unique symbols. Dimensions can be used as a help in working out relationships, a procedure referred to as dimensional analysis. One useful technique is the use of dimensions to check if a relationship is correct (homogeneity). (Giancoli, 2014) Dimensional Analysis Dimensions (base) Symbols Length [L] Mass [M] Time [T]  Example What are the dimensions for density?  References Azuan, A. (2020, January 13). Math is Everywhere!!: Topic 1: Indices. Retrieved from Math is Everywhere: http://azimazuan.blogspot.com/2016/06/indices.html Bauer, W., & Westfield, G. D. (2011). Univeristy Physics. New York: McGraw Hill Companies, Inc. Giancoli, D. C. (2014). Physics, Principles with Applications. Boston: Pearson Education Inc. Woodside, R. (2019). Physics: Cambridge Internationa AS and A level (Revision Guide). London: Hachette UK Company.