The resistance of a resistor is measured using a voltmeter and an ammeter. The voltage measurements have a mean value of 1V and standard deviation of 0.12 V

Q. The resistance of a resistor is measured using a voltmeter and an ammeter. The voltage measurements have a mean value of 1V and standard deviation of 0.12 V while current measurements have a mean value of 1 mA with standard deviation of 0.05 mA. Assuming that the errors in voltage and current measurements are independent, the standard deviation of the calculated resistance value is__________W .

Sol:

Voltage measurements: X1 = 1 V, σ1 = 0.12 V

Current measurements: X2 = 1 mA, σ2 = 0.05 mA

% σ1 = 12, % σ2 = 5

Standard deviation in resistance measurement