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1) (6 points) You determine the resistance, R, of a resistor in two different wa

ID: 3279648 • Letter: 1

Question

1) (6 points) You determine the resistance, R, of a resistor in two different ways. Based on a measurement using a multimeter, you get Rmm-4511 ± 5 You also determine the resistance by running a known current through it and measuring the voltage across it. Using Ohm's law, you get Rohm-4499 ±4 . a) What is the discrepancy between the two measurements? b) Do the measurements agree? Why/why not? (Show your work) 2) (4 points) For each example below, w = A +B. What is w ow in standard format? a) A-(4.5 +0.1) x 10J B = (6.3 ± 0.2) x 10-2 J b) A-121-15 0.02 nm B-43.11 ±0.01 nm

Explanation / Answer

a)

The discrepancy is in the magnitude of Resistance of thhe resistor which is found to be in the range 4506 and 4516 ohms when measured by a multimeter and in the 4495 and 4503 range when measured by a known current flowing through it.

b)

No the values do not agree. By using a multimeter we get a range for resistance values that are higher than the value for resistance when measured by using a known current method.

The mulitmeter isa better way to measure the value of resistance as it is concealed in a case so the observational errors are minimized in comparison to the errors observed when we are applying a measured current and measuring voltage manually. There can be physical variations, instrument resolution differences, instrument drift etc and all of these contribute to more differences on measurement by a method.