Current 0.35A Absolute uncertainties were as follows Uncertainty in voltmeter 0.01v Uncertainty in ammeter 0.01A Uncertainty in the cross sectional area of wire- The wire was measured three times along its length with a digital micrometer and a mean taken. The readings l/m pd/V were as follows 0.100 0.68 0.200 1.30 m 0.300 1.75 0.248 0.252 0.254 0.251 0.400 2.39 0.500 2.80 0.600 3.65 Uncertainty in a range of readings is half the range of the spread of 0.700 4.00 results so 0.800 4.67 0.900 5.52 This is the absolute uncertainty in the diameter of the wire ±0.003mm. We need the diameter in the area and the area is so radius is = 4.95x10-8 m2 -because the radius is squared we have to take the uncertainty into account twice. However, we just add absolute uncertainties; rather, we have to add the percentage can’t uncertainties.
l/m pd/V 0.100 0.68 0.200 1.30 0.300 1.75 0.400 2.39 0.500 2.80 0.600 3.65 0.700 4.00 0.800 4.67 0.900 5.52 Current 0.35A Absolute uncertainties were as follows Uncertainty in voltmeter 0.01v Uncertainty in ammeter 0.01A Uncertainty in the cross sectional area of wire- The wire was measured three times along its length with a digital micrometer and a mean taken. The readings were as follows 0.248 0.252 0.254 0.251 Uncertainty in a range of readings is half the range of the spread of results so This is the absolute uncertainty in the diameter of the wire ±0.003mm. We need the diameter in the area and the area is so radius is = 4.95x10-8 m2 -because the radius is squared we have to take the uncertainty into account twice. However, we can’t just add absolute uncertainties; rather, we have to add the percentage uncertainties. m