https://padlet.com/firstyearlabs/magneticfluxdensity State your value for B with its uncertainty, suggest dominant sources of random and systematic error, and suggest improvements to reduce error. en-us 2022-10-07 10:16:54 UTC 2022-10-13 10:15:30 UTC hello@padlet.com https://padlet.net/icons/png/1f9f2.png https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2334985281 Possible errors from fluctuations in current, wire moving between measurements, wire being off-centred the whole time, offset error on balance, different height of blocks. Improvements would be to take repeat measurements, use spirit level, zero balance between measurements…]]> 2022-10-11 09:53:39 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2334985281 ppybh10 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2335046616 Mass balance is highly sensitive, so small changes such as leaning on the table can change result. This can happen inadvertently, and so is likely to cause errors.]]> 2022-10-11 10:47:19 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2335046616 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336735640 uncertainties:
calibration of equipment, current fluctuated between measurements (reduced by turning power supply off between readings)
zero error on scales
angle at which the wire is through the magnet, may not be 90 degrees

]]> 2022-10-12 09:41:38 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336735640 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336736868 Depending on if you used the power supply or multimeter to measure current you had different results. Also some of the rods were curved so you would get errors from that.]]> 2022-10-12 09:42:44 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336736868 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336738552 0.32T +/- 0.3

Systematic error- the precision of multimeter. Random error- positioning of the wire between the magnet.

The wire could be fixed more securely to keep it centered.]]> 2022-10-12 09:44:18 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336738552 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336743613 Sources of error:
Wire might move within the field
Calibration of equipment
Current on multimeter did not match current on power supply


]]> 2022-10-12 09:48:53 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336743613 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336744526 error could be from wire not being central, scales not properly calibrated or the precision of the multimeter ]]> 2022-10-12 09:49:42 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336744526 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336746248 Systematic error from the wire not being exactly equidistant between the two magnets. As well as the magnets not being exactly the same height. This could be fixed by using a vernier calliper to make sure the height and widths are more accurate. 

Systematic error came from the graph with the line of best fit not going through the origin.

]]> 2022-10-12 09:51:14 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336746248 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336820792 Knocks on the table might mess up the mass displayed slightly]]> 2022-10-12 11:01:05 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2336820792 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338458577 Sources of error: wire moving around slightly when cables are accidently jostled and having to be adjusted.

Improvement: Taping wires down to wooden blocks to avoid wires moving.]]> 2022-10-13 09:37:14 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338458577 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338462546 This measurement is clearly not correct as it is so far from all the other measurements which are in the order of 0.3T. There seem to be two main reasons for this:

Firstly, it is clear upon consideration of the graph (there seem to be two different lines of best fit) that the apparatus was knocked slightly before the 0.9A measurement was taken (we went from 0.3 to 1.5 in 0.1 A intervals). This systematically decreased the mass measurement which resulted in a shallower gradient. Since the gradient is proportional to B, then this decreased our value.

Secondly, the wooden blocks were slightly to high so the wire was not suspended into the centre of the B field. The force is not as strong in this region, again accounting for a systematic error that would decrease our final value of B.]]> 2022-10-13 09:40:32 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338462546 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338497457 Sources of error:
Fluctuation of multimeter
Movement of wire between readings
Misalignment of wire in magnet cradle
Zero error on scales
The current measurement on multimeter seemed to disagree with current display on source]]> 2022-10-13 10:09:55 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338497457 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338503124 Flux density: 0.27 +/- 0.02 T
Most uncertainty from the movement of the dial on the power supply being very sensitive.]]> 2022-10-13 10:15:09 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338503124 https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338503491 •Random error due to movement of wire during experiment - try not to lean on/move the desk during the experiment. Or, use blue tack to hold the wire in place.
•Systematic error caused by misalignment of wire in magnets - try to line the wire up as close to the red lines as possible.
•Systematic error from forgetting to zero balance - remove by subtracting mass of magnets and cradle from mass values.]]> 2022-10-13 10:15:30 UTC https://padlet.com/firstyearlabs/magneticfluxdensity/wish/2338503491