Diagram:
Variables:
Dependant variable: Current (amps)
Independent variable: displacement of the wire.
Procedure:
Procedure:
- First of all I set the apparatus as shown above.
- Secondly I recorded the zero point of the end of the wire.
- Set the power supply to 12 Volts
- We recorded the displacement of the spring every 0.2 change in amps.
- We recorded the data and repeated the process twice. .
Data:
Average of trial 1 and 2
Trial 3
Length (L) = 0.805 m
Diameter of magnet = 0.05 m
Calculations
Slope of (average trial 1 and 2) = 2.275/1.2 = 1.895
Slope of trial three = 1.8 / 1 = 1.8
Average slopes = (1.895 + 1.8)/2 = 1.8475
(B x L x l)/ k = slope
B x 0.05 x 0.805 / k = average slopes
0.04025 B / k = 1.8475 (where k = 2 x 10 power -7)
201250B = 1.8475
B = 9.18 x 10 power -6
Conclusion and evaluation:
After examining the data I realized that the graphs had 2 point that were far from the best fit line. I also realized that these points were usually when the current exceeded 0.8 amps or when the spring was displaced more than 1.5 cm from its original position. Maybe this was due to the instability of the wire after this limit of either current or displacement.
In terms of possible errors our errors can be both random and systematic. Random error might have been caused from human parallax. Although we were careful about reading the answer from a perpendicular angle to the ruler, human’s eye has an uncertainty.
Our answers were slightly accurate but we can improve them simply by the repeating the trials more than two times and finding there average. Also we can be more careful during the collection of data to avoid parallax errors (an example was we didn’t record the starting point for one of the trials therefore all the data collected after that point in this trial was unreliable).
Finally looking back at my hypothesis I found out that the relation between the forces implied on the wire and the displacement is a linear function. More importantly the magnets effect wasn’t constant because as the current increased the displacement for the origin position increased.
