Research Question
- How do net force and mass effect acceleration on a system
- Experiment 1
- IV: Force on system
- DV: Acceleration of the cart
- Controls: mass of system, cart, track
- IV: Force on system
- Experiment 2
- IV: system mass
- DV: Acceleration of the cart
- Controls: Net force, cart, track
Procedure
All procedures were done on the pivot interactive online lab
- Friction less cart was placed on a track with a string attaching it to a set of weights. The string was placed through a wheel to minimize friction. This way the weights falling down would pull the cart to the end of the track.
- For experiment 1 the mass of the system was held constant while adjusting the hanging weight. Each trial the string was cut allowing the cart to be pulled down the track and the velocity was recorded. Weight was taken from the cart and moved to the hanger. This was done 5 times. The total weight of the system was kept constant at 400g with hanging weights from 0-100g used in increments of 20g.
- For experiment 2 the mass of the system was changed by maintaining a constant 100g hanging mass while changing the mass of the cart from 400-800g in 100g increments making 5 data points. Each trial the string was cut allowing the cart to be pulled down the track and the velocity was recorded.
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Example trial
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Data
- To calculate the force of the hanging mass the mass was multiplied by 0.0098N/g
- 20g*0.0098N/g=0.196N
- To calculate acceleration the equation X=Vi*t+.5at^2
- 41=0*1.4583+.5a(1.4583)^2
- a=2(41/1.4583^2)
- a=38.56m/s^2
Experiment 1
Acceleration cm/s/s=201.9 +/- 23.1 cm/s/s/N * Hanging mass force - 0.9195 +/- 13.72cm/s/s
Experiment 2
Acceleration cm/s/s=6.466*10^4 +/- 9818 cm/s/s/ System Mass
Conclusion
Experiment 1 showed the relationship between net force and acceleration. It showed that the relationship is linear and for every newton of force the cart will accelerate 201cm/s/s faster. The y intercept should be at 0 but the line of best fit has it at -0.9195m/s/s. This is because there are variances in the data that make the line of best fit not a 100% match. This may also be brought down by the data point at 0.392N. This point is much further below the line than the others. Outside of just this experiment it shows that the relationship between acceleration and Net force is a linear one.
Experiment 2 proved that the relationship between acceleration and mass is inverse. This was even seen with the outlier at 500g. This data point may have had the wrong video on the online lab.
These conclusions can turn into the formula F=ma where force is in newtons, mass is kilograms, and acceleration is in meters/s/s. This is because the newton is a derived unit.
The two largest sources of uncertainty in this lab were the fact there was only one trial on video and the ruler does not have very specific measurements. Because pivot only recorded one video of each weight it is impossible to conduct multiple trials. This makes issues such as the outlier in experiment 2 at 500g possible. At this data point the expected acceleration is much higher than it actually was but considering the trends from the rest of the data this was likely because the trial in the video was flawed or the wrong video is linked to that trial. The accuracy of the lab could be greatly improved if there were multiple trials of each system mass and hanging mass combination. This would allow for the trials to be averaged to get more accurate data and trends. Another issue is that the ruler does not have very specific measurements. This while probably a smaller issue doesn't allow very accurate data to be taken as the rule only goes to the cm place. There are no mm so the exact location of the cart when the weight hits the ground cannot be determined.
Experiment 2 proved that the relationship between acceleration and mass is inverse. This was even seen with the outlier at 500g. This data point may have had the wrong video on the online lab.
These conclusions can turn into the formula F=ma where force is in newtons, mass is kilograms, and acceleration is in meters/s/s. This is because the newton is a derived unit.
The two largest sources of uncertainty in this lab were the fact there was only one trial on video and the ruler does not have very specific measurements. Because pivot only recorded one video of each weight it is impossible to conduct multiple trials. This makes issues such as the outlier in experiment 2 at 500g possible. At this data point the expected acceleration is much higher than it actually was but considering the trends from the rest of the data this was likely because the trial in the video was flawed or the wrong video is linked to that trial. The accuracy of the lab could be greatly improved if there were multiple trials of each system mass and hanging mass combination. This would allow for the trials to be averaged to get more accurate data and trends. Another issue is that the ruler does not have very specific measurements. This while probably a smaller issue doesn't allow very accurate data to be taken as the rule only goes to the cm place. There are no mm so the exact location of the cart when the weight hits the ground cannot be determined.