Pendulum Practical (1 Viewer)

[madboy1125]

I was reviewing for the physics practical and was looking at the pendulum practical. I have a practical workbook for physics and decided to make up results based on real values. I tried to calculate g but in the book, it said to create a graph of T^2 vs Length. I did this while coming with a gradient of 3.45.

I then calculated to find g by using: g=4π^2
Gradient

Ending up with a result of g=11.44 ms^-2

Please let me know what I did wrong. I can send you a picture of the graph if you want.

If you need a picture of the graph I can provide that.

Thanks
-Madboy1125

 

[photastic]

The reason why your value is much higher than the expected 9.8 is due to the errors of this experiment. You could consider the instability of the retort stand (if you used it) or the limitations of human reaction time. Perhaps you could've repeated the experiment for the same length to improve reliability (actually a more means to assess it tbh).

 

[madboy1125]

The reason why your value is much higher than the expected 9.8 is due to the errors of this experiment. You could consider the instability of the retort stand (if you used it) or the limitations of human reaction time. Perhaps you could've repeated the experiment for the same length to improve reliability (actually a more means to assess it tbh).

Also, one more thing. I tried searching on the internet for explanations for graphs. Some of them come up with Length on the y-axis and Period squared on the x-axis and vice versa. Which way is it?

Also the way I solved for g, it is correct not regarding the errors conducted in the practical?

 

[madboy1125]

bump.

 

[anomalousdecay]

You want:



You also want the gradient of the graph. Hence your y-axis is and your x-axis is .

As a result, you multiply the gradient of that graph by and the resulting experimental result you obtained for gravitational acceleration follows.

 

[Parvee]

iirc I did it this way
using

we get

plotting should give you a slope of 4 since

 

[anomalousdecay]

Both ways work I guess. However I like how Parvee's method gives you an indication of how off your results were and approximately by what factor.