 Level: International Baccalaureate
 Subject: Physics
 Word count: 853
To find the value of acceleration due to gravity by recording number of oscillations of a simple pendulum
Extracts from this document...
Introduction
Aditya Sareen
HL 1
Physics Lab 9
To find the value of acceleration due to gravity by recording number of oscillations of a simple pendulum
Satish Ahuja
XIIA
Physics HL 2
Raw Data
Meter Rule: Least count = 0.1 cm, uncertainty = 0.05cm
Vernier Calipers: Least count = 0.1cm, uncertainty = 0.05cm
Stopwatch: Least count = 1s, uncertainty = 0.5s
Table 1 – DATA9
Sr. No.  Length of string, l ± 0.05/cm  Time for oscillation, t ± 0.05/s 
1  20 
V. 9.3 
2  40 
V. 12.9 
3  60 
V. 15.1 
4  80 

5  100 

6  120 

7  140  I. 28.3 II. 28.5 III. 28.7 IV. 28.7 V. 28.4 
 The length of the string does not include the diameter of the bob 3.4 ± 0.05 cm)
 The number of oscillations = 10
Data Processing
Uncertainty Calculation
 The uncertainty of the ruler (± 0.05 cm) and half the uncertainty of the Vernier Caliper (± 0.05/2 = 0.025)
 Half of the uncertainty for the Vernier Caliper has to be taken as we have the diameter of the steel bob, and need only its radius.
 The example calculation for the length of string 0.2m is shown below:
Middle
Similarly, the calculations were performed for other readings
 An average of the time values(in s) for each reading was taken
 The calculation for the average time for string of length 20 cm is shown below:
Calculation 2
Averaging the uncertainties:
Therefore, our final answer stands as:
9.5 ± 0.5s
Rest of the calculations have been noted in the table below
Table 1.2 – Total Length and Average time for 10 oscillations
Sr. No  Total Length, n ± 0.525/cm  Average Time period for 10 oscillations, t± 0.5/s 
1  20  9.5 
2  40  12.44 
3  60  15.54 
4  80  18.68 
5  100  21.6 
6  120  25.22 
7  140  28.52 
 We then convert the time period for 10 oscillations to the time period for just one oscillation
 An example calculation using unitary method for the 1st time period is shown below
Example Calculation 3
Conclusion
Aspect 3
 A proper apparatus with a rigid support to suspend the string, along with an attached tape measure would reduce the random and systematic errors in this experiment
 More number of readings could be taken, and averaging them would negate most of the random errors in this experiment
This student written piece of work is one of many that can be found in our International Baccalaureate Physics section.
Found what you're looking for?
 Start learning 29% faster today
 150,000+ documents available
 Just £6.99 a month