The document describes an experiment to determine the effect of string length on the period of a pendulum. Data was collected using a motion detector as the pendulum swung with string lengths of 20 cm and 10 cm. The period was calculated from the time taken to complete 20 oscillations. The results showed that longer string lengths had longer periods. Gravity was also calculated and had a small percentage error compared to the theoretical value.

1. ~Pendulum~
Bil Name Matrics No.
1. Nik Ikhwan Bin Nik Li D20101037491
2. Muhammad Yunus Bin Hamid D20101037440
3. Muhammad Riyadh Bin Roslan D20101037482

2. ~Engage~
Does length of string affect the period of
oscillation?

3. •Pendulum is a hypothetical pendulum suspended by a weightless frictionless thread
of constant length.
•The pendulum’s period is tested by using different length of string.
•Which length of string that slower and faster the period of the pendulum’s
oscillation?

4. What other What can you get
application that from observing
similar to the experiment?
pendulum?
What is the graph
How to avoid shape?
damping?

5. ~EMPOWER~
DATA FINDINGS

6. PROCEDURE
1. The apparatus was set up as shown in figure 1.
2. The length of the string that attach to the
constant mass was set as 20 cm length.
3. The pendulum is displaced so that it performed
oscillation of simple harmonic motion.
4. The data were recorded automatically by using
motion detector.
5. Stop the experiment after the pendulum has make
20 oscillations.
6. The period T for the 20 oscillations were
determined.
7. The experiment was repeated by substituted the
length of the string by using 10 cm length

7. Figure 1

8. Data Studio Software

9. Pendulum and sensor

10. • Result
Graph of Angular Positon (°) Againts Time (s) For
String Length 20 cm

11. • Result
Graph of Angular Positon (°) Againts Time (s) For
String Length 10 cm

12. Data analysis
From the graph obtained, we can conclude the data
as table below
Length Time taken Period, T
of String to
(l) complete
20
0scilations
20 cm 19.23 s 0.96 s
10 cm 15.89 s 0.79 s

13. Data analysis
Gravity calculation
Equation 1
Equation 2

14. Data analysis
Gravity calculation
By substitute the data into the equation

15. Data analysis
Gravity calculation
From the experiment, the gravitational value
obtained was ,
The theoretical value for the gravitational
acceleration is

16. Data analysis
Gravity calculation
Formula for " Percentage Error":
(The "|" symbols mean absolute value, so negatives become positive)

17. Discussion
• From the experiment, we use data logger as the medium to detect
the time and the angular positions of the pendulum
• From the graph, the time to complete 20 oscillations can be
determine. The period calculated using time to complete 20
oscillations divided by 20.
• The time taken 20 oscilation for 20 cm l string was 19.23 s and the
time taken for 10 cm string was 15.89 s. from the formula below
The time taken for oscillation, T is directly proportional to the string
length, l. Therefore, the longer the l, the longer the T.

18. • By using the formula:
The acceleration of gravity is calculated was
• The percentage error calculated in this
experiment is
• This indicated that there were some errors that
occurred during the experiment process. There
errors could be:
1) Air resistance (solution: do the experiment
at the vacuum condition)
2) Human error (solution: measured the length
of l precisely and carefully)

19. Conclusion
• From the experiment, the value of gravitational
acceleration obtained is is percentage
error compare to the theoretical value which is
• The longer the length of string, the longer the period for
oscillation taken.
• The data login application used was Data Studio which
the data reading taking automatically by the computer.

20. ~Enhance~
APPLICATION OF PENDULUM.

21. Case
Firefighters had to rescue a boy aged 10 that
carried by the water flow to other side of river.
Which rope should be used by the firefighters to
get to the other side in the short time??

22. Which Rope should the Fireman Use??
5 meter 7 meter
Why??
Explain?

24.  In this experiment that shown by the graph, the
longer the string, it will take longer time to stop.
 This item swing longer if we can increase the length
of string.
 We can save our energy to and can just look it swing
in our office.
 Increase the length will make this decorative item will
make it swing for a longer period.

26. • The baby will move their body during they sleep. So this
cradle will swing because it follows principle of pendulum.
• Swinging may make disturb the baby and make them wake up
and cry
• Based on the experiment we know that, when we release the
ball, the shorter string will make a shorter time to complete
one oscillation
• We know that picture A have long string and near to the
ground compare to picture B which is have shorter string.
• The cradle A will swing slowly compare to cradle B that may
swing from side to side more faster which can disturb your
baby when sleep.