~Pendulum~

Bil Name Matrics No.

1. Nik Ikhwan Bin Nik Li D20101037491

2. Muhammad Yunus Bin Hamid D20101037440

3. Muhammad Riyadh Bin Roslan D20101037482

~Engage~

Does length of string affect the period of oscillation?

•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?

How to avoid damping?

What other application that similar to pendulum?

What can you get from observing the experiment?

What is the graph shape?

~EMPOWER~

DATA FINDINGS

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

Figure 1

Data Studio Software

Pendulum and sensor

•Result

Graph of Angular Positon (°) Againts Time (s) For String Length 20 cm

•Result

Graph of Angular Positon (°) Againts Time (s) For String Length 10 cm

Data analysis

Length of String (l)

Time taken to complete 20 0scilations

Period, T

20 cm 19.23 s 0.96 s

10 cm 15.89 s 0.79 s

From the graph obtained, we can conclude the data as table below

Data analysis

Gravity calculation

Equation 1

  Equation 2

Data analysisGravity calculation

By substitute the data into the equation

Data analysisGravity calculation

From the experiment, the gravitational value obtained was ,

The theoretical value for the gravitational acceleration is

Data analysisGravity calculation

Formula for "Percentage Error":

(The "|" symbols mean absolute value, so negatives become positive)

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.

• 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)

• 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.

Conclusion

~Enhance~

APPLICATION OF PENDULUM.

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??

Which Rope should the Fireman Use??

5 meter 7 meter

Why??

Explain?

How to make this Item Swing for Long time?

Application

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.

Which one is good for your baby??

• 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.