# Physics HL IA (18/24)

본 문서는 실제 IB May 2022에 제출했던 물리 IA이며, 주제는 “What is the effect of the height of the pendulum bob from the end of the string on the period of the pendulum to determine the value of ‘g’?”입니다. 받은 점수는 18/24점 입니다.

[본문내용]

### Title: Conical Pendulum Experiment

Introduction:

In my Theory of Knowledge class, we discussed the Flat Earth Society, and my teacher asked me how we could prove that the Earth was not flat. I said, “If the Earth was flat, the acceleration due to gravity must vary significantly, as we move further away from the edge of the Earth. But its value is almost constant everywhere because it is a spheroid.” However, I soon realized that I was contradicting myself because I kept on making assumptions and was reliant on what I had been told. In science, we commonly assume the gravitational acceleration to be 9.81 ms-2, neglecting the slight changes in the value. I did not want to accept this for granted, so decided to investigate the acceleration due to gravity.

In order to determine the gravitational acceleration, the relationship between the period of a pendulum and the height of the bob can be investigated. I first used a simple harmonic pendulum, but it was found to slow down a lot due to the damping effect. So, I switched the apparatus to the motor-driven conical pendulum which completes revolutions at a constant speed and prevents the effect of damping on the period. When the motor-driven pendulum was attempted, it provided a more stable circular motion, which was easier to record the period of the pendulum. In addition, I attempted changing the length of the pendulum string to change the height for my independent variable. However, it was hard to adjust the height to a certain value. To improve on this problem, the voltage of the rotational motor was changed instead, to cause a change in the height of the pendulum.

Research Question:

What is the effect of the height of the pendulum bob from the end of the string on the period of the pendulum to determine the value of ‘g’?

• 총 페이지수: 12 pages
• 과목명: Physics
• 주제: What is the effect of the height of the pendulum bob from the end of the string on the period of the pendulum to determine the value of ‘g’?
• The file is in Word format.