- Level: AS and A Level
- Subject: Science
- Word count: 2663
Lab Report - In this lab report, it will describe the weight of the bob, the displacement and the length of the string of how each factor affect the period of a pendulum.
Extracts from this document...
Introduction
Lab 3 - Pendulum
Introduction:
The pendulum consists of a string that has something hanging from the end. When the pendulum is pulled back and release from a certain displacement, the pendulum will freely swing down to the opposite side by force of the gravity and back. The length of the pendulum is measured by the distance from the point where the string is attached and down to the top of the bob. The period is the time it takes for the string to complete a number of required cycles. The cycle is the motion of the bob from the start point to the extreme opposite and back. The bob is the mass of the end of the string. The displacement is the distance or angle the bob is pulled to the right. In this lab report, it will describe the weight of the bob, the displacement and the length of the string of how each factor affect the period of a pendulum. This includes the hypothesis, methods, control variable, results, data table and the conclusion for each experiment.
Apparatus:
- Stop watch ± 0.01 seconds
- Ruler ± 0.05 cm
- Protractor ± 0.5°
- Scale ± 0.05 grams
- Ring Stand with a ring clamp attached
- String
- 3 Rubber Stoppers (Bob)
Middle
Lab 1 Part 2 – To determine how the displacement affect the period of a pendulum.
Hypothesis:
As the displacement increases, the period of the pendulum to swing one whole cycle will increase. The reason which could make this hypothesis true is that increasing the displacement is similar to creating a longer distance for the pendulum to swing back and forth. Such as, walking 10 m and back will be longer than walking 5 m and back. Thus having the pendulum swing a higher distance will most likely increase the period of the pendulum.
Methods:
- Obtain one rubber stopper (bob).
- Determine the mass of bob using the scale that measures to the nearest 0.05 grams
- Attach a string to the ring clamp.
- Attach a meter stick to the ring stand such that the zero on the scale is aligned with the point where the string is attached.
- Locate the 55 cm ± 0.05 on the scale of the ruler and attach the bob. Such that the top of the bob aligned with the point where it measures 55 cm ± 0.05.
- Remove the ruler.
- Attach a protractor in front of the ring clamp such that the vertex is aligned with the point where the string is attached.
- Angle the string to 70° cm ± 0.5 by pulling by the bob.
Conclusion
Discussion:
After completing three experiments with all three factors, weight of the bob, the change of displacement and the length of the string affected the period of a pendulum. The time increased as both the displacement and length of string increased. Considering both factors caused the pendulum to travel a longer distance increasing the period. The only increasing factor that causes the pendulum’s period to decrease is the weight of the bob. As the mass of the bob increases the period of the pendulum decreases, by increasing gravitational force from the mass of bob. The following table on Lab 3 – part 1, 2 and 3 had one factor of either the weight of the bob, the displacement and the length of the string (the independent variables). The tables show that each factor had an effect of the pendulum’s period (the dependant variable).The results was, when increasing the two factors, displacement or length of string increase the period of a pendulum. However, when increasing the mass of the bob, the period of the pendulum decreases. Either way, all three factors, weight of the bob, the displacement, and the length of the string affect the period of a pendulum.
This student written piece of work is one of many that can be found in our AS and A Level Fields & Forces section.
Found what you're looking for?
- Start learning 29% faster today
- 150,000+ documents available
- Just £6.99 a month