• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5
6. 6
6
7. 7
7
8. 8
8
9. 9
9
10. 10
10
11. 11
11
12. 12
12
13. 13
13
14. 14
14
15. 15
15
16. 16
16
17. 17
17

# OCR B Advancing Physics Physics Practical Investigation Coursework Investigating Simple Harmonic Oscillations

Extracts from this document...

Introduction

Physics Practical Investigation Coursework

Investigating Simple Harmonic Oscillations

This investigation aims to explore the nature of different oscillating systems, including the factors upon which the oscillation depends and the energy transfer involved.

Preliminary Experiment

A pendulum was made using a bob hanging, by a piece of string, from a standing clamp. Experiments were carried out, recording the time taken for ten complete cycles from angles of displacement ranging from 5 to 30° in 5° intervals.  In separate experiments, the mass and string length were changed as the independent variables in order to investigate the effect they had upon the period of oscillation. The mass of the bobs used were 100, 200 and 300g; the length of the string varying between 15cm and 30cm. For each experiment, three trials were completed in order to allow identification of anomalous results and enable the calculation of an average time – this value was then divided by ten in order to work out the average time of one oscillation.

 Length of string: 0.15m Average time for 1 oscillation (s) Amplitude: Angle of initial displacement (degrees) 100g 200g 300g 5 1.08 1.08 1.09 10 1.08 1.09 1.09 15 1.09 1.09 1.09 20 1.08 1.09 1.08 25 1.09 1.10 1.09 30 1.09 1.10 1.09 Length of string: 0.3m Average time for 1 oscillation (s) Amplitude: Angle of initial displacement (degrees) 100g 200g 300g 5 1.31 1.32 1.31 10 1.32 1.33 1.32 15 1.32 1.33 1.32 20 1.32 1.33 1.33 25 1.33 1.33 1.33 30 1.33 1.34 1.33

For complete table of data, see appendix.

Middle

A source of error could be that the surface area of the hanging mass does not remain constant – meaning there could be additional friction between mass and fluid with larger masses and consequentially a greater loss of energy.

The effect of the damping can be seen more easily by comparison between the two experiments.

As can be seen in the graph, the resonant frequency is consistently lower in the damped system than in the undamped system.

 Mass (kg) Undamped Average ResonantFrequency (Hz) Damped Average ResonantFrequency(Hz) Difference (Hz) % Difference 0.10 2.57 2.00 0.57 22.08 0.15 2.38 1.80 0.58 24.48 0.20 2.12 1.65 0.47 22.05 0.25 2.00 1.45 0.55 27.50 0.30 1.90 1.39 0.51 26.67 0.35 1.80 1.31 0.49 27.41 0.40 1.70 1.23 0.47 27.45

The damping effect reduces the resultant frequency by an average of 0.52Hz. The percentage decrease in resonant frequency increases slightly with mass – possibly due a greater surface area of larger masses as discussed above.

To calculate an approximatepercentage change, where the lines of best fit are almost equal in gradient (0.4 and 0.44), the first point was removed. The intercepts differ by 7.92 meaning that, over this range of values, the amplitude is reduced by approximately 8cm by the damping effect of the water. As a percentage change this is:     (8/8.81) x 100 = 91%.

The reason that, in reality, the difference is not linear (especially in the undamped) system is the square relationship between amplitude and energy (E=1/2 kx2).

Conclusion

an>

Trial 2

Trial 3

Average

Average time for 1 oscillation

5

10.71

10.80

10.82

10.78

1.08

10

10.82

10.80

10.92

10.85

1.08

15

10.86

10.87

10.86

10.86

1.09

20

10.83

10.82

10.87

10.84

1.08

25

10.88

10.90

10.90

10.89

1.09

30

10.87

11.00

10.93

10.93

1.09

Length 15cm

Time taken for 10 oscillations

Mass 200g

Angle of initial displacement (degrees)

Trial 1

Trial 2

Trial 3

Average

Average time for 1 oscillation

5

10.74

10.84

10.89

10.82

1.08

10

10.90

10.93

10.95

10.93

1.09

15

10.89

10.84

10.90

10.88

1.09

20

10.84

10.93

11.01

10.93

1.09

25

10.98

11.00

10.93

10.97

1.10

30

11.02

11.02

11.02

11.02

1.10

Length 15cm

Time taken for 10 oscillations

Mass 300g

Angle of initial displacement (degrees)

Trial 1

Trial 2

Trial 3

Average

Average time for 1 oscillation

5

10.76

10.80

11.01

10.86

1.09

10

10.84

10.79

10.92

10.85

1.09

15

10.82

10.90

10.86

10.86

1.09

20

10.80

10.89

10.85

10.85

1.08

25

10.84

10.90

11.01

10.92

1.09

30

10.89

11.00

10.90

10.93

1.09

 Trial 1 Trial 2 Trial 3 Undamped Mass (kg) Resonant Frequency Amplitude of Resonant Frequency Resonant Frequency Amplitude of Resonant Frequency Resonant Frequency Amplitude of Resonant Frequency Average Resonant Frequency Average Amplitude of Resonant Frequency 0.10 2.60 5.00 2.60 5.50 2.50 5.50 2.57 5.33 0.15 2.40 9.50 2.40 9.00 2.35 9.00 2.38 9.17 0.20 2.10 10.00 2.15 10.20 2.10 10.60 2.12 10.27 0.25 2.00 10.20 2.00 10.50 2.00 11.20 2.00 10.63 0.30 1.90 10.90 1.90 11.20 1.90 11.25 1.90 11.12 0.35 1.80 11.00 1.80 11.40 1.80 11.30 1.80 11.23 0.40 1.70 11.20 1.70 11.30 1.70 11.45 1.70 11.32 Trial 1 Trial 2 Trial 3 Damped Mass (kg) Resonant Frequency Amplitude of Resonant Frequency Resonant Frequency Amplitude of Resonant Frequency Resonant Frequency Amplitude of Resonant Frequency Average Resonant Frequency Average Amplitude of Resonant Frequency 0.10 2.00 1.50 2.00 1.50 2.00 1.60 2.00 1.53 0.15 1.80 2.20 1.80 1.60 1.80 1.70 1.80 1.83 0.20 1.70 3.00 1.60 2.00 1.65 2.00 1.65 2.00 0.25 1.45 2.30 1.45 2.60 1.45 2.10 1.45 2.33 0.30 1.40 3.00 1.40 3.30 1.38 3.70 1.39 3.15 0.35 1.32 3.60 1.30 3.60 1.30 3.50 1.31 3.57 0.40 1.25 4.00 1.20 4.20 1.25 4.00 1.23 4.07

Anomalous results (in red) are not included in averages.

This student written piece of work is one of many that can be found in our AS and A Level Mechanics & Radioactivity section.

## Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Related AS and A Level Mechanics & Radioactivity essays

1. ## AS OCR B Advancing Physics Coursework - Making Sense of Data

4 star(s)

Due to the fact that the object seems to be moving with a constant acceleration I have next decided to explore this value acceleration of the falling mass due to gravity. I believe this figure will be most accurately obtained through graphical methods by working out the gradient of a

2. ## The Physics of Windsurfing

4 star(s)

piece of monofilament fishing line * one 15-cm (6") straw * two 7.5-cm (3") straws 1. Fold one sheet of paper in half, but do not crease the fold. 2. Tape the long opened edge of paper with three small pieces of tape to keep it closed. This taped side will be known as your "trailing edge," while the folded side will be known as the "leading edge."

1. ## Catapult Investigation

3 star(s)

The elastic band was then pulled back at a force of 9 Newton's. The elastic band was then pulled back at a force of 10 Newton's. In total 50 tests results were recorded. We measured the distance that the weight was fired with the metre rulers and lined them up using the set square.

2. ## Science 1 Investigating thedeflection of a cantilever.

1g weights. We find that with increase in force in Newton's there is a similar increase in the deflection of the ruler in approximately 0.8cm/g of weight. These results are as expected. The graph shows a straight line and there is ~0.8 cm increase in deflection.

1. ## Physic lab report - study the simple harmonic motion (SHM) of a simple pendulum ...

is angular velocity v = ? A sin ?t a = - ?2A cos ?t Period T = 2 ? / ? In theory, the displacement-time, velocity-time and acceleration-time graphs should be in a sine or cosine curve. Moreover, the velocity graph should lead the displacement by a quarter of the cycle (?

2. ## Use of technology in a hospital radiology department. The department of imaging is one ...

The purpose of each is briefly described below. Camera collimator, this is the first place that an emitted gamma photos encounters after exiting the body. The collimator is a pattern of holes through gamma ray absorbing material, usually lead or tungsten that allows the projection of the gamma ray image onto the detector crystal.

1. ## Force of Friction experiment

This was because the brick surface was too rough that it was actually not a flat surface. Additional force is required to move the block up and down. The motion was not sliding at all. Therefore the theory of 0<<1 does not hold in this case.

2. ## The Physics of an Atomic Bomb

Generally though, slow-fissionable isotopes are more fissionable than fast-fissionable isotopes for neutrons of all energies. A general trend among the elements is that the ratio of neutrons to protons in an atomic nucleus increases with the element's atomic number (the number of protons the nucleus contains, which determines which element it is).

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to