Report Writing

In Science whenever an experiment is completed, a report on that experiment could be written. A scientific report gives a clear and concise explanation of how to complete the experiment as well as presenting the results in an appropriate format. In order to write a clear and concise report, the structure below can be used:-


Aim:

To investigate how the (independent variable) affects (dependent variable).

For example : To investigate how the Volume of Water affects the Time Taken to boil


Independent variable:

The factor which you are varying, how you would measure it and its units.

For example : The Volume of Water, measured using a Measuring Cylinder in ml.


Dependent variable:

The factor which changes as a result of you changing the independent variable, how you would measure it and its units.

For example :The Time taken to boil, measured using a stopwatch in seconds.


Variables kept constant:

These are all the factors which you will not change. This makes the experiment valid.

For example :

  1. Liquid used

  2. Size of container

  3. Material of container

  4. Starting Temperature


Measurements/Observations to be made:

These are all the factors which you will measure in the Experiment. These Include the Variables above as well as any other measurements needed.

For example :

  1. The volume of water, measured using a measuring cylinder in ml .

  2. The Temperature of the water, measured using a Thermometer in °C.

  3. The Time taken to boil, measured using a stopwatch in s.


Resources:

A list of all equipment required for the experiment

For example :

  1. Tripod

  2. Bunsen Burner

  3. Heat Proof Mat

  4. 100 ml Glass Beaker

  5. 100 ml Measuring Cylinder

  6. Liquid in Glass Thermometer

  7. Stopwatch


Health and Safety:

A list of safety rules required for the experiment

For example :

  1. Fire Safety - Bunsen Burner Should be lit following the teacher's instructions. Desk around Bunsen Burner should be clear, with no Flammable materials.

  2. Glass Safety - Glassware should be handled with care, any breakages should be reported to the teacher.


Diagram:

A clear diagram showing how to set up the experiment. It should follow the rules for creating diagrams seen previously.

For example :


Method:

A clear set of instructions for carrying out the experiment

For example :

  1. Set up apparatus as shown.

  2. Measure 50 ml of water into the beaker using the measuring cylinder.

  3. Measure the starting Temperature of the water.

  4. Light the bunsen burner and start heating the water, recording how long it takes to boil in your table.

  5. Repeat steps 1 - 4, 2 more times.

  6. Repeat steps 1-5 for different volumes of water.


Results:

A clear table showing all measurements taken

For example :

Graph:

A clear graph showing all measurements taken. The graph type will depend on the results gathered in the experiment (see graph skills section)

For example :

Conclusion:

A explanation of what your graph shows, in support of your aim.

For example :

The graph shows that the larger the volume of water used, the longer the time required to make it boil.


Evaulation:

A discussion of how the experiment went. This should be both positive and negative points. The evaluation should also include improvements that could be made.

For example :

This experiment worked well as the graph shows that the results gained closely follow a proportional relationship, with all results being close to the line of best fit.

This experiment could have been improved by using a different starting temperature as the room temperature changed during the experiment, which would affect the results.

This experiment could also have been improved by using a larger range of volumes, to give more data points for the graph. This would make the line of best fit more accurate.



Example Report

Below is an example experimental report for an Electricity experiment investigating Ohm's Law:-

Investigating the Brightness of a Lamp in an Electrical Circuit

Aim:

To investigate how increasing the supply voltage affects the brightness of a lamp.

Hypothesis:

As the supply voltage of the lamp increases the brightness of the lamp will also increase.

Independent Variable:

The supply voltage measured in Volts using a voltmeter.

Dependent Variable:

The brightness of the lamp measured in Lux using a light level meter.

Variables kept constant:

In order to complete a fair and valid experiment the following variables will be kept constant:

  1. Lamp used.

  2. Distance between light level meter and lamp when measuring brightness.

  3. Brightness in classroom.

  4. All apparatus used.

Measurements/Observations to be made:

  1. The supply voltage in Volts using a voltmeter.

  2. The brightness of the lamp in Lux using a light level meter.

  3. The distance between the lamp and Light Meter in meters using a ruler or meter stick.

Resources:

  1. Voltmeter.

  2. 4 x 1.5 DC cells.

  3. Connecting wires.

  4. Switch.

  5. 12V lamp.

  6. Light level meter.

  7. Meter stick or ruler.

Health and Safety:

Working with electrical equipment can be hazardous so care will be taken to avoid contact with water. The lamp may also become hot so care will be taken to avoid touching it. Wires will also be disconnected when the circuit is not in use.

Diagram:

Method:

  1. The circuit was set up as shown in the diagram above.

  2. The voltage of the supply was measured and recorded using a voltmeter.

  3. The brightness of the lamp was recorded using the light meter from a distance of 0.1m.

  4. The above steps were repeated for 2, 3 and 4 cells.

  5. Three readings of brightness for every supply voltage were taken and averaged.

Graph:

Conclusion:

As the supply voltage increases, the brightness of the lamp also increases.

Evaluation:

The investigation was successful as it followed scientific expectations.

If the experiment was to be repeated the following action could be taken:

The experiment could have been carried out in a completely dark room to avoid light from the sun and corridor lights interfering with the readings for brightness. This would give more accurate results but a dark room was not available.