### 2. Methods

Independent Variables
1. Type of bulb. (incandescent, fluorescent and LED)

Dependent Variable
1. Temperature of the bulb (in degrees celsius) when it is switched on
2. Light intensity the bulb gives off when it is switched on. (in lux)

Constant Variable
1. The distance between the luminosity reader and the luminous part of the lighting system. (1 metre)
2. The distance between the heat reader and the luminous part of the lighting system. (0 metres)
3. Brightness of location before bulb is activated.
4. Type of power source.
5. The type of luminosity reader that we are using for all the lighting system.
6. The voltage of the power source that we are using to light the bulbs. (240 volts)

2.1 - Equipment List
Requirement:
- Dark location with power socket

Equipment list:                   Quantity:
- LED bulb (size E27)            2 (1 extra for precaution)
- Incandescent bulb (size E27)                   2 (1 extra for precaution)
- Fluorescent bulb (size E27)                        2 (1 extra for precaution)
- Extension cord (5-8m)            2 (Precautionary)
- Light bulb socket (size E26)                       1
- Electrical adaptors            1 set (Precautionary)
- Lux meter            1
- Datalogger            1
- Digital thermometer            1

2.2 - Diagram of Experimental Setup

2.3 - Procedures
1. Connect the power source and light bulb socket.
2. Screw the incandescent bulb into the light bulb socket.
3. Activate the power source.
4. Measure the luminosity using the lux meter and datalogger from 1 meter away from the bulb. (in lux)
5. Note down the lux reading on a Numbers table.
6. Measure the temperature of the surface of the bulb after it has been on for 1 minute. (in degrees celsius)
7. Note down the temperature reading on a Numbers table.
8. Exchange the incandescent bulb for the fluorescent bulb and repeat steps 3 through 7.
9. Exchange the fluorescent bulb for the LED bulb and repeat steps 3 through 7.
10. Tabulate data in Numbers table. (see page below)
11. Transfer data to bar charts. (see page below)

2.4 - Risk Assessment and Management
1. As this experiment involves electricity, avoid contact with exposed wires or uncovered components of the circuit.
2. As the experiment involves bulbs that may heat up, avoid contact with any part of the light bulb without safety measures like gloves.
3. As the experiment in done in an unlit location, ensure that there are no potentially hazardous materials left lying around.

2.5 - Data Analysis
1. Tabulate the data using 3 graphs, 1 for each bulb. Rows are for different voltages applied and columns are for luminosity in lux and temperature in degrees celsius. (examples below are using random numbers and do not reflect actual experiment results)
2. From this table, we can find out which bulb emits the most light and least heat with minimum voltage (the aim).

(note: Tables and charts are filled with placeholder data that does not reflect actual results of the experiment. for actual results, see the ‘3. Results’ page)