Comparing incandescent lamps and LED lamps
The materials required for the science fair project:
- A 60 watt incandescent light bulb
- Socket for the incandescent lamp
- LED bulbs of several wattage ratings (1.5W, 3.0W, 4.5W, 6.0W, 7.5W, 9.0W, 10.5W)
- Socket for the LED bulb
- Electric cables
- 3-pin plugs
- A lux meter
- A ruler
1. For this science fair project, the independent variable is the type of light bulb used – incandescent bulb and LED bulbs. The dependent variable is the brightness of the bulbs. This is determined by measuring the brightness using a lux meter. The constants (control variables) are the distance of the lux meter from the light bulb, the temperature of the room (which will remain at room temperature) and the power rating of the incandescent lamp.
2. Wire the cables and the plug to the incandescent bulb socket and the LED lamp socket. Test the incandescent bulb and the LED bulb before starting this experiment.
3. Place the lux meter 1000mm from the surface of the incandescent lamp. Turn on the incandescent lamp. Measure the luminous intensity indicated in the lux meter. Record the measurement in a table, as shown below.
4. Disconnect the incandescent lamp from the power socket and connect the LED lamp socket. Test the luminous intensity of the 1.5W, 3.0W, 4.5W, 6.0W, 7.5W, 9.0W, and 10.5W LED bulbs by placing the lux meter 1 meter from the surface. Record the measured reading in a table, as shown below.
Risk of electrocution or burns. Be extremely careful when handling electrical equipment and electrical power supplies. This experiment requires adult supervision.