LDR response to variations in light intensity

Equipment

LDR
Multimeter
Connecting leads
Crocodile clips
Desk lamp
Metre rule
Blu-Tak

Method

1. Connect the LDR to the multimeter using crocodile clips and connecting leads.
2. Set the multimeter to read ohms.
3. Set the LDR up so it is 10 cm from the lamp. Ensure the lamp and the ruler are fixed in place to reduce errors in measuring distance.
4. Switch on the lamp and use the multimeter to record the resistance of the LDR. Switch off the lamp, then back on and repeat the readings. Repeat once more. Take a mean average of the three readings.
5. Increase the distance from the lamp to the LDR by 5 cm and repeat step 3.
6. Repeat step 4 until the LDR is 40 cm from the lamp.

Safety

The bulb being used may get hot.
The bulb is made of glass which may break.