INVESTIGATION+OF+LDR+AND+THERMISTOR

Back to HOME > IGCSE PHYSICS > ELECTRICITY > ENERGY AND PD = INVESTIGATION OF LDR AND THERMISTOR = Connect a series circuit containing the component you are investigating; a multimeter set as a sensitive ammeter; a power supply (do not overload the component).

For the **thermistor**, put it in a plastic bag and measure the currents it passes when immersed in: Plot a graph of current against temperature and with the two fixed points and (assuming the relationship is linear), use it to estimate room temperature. For the **photoresistor** (LDR), in a darkened room, place it at different distances from a strong light source and measure the current it passes. Plot a graph of I versus d. You could also try plotting I versus 1/(d squared).
 * melting ice (lower fixed point)
 * steam from boiling water (upper fixed point)
 * the room