Investigating Resistance in Thermistors & LDRs Flashcards

All 3 cards in this deck

What are the steps to investigate how the resistance of a thermistor varies with temperature?
e.g. water from 20 °C to 80 °C

1. Put the thermistor and a thermometer in a beaker of water, with an ammeter in series and a voltmeter across the thermistor.
2. At each temperature (e.g. every 10 °C) record $V$ and $I$ and calculate $R = V/I$.
3. Plot resistance against temperature — the curve falls as temperature rises.

Why is the water stirred when investigating a thermistor's resistance in a water bath?

So the temperature is the same throughout, and the thermometer reading matches the thermistor's temperature.

True or false? Repeating the readings at each temperature or light level lets you check the repeatability of the results.

True. Repeats also let you spot and ignore anomalous results before taking a mean.