Coursework: Investigating how the resistance of a thermistor depends on temperature Aim: To find out, if temperature affects the resistance of a thermistor. Diagram Equipment list: o Thermistor o Crocodile leads o Power source o Voltmeter o Ammeter o Beaker-to hold water Method Set up the equipment as shown in the diagram. Check the settings on the equipment are correct. The thermistor should be connected to the circuit with crocodile clips, placed in the water. Attain the correct temperature for the water using a kettle. To take resistance at that temperature: Take the readings from the Voltmeter and the Ammeter and use Ohm’s law to get the resistance by dividing the volts reading by the amps reading, then x 1000 as the reading comes in milliamps.
The experiment should be repeated for a range of temperatures and should be repeated three times for each temperature to gain accurate results. Preliminary results I took these trial results to get some idea of the results that I would get in the real experiment… From the results I can see that I will have to use an ammeter sensitive to currents in milliamps. Also 90 oC is too hot-I can’t use water that hot, similarly the water only cooled to 23 oC, so I can’t record for 20 oC Prediction I predict that, as the temperature increases the resistance will decrease.
This happens to metals as their temperature it’s resistance decreases as the metal atoms vibrate more violently and obstruct the electrons. Thermistors are made of semi-conductors when cold only a few electrons are free to carry current. Heating the semi-conductors gives other electrons enough energy heating up the semi-conductor; reducing its resistance.
The Essay on Water Pollution 16
Water Pollution People keep on throwing trash and industrial wastes into our clean water. If this continues, the quality of our water will deteriorate, and without it everything dies, including us. Water pollution is destroying our world, but fortunately we can count on special treatments for this kind of problem. What is water pollution? "It is the contamination of water by foreign matter such as ...
