Joule's Law
JOULE’S LAW
Introduction and research question
In this experiment, we were going to investigate the resistance R of an immersion heater. We had to make our own heater, and measure the resistance using a multimeter. Then we had to measure the current I, using an ammeter and a voltmeter. And at last, we had to determine the power P of the immersion heater. This experiment would require to make a table with the data collection, a graph, and a few calculations using Joule’s and Ohms law.
Our research question is: How can we prove Joule’s law?
Experiment procedure
First build an immersion heater with a cable joints and wires. The heater consists of an approximately 25 cm twisted kanthal wire. Wrap the wire around a pencil for a slinky effect. Tighten the screws to assure that the wires are fastened. To determine the power P of the immersion heater, fill up half of a plastic cup with regular tap water (must be able to cover the wire), and heat it with your immersion heater. By measuring the temperature of water as a function of time, and draw a graph, you can calculate the power P. The heater is lowered into the water and is connected to an AC power supply (alternating current). At the same time using an ammeter and voltmeter, measure the current I through the resistor and the pad. Measure for 5 – 10 min. Make a table and a graph.
Apparatus
Data collection
Our first investigation was to measure the resistance of the immersion heater using a multimeter.
The resistance was measured to:
R = 0,73 Ω
After, we had to determine the power P of the immersion heater by using water heating. The method was explained in the experiment procedure.
First we measured the current I through the resistor using an ammeter and a voltmeter.
The measured values are:
I = 4,8 A
p.d. = 3,5 V
The results of our experiment are displayed in the table below.
Mass of the water: 175,47 g (amount of water) – 6,3 g (plastic cup) = 169,17 g Time (min.) | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
Introduction and research question
In this experiment, we were going to investigate the resistance R of an immersion heater. We had to make our own heater, and measure the resistance using a multimeter. Then we had to measure the current I, using an ammeter and a voltmeter. And at last, we had to determine the power P of the immersion heater. This experiment would require to make a table with the data collection, a graph, and a few calculations using Joule’s and Ohms law.
Our research question is: How can we prove Joule’s law?
Experiment procedure
First build an immersion heater with a cable joints and wires. The heater consists of an approximately 25 cm twisted kanthal wire. Wrap the wire around a pencil for a slinky effect. Tighten the screws to assure that the wires are fastened. To determine the power P of the immersion heater, fill up half of a plastic cup with regular tap water (must be able to cover the wire), and heat it with your immersion heater. By measuring the temperature of water as a function of time, and draw a graph, you can calculate the power P. The heater is lowered into the water and is connected to an AC power supply (alternating current). At the same time using an ammeter and voltmeter, measure the current I through the resistor and the pad. Measure for 5 – 10 min. Make a table and a graph.
Apparatus
Data collection
Our first investigation was to measure the resistance of the immersion heater using a multimeter.
The resistance was measured to:
R = 0,73 Ω
After, we had to determine the power P of the immersion heater by using water heating. The method was explained in the experiment procedure.
First we measured the current I through the resistor using an ammeter and a voltmeter.
The measured values are:
I = 4,8 A
p.d. = 3,5 V
The results of our experiment are displayed in the table below.
Mass of the water: 175,47 g (amount of water) – 6,3 g (plastic cup) = 169,17 g Time (min.) | 0 | 1 | 2 | 3 | 4 | 5 | 6 |