Prediction
I predict that the more coils that are wrapped round the nail, the stronger the magnetism will become. I think it will be affected less by the amount of current passing through the nail.
I predict that the more current that passes through the nail, the more domains will line up in the direction of the current. I do not think there will be enough voltage to make all the domains line up or become, “Saturated”.
List Of Apparatus
Power Pack- I will use a power pack to allow me to control the number of volts going through the nail at any one time, giving me a constant and reliable current as it is being fed from the mains, and not from a battery.
Nail- The nail will be used to have the wire coiled round to create an electromagnet
Non-Magnetic Wire- This wire will be the wire coiled round the nail, the current will flow through this wire, causing the nail to become a magnet.
Crocodile Clips- I will use crocodile clips to connect the insulated wire to the whole circuit. They make my experiment safer, meaning I do not have to hold the joins in wire together, and therefore avoiding an electric shock.
Insulated Wire.- This will be used to connect the nail to the power pack, creating a full circuit for the current to flow through.
What I Will Measure
For each of the tests, I will measure how strong the magnet is by placing a weight on a balance, and see how much the weight decreases when a magnet is placed above the weight.
This will be much more accurate than lifting up paper clips as the magnet may often be able to pick up half the weight of a paper clip.
Method
How I Will carry out Experiment 1.
1.I will start this experiment by connecting, two insulated wires, to the Power Pack. I will then connect to end ends of the insulated wire two crocodile clips and make sure they are on securely.
2.Before connecting the wire to the nail, I will wrap the wire round the nail, leaving open strands of the wire at each end of the nail. After doing this, I will connect the crocodile clips to the wire, and make sure connections are not loose.
3.I can then take a piece of metal, and place it on a balance and record the weight accurately.
4.I will then make sure the volt rating on the power pack is set to zero, and turn the power pack on.
5.I can then turn the power pack rating up to 2 volts, and place the electro magnet over the balance with a piece of metal on, and measure how much the weight decreases with the magnet pulling the metal up.
6.After carrying this out, and recording my results in a chart, I can repeat the process with higher voltages.
How I Will Carry Out Experiment 2
I will carry out experiment 2 in much the same way as I did in experiment 1.
The experiment will be identical up to the end of stage 3. It is at this point I will count the number of coils around the nail, and adjust them to the desire amount, either 5, 10, 15 or 20 coils.
I can then turn the power pack rating up to 2 volts, and place the electro magnet over the balance with a piece of metal on, and measure how much the weight decreases with the magnet pulling the metal up. After doing this, instead of changing the voltage, I will keep the voltage the same, and change the amount of coils. I can then repeat the experiment several times to collect the results I need. To make sure the experiment is safe, I will turn the power pack off each time I am adding more coils, so there is no current flowing through the wire as I am adjusting it.
Factors I Will Change
I will carry out this investigation by doing two experiments, each one having a different variable.
Experiment 1: Changing The Current.
For experiment 1, I will adjust the current from the power pack. This current will be traveling through a nail that has a non-magnetic wire coiled around it. By changing the current, but keeping the coils the same, I will be able to see how much the electromagnet is affect by a change of up to 10V.
To ensure this experiment is safe, I will start recording my result from the lowest voltage and raise the volts as I go along. This will stop any risk of the wire over heating at the start of the experiment. By going up slowly each time, I will be able to monitor the heat of the wire and nail to check that it is safe to raise the voltage higher.
Experiment 2- Changing the Amount Of Coils.
For experiment 2, I will change the number of coils of wire being wrapped around the nail. I will keep the current set at a certain voltage. This would allow me to see how much the electro magnet is affected by the number of coils wrapped round the nail.
I will keep this experiment safe by turning off the power pack each time I add more coils around the nail, this will avoid the hazard of getting at electrical shock. I will make sure the set voltage is not high enough to make enough heat to burn my fingers when I am adjusting the coils.
How many results
I will collect 2 sets of results for each experiment, and take an average for each experiment; this will allow me to cater for problems and strange results I may encounter in one of the two tests.
