• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5

# An investigation into how the strength of an electromagnet is affected by varying the current

Extracts from this document...

Introduction

An investigation into how the strength of an electromagnet is affected by varying the current

Introduction

I am investigating whether, and if so, how an electromagnet is affected by varying the current. An electromagnet is a magnet created by winding a wire around a soft iron c-core and running a current through the wire. Current is measured in Amperes (A).

Variables available

Voltage

Current

·N0 of coils around the c-core

Size of the c-cores (thickness/length)

Type/size of the wire coiled around the c-core

I chose to use current as my variable. I decided this because I have access to accurate equipment to measure the current, when I change it. The other available variables will be kept constant throughout the experiments.

Aim

I aim to find how varying the current in an electrical circuit affects the strength of an electromagnet.

Background Scientific Knowledge

My c-cores that I will be using will be ferromagnetic, meaning that it quickly becomes demagnetised when the current is switched off and that it is very good at increasing the strength of the magnetic field produced by the current in the wire. To become magnetic in the first place, the electrons in the c-core (the one with the wires around)

Middle

1)I will set up the apparatus as shown in the diagram below.

2)Set the current at the right amount of amps.

3)Use newtonmeter to pull c-core from magnetised c-core (slowly).

4)Record the force (N) and minus the weight of the c-core.

5)Repeat 2-4.

Equipment list

1 Power Pack

1 Ammeter

2 Soft Iron Cores in a C-shape

Wires

1 Voltmeter

1 Variable Resistor

Newtonmeters (0-1,0-10,0-50N)

I am going to test how many Newtons it takes to pull the metal away from the electromagnet, with different currents. I will have to subtract the force due to gravity that the C-core has. This is because I will be pulling the c-core, from the electromagnet, vertically. It will give me the true reading of how many Newtons it actually took to pull the objects apart.

Fair tests

I will make it a fair test by keeping everything the same, apart from my variable (current). To change the current, I will need to change the resistance, which, in turn, will change the voltage (V=IR), so I will need to include a voltmeter into the circuit to make sure that the voltage can be monitored and will be easy to correct. So, the things that I am keeping constant are:

Conclusion

If I had extended time, I could investigate the experiments further, and get more accurate results. I would like to have done more experiments with a higher current. This would mean that I could investigate the saturation theory, and whether beyond a certain point, it does not matter how much you increase the current, the electromagnet will not get stronger. Also, I could mathematically prove my theory about the current directly affecting the electromagnets strength, due to its increase in power. I could measure the gradients of the graph to find the exact increase in strength between each measurement. It would also be useful and interesting to see whether

the heat of the variable resistor affected the results. My anomalous result could have been due to the variable resistor being cold, during the first experiment, when all of the equipment was cold.

I would also like some extra time to do some proper research into the findings of the first people to test this investigation. It would also be interesting and useful to discover what they found.

Acknowledgements

Encarta '98

The Cambridge Encyclopedia

Amperes theory web page for engineers

This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics section.

## Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Related AS and A Level Electrical & Thermal Physics essays

1. ## The aim of my investigation is to determine the specific heat capacity of aluminium.

Due to this drop in temperature more lagging was added to the block and heating source for the remaining experiments.

2. ## A2 Viscosity investigation

Radius2 (m2) Distance Travelled(m) Time taken (s) Average Velocity (ms-1) 1 2 3 899x10 203 x10 60x10 7.72 8.14 8.96 71.8x10 +or-4.8x10 634x10 101 x10 60 x10 11.14 12.01 16.73 45.1x10 +or-9.2x10 316x10 25.4 x10 60 x10 24.75 23.97 26.47 23.9x10 +or-1.2x10 199x10 9.80 x10 60 x10 55.09 55.67 56.07

1. ## resistivity if a nichrome wire

To overcome this problem, the wire could have been stretched out evenly using a plier, to even out the thickness of the wire. Fluctuations in the readings The readings on the voltmeter and the ammeter kept flickering (was not stable).

2. ## The varying of the resistance of nichrome wire depending on its length

to control the volume in a CD player. A filament lamp is a type of light bulb which has a coil of wire inside known as the filament. When current passes through, the wire heats up and thus produces light.

1. ## AimI am trying to find out how the current changes with the area of ...

* I will handle all electrical equipment with dry hands to prevent electrical shocks. * Tuck stools in to prevent no-one falling in the lab. * Put all bags under the table to prevent no-one falling in the lab. * Never run in the lab.

2. ## In this experiment I intend to find out what affect the amount of turns ...

the same meaning that the coils length varies with the number that there are. I have chosen to use the latter method because I think the changing the size of the turns would have a greater negative effect than changing the length of the coil.

1. ## Find out whether a longer wire or a shorter wire will have more or ...

Current is measured in (A) Amperes or Amps. (V) Voltage is the difference in electrical potential between two points in a circuit. It's the push or pressure behind current flow and through a circuit, and is measured in volts (V). (R) Resistance determines how much current will flow through a component.

2. ## Energy Efficiency Experiments

* Transmission of the electrical energy over the distribution grid between the power station and the consumer results in a distribution loss of 10% mainly due to the resistance of the electrical cables. * Further energy is lost due to the energy conversion efficiency of the end user's appliance.

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to