• 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
6. 6
6
7. 7
7
8. 8
8
9. 9
9

# AC Generator

Extracts from this document...

Introduction

AIM

Research, design and build an electric AC generator. Control and record the effects of changing two variables (varying the space between the magnets and the armature, the velocity of relative motion between the coil and the magnets).

HYPOTHESIS

• As we spin the coil relative to the magnets, the coils should created an electric current that lights up our light bulb or makes movement on the galvanometer.
• The more coils we add, the greater the current produced when in action.
• The closer the magnets relative to the armature, the greater the magnetic field on the armature and the greater the current produced when in action.
• The faster the velocity of relative motion between the coil and the magnets, the greater the current produced.

EQUIPMENT

• 2 Magnets (to produce a magnetic field in the coils)
• Insulated copper wire (for the current to flow through)
• Wood block (for the base)
• Metal axel (for the armature to spin on)
• Wood core (cylinder shape to act as the armature)
• 2 thin metal rectangular pieces (act as the brushes)
• 2 metal slip rings (to connect to the brushes)
• Light Bulb (test if its producing current)
• Tape and glue (stick stuff together)
• 2 small wood pieces (to support the axel at either end)
• Electric hand drill (spin the generator)
• Galvanometer (test the current)

METHOD

Middle

RESULTS

 milli Volts (mV) Speed Trial 1 Trial 2 Trial 3 Trial 4 Average Slow 10 12 13 11 11.5 Medium 15 20 18 20 18.25 Fast 31 34 35 33 33.25

CONCLUSION

The hypothesis stated:

• As we spin the coil relative to the magnets, the coils should created an electric current that lights up our light bulb or makes movement on the galvanometer.
• The faster the velocity of relative motion between the coil and the magnets, the greater the current produced.

As we spined the axle, spinning the coil on the armature relative to the magnets, the coils created an electric current that gave readings on the galvanometer. From our results we can conclude that the faster the velocity of relative motion between the coil and the magnets, the greater the current produced. Therefore our results support the hypothesis stated earlier and the hypothesis was true.

MY EXPECTED RESULTS

• As we spin the coil relative to the magnets, the coils should created an electric current that lights up our light bulb or makes movement on the galvanometer.
• The faster the velocity of relative motion between the coil and the magnets, the greater the current produced.

RESEARCHED RESULTS

My researched results were very similar to my expected results, only they were more accurate then mine since the way I tested my variables weren’t that precise.

Conclusion

the roles of the rotor and the stator can be reversed for the output currentbrushes do not wear as fast as in a DC generatorno possibility of creating an electrical short circuit between segments in an alternator because the slip rings are already continuousmost commercial generators are AC generatorsbetter suited to high current demands
• has losses through electromagnetic radiation or magnetic induction.
• Back emf opposes supplied emf.
• Emits EMR, so wires need insulation and shielding.
• Frequency must be sent to consumers at 50Hz. This has to be maintained and monitored.
• AC has a “skin-effect”; the electrons tend to travel at the edge of the conductor, which makes them slightly less efficient.

DC GENERATORS

 Advantages Disadvantages output can be made smoother by the arranging many coils in a regular pattern around the armatureuse with equipment that needs a steady voltage rather than varying voltage (AC) doesn’t cause losses through electromagnetic radiation or magnetic induction. not good for transmission over long distances without great energy lossesmore complicated to make and maintainlimited usefulness of DC generators to relatively low current applicationslarge currents through the commutator-brush connection increases the likelihood of electric arcs forming as the brush breaks contact with each bar in turn

REFERENCES

Author : Ken J Williams and Janet Pemberton

Publisher : Science Press

Published : 2002

Book : Spotlight Physics HSC

• Jacaranda HSC Physics
• Spotlight HSC Physics
• http://www.phys.unsw.edu.au/~jw/HSCmotors.html
• http://www.amasci.com/amateur/coilgen.html

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. ## Sensing project

5 star(s)

resistor, which has similar resistance to the rotary potentiometer. If the resistance of the rotary potentiometer is 10K? at its highest resistance the angle of the arm will be 3000 (as the arm does not turn a complete 3600). This can be used to show the rough resistance of the rotary potentiometer at different degrees. Angle of Arm (0)

2. ## Objective: To use a search coil and a CRO to investigate the magnetic ...

(V). As the induced e.m.f. ? = -NA dB/dt, the distance from the straight wire decreases with the magnetic field produced by the current-carrying straight wire. Thus, the result agree with the equation , where �0 is the permeability of free space.

1. ## Characteristics of Ohmic and non-Ohmic Conductors.

This could have been avoided by waiting a little while before taking a reading. My metal wires weren't completely ohmic. Even though precautions were taken, by using a small voltage range, the temperature could not have been kept completely constant.

2. ## Objective: l To rectify ...

Waveform of the signal across the resistor displayed on the CRO (waveform E1): 1100-turn inductor without C-core. Waveform of the signal across the resistor displayed on the CRO (waveform E2): Discussion: Error analysis 1. The power supply has some problems.

1. ## eletrical dc motors

Brushes: The brushes typically remain stationary with the motor's housing but ride (or brush) on the rotating commutator. As electrical energy is passed through the brushes and consequently through the armature a torsional force is generated as a reaction between the motor's field and the armature causing the motor's armature to turn.

2. ## silicon project

Glass can be made into a great variety of shapes and is used to make window glass, containers, and insulators, among many other uses. * Abrasives - Silicon carbide is one of the most important abrasives. * Semiconductor - Ultrapure silicon can be doped with arsenic, boron, gallium, or phosphorus

1. ## Choosing a light source

And also looking at my graph above I could now say it does not obey the inverse square proportion law that that is for every, intensity is inversely proportional to square distance, so therefore the intensity decreases by factor d2.

2. ## Investigating the monitoring systems used on modern day large A/C for detection of specific ...

ENGINE VIBRATION GAS-TURBINE AIRCRAFT ENGINE VIBRATION INDICATING SYSTEM The gas-turbine aircraft engine vibration-indicating system features include: engine curls rotation frequency measurement with two independent measuring channels, vibration level measurement with three engine-mounted piezoelectric sensors using digital broadband filters on each vibration sensor or digital monitoring narrow-band filters on curls main

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