Lenz's Law
Practical Activity – Lenz’s Law
Syllabus: 2.7, 2.5, 2.6
Aim – What is the effect of Lenz’s law? How does Lenz’s Law work?
Risk
Rating
Minimisation
1. Skin pinched by magnet
Low
Don’t bring the magnets together and don’t try and hold them apart. Don’t try and separate the rare earth magnets.
2. Hit by swung pole
Low
When holding the pipe, make sure the it is perpendicular to the ground and keep clear of any surrounding people
Procedure –
1. Collect a 1m plastic, metal and another metal with a groove pipe from the front of the room.
2. Collect a Rare Earth Metal from teacher
3. Using the plastic 1m pipe drop the Rare Earth Metal and calculate time taken for it to drop
4. Repeat question 3 at least 3 times to calculate and average
5. From the same height, using the metal ruler measure how long it takes for the same magnet to drop
6. Repeat question 5 at least 3 times for an average
7. Repeat for the metal pipe with a groove.
8. Repeat question 7 at least 3 times for an average
9. Record the results and calculate the average for each of the pipes
10. Pack up the equipment when finished
Results –
Object
Time
Average
Plastic
0.34
0.36
0.42
0.37
Aluminium
3.75
3.61
3.62
3.66
Aluminium w/ groove
2.12
2.26
2.22
2.20
Analysis –
1. What type of metal tube did we use?
The metal we used in the practical was a solid and hollow pipe of aluminium.
2. Why couldn’t we use iron for the tube?
We couldn’t use iron for the pipe as this would have caused the Rare Earth metal to magnetise onto the side of the pipe disenabling the metal to fall through.
3. Name another magnet we could have used?
Copper, zinc, tin etc.
4. What is happening to the magnet and why?
In the plastic tube, the magnet is just dropping as there is only gravity acting on the magnet as there is no attraction between the plastic and the magnet. The time taken for the magnet to fall down the aluminium tube is lower as there is another force
Syllabus: 2.7, 2.5, 2.6
Aim – What is the effect of Lenz’s law? How does Lenz’s Law work?
Risk
Rating
Minimisation
1. Skin pinched by magnet
Low
Don’t bring the magnets together and don’t try and hold them apart. Don’t try and separate the rare earth magnets.
2. Hit by swung pole
Low
When holding the pipe, make sure the it is perpendicular to the ground and keep clear of any surrounding people
Procedure –
1. Collect a 1m plastic, metal and another metal with a groove pipe from the front of the room.
2. Collect a Rare Earth Metal from teacher
3. Using the plastic 1m pipe drop the Rare Earth Metal and calculate time taken for it to drop
4. Repeat question 3 at least 3 times to calculate and average
5. From the same height, using the metal ruler measure how long it takes for the same magnet to drop
6. Repeat question 5 at least 3 times for an average
7. Repeat for the metal pipe with a groove.
8. Repeat question 7 at least 3 times for an average
9. Record the results and calculate the average for each of the pipes
10. Pack up the equipment when finished
Results –
Object
Time
Average
Plastic
0.34
0.36
0.42
0.37
Aluminium
3.75
3.61
3.62
3.66
Aluminium w/ groove
2.12
2.26
2.22
2.20
Analysis –
1. What type of metal tube did we use?
The metal we used in the practical was a solid and hollow pipe of aluminium.
2. Why couldn’t we use iron for the tube?
We couldn’t use iron for the pipe as this would have caused the Rare Earth metal to magnetise onto the side of the pipe disenabling the metal to fall through.
3. Name another magnet we could have used?
Copper, zinc, tin etc.
4. What is happening to the magnet and why?
In the plastic tube, the magnet is just dropping as there is only gravity acting on the magnet as there is no attraction between the plastic and the magnet. The time taken for the magnet to fall down the aluminium tube is lower as there is another force
References: – https://www.google.com.au/search?q=Induction+Cook+tops (1/3/14) http://en.wikipedia.org/wiki/Induction_cooking (1/3/14) http://www.smeg.com.au/how-do-induction-cooktops-work/ (1/3/14) https://www.google.com.au/search?q=Induction+Cook+tops (1/3/14) http://en.wikipedia.org/wiki/Electromagnetic_brake (1/3/04) http://en.wikipedia.org/wiki/Eddy_current_brake (1/3/14)