Summary of Investigation
An investigation was carried out to find out the relationship between the force created in a wire (or solenoid) when current flowed through it and the force from gravity. This was investigated by connecting a solenoid up to a variable power pack and then placing a light ring of either copper or aluminum around the solenoid. When the current flows through the solenoid, a magnetic force created from the solenoid should make the ring 'jump' up or levitate. When carrying out the experiment, the assumption was made that there will be some movement from the ring when current starts flowing through the solenoid and thus a magnetic field will be present. However, the results of the experiment did not back up this assumption in any way. No magnetic force was observed in any of the experiments carried out.
Introduction
Electromagnetism is the study of the relationships between magnetism, and electricity. It was found by Hans Oersted, that when an electric current flows in a wire, the current creates a magnetic force around this wire. It is also known that a solenoid produces a considerably large amount of magnetic force when a current flows through it (diagram 1.1 ). By using a solenoid and some small, light rings of copper and aluminum, it is said that the ring when placed over the solenoid when current is flowing will 'jump' up and sometimes levitate if the force of the magnetic field equals that of the earth's gravitational force.
Aim
The main objective of this experiment is to investigate the relationship between gravitational energy and electric and magnetic energy. This will be achieved by attempting to suspend a light ring of copper and/or aluminum around a solenoid with a current passing through it. The only presumption is that if the ring is unable to be levitated (due to lack of power), there will still be movement and the ring will jump up from the base of the solenoid.
Method
The circuit used first (see diagram 2.1) was made up of a small solenoid. The solenoid was constructed using a small pencil, bound with electrical tape and copper wire wound around it to a length of 13cm. Zinc plated washers were first used in the circuit using a DC voltage. Because DC voltage was being used, the ring was expected to 'jump' only when the circuit was switched on and off.
All voltages on the power supply were used and different resistances were experimented with using the rheostat.
Kirkpatrick, Larry D. and Gerald F. Wheeler. Physics: A World View. Fourth Edition. Harcourt College Publishers: Orlando, Florida, 2001.
Serway, Jewett. Physics for Scientists and Engineers 6th Edition. Pomona: California State Polytechnic University. 2004.
Acoustic levitation takes advantage of the properties of sound to cause solids,and liquids to float. The process can take place in normal or reduced gravity. To understand how acoustic levitation works, you first need to know a little about gravity, air and sound.
it to a 5V power supply as a more convenient way of measure. As the
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The idea is so simple, it seems absurd. A tether is extended from the surface of the earth, and using a
F Another wire, or exact same properties (Nickel Chrome, thickness 34). mm and length 30cm) was placed on top of the previous wire, in the same position, both straight and flat. F. The power was turned on again and the same procedure was repeated. recording current and voltage at three points on the variable. resistor.
-Voltmeter -Variable resistor -Power Supply -Various diameters of wire -Crocodile clips -Metre ruler [ IMAGE] Diagram:.. Secondary Source - (Obtained in A-level PHYSICS by Roger Muncaster). Page 536 - "The 'Page The electrical resistivity of a material is defined by R = L / A Where R = Resistance of some conductor(Î).
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