Investigating Flux Using a Search Coil Flashcards
What equipment is required for this practical?
Large circular coil
Stands
50Hz AC supply
Protractor card
Search coil
How should the coils be positioned in the setup?
The large circular coil should be mounted vertically, and the search coil should be placed at its center with the planes initially parallel.
How should the components be connected?
The circular coil is connected to the AC supply.
The search coil is connected to the oscilloscope.
How is the induced EMF recorded?
The peak-to-peak voltage of the induced AC voltage is read from the oscilloscope.
How is the angle θ between the search coil and the circular coil changed?
The search coil is tilted in 10° increments up to 90°, using a protractor.
How many times should the experiment be repeated?
The experiment should be repeated twice more, and the mean emf value should be recorded for each angle.
What graph should be plotted from the data?
A graph of induced emf (ε) against cos(θ) should be plotted.
What relationship should the graph show?
A straight line through the origin, confirming that ε is proportional to cos(θ).
What equation describes the induced emf in the search coil?
ε = BANωcos(θ)
How can parallax error be minimized when measuring the angle?
Either read the protractor from directly above or use a set square to align it with the search coil.
What principle does this experiment rely on?
Faraday’s Law of Electromagnetic Induction, which states that the induced emf in a coil is proportional to the rate of change of magnetic flux through it.
What is the role of the search coil?
The search coil detects the induced emf from the circular coil’s magnetic field. Its orientation affects the amount of induced emf.
How should the equipment be set up before starting the experiment?
- Mount the large circular coil vertically using a stand.
- Position the search coil at the center of the large coil using another stand.
- Ensure that the planes of both coils are parallel initially.
- Connect the circular coil to the AC supply and the search coil to the oscilloscope.
- Place the protractor card beneath the coils to measure θ.
What are potential sources of error?
Parallax error when reading the protractor.
Inconsistent positioning of the search coil at each angle.
Oscilloscope settings affecting accuracy of voltage readings.
External electromagnetic interference affecting emf readings.
