A metal detector consists of a battery providing an alternating current to a transmitter coil and a receiver coil connected to a loudspeaker. Using Faraday's Law of Induction explain how a metal detector works. (5 marks)
The alternating current flows through the transmitted coil and produces a magnetic field around the coil. (1 mark) When the detector passes over a magnetic object, the magnetic field passes through the object. (1 mark) This creates a current around the object. (1 mark) This current induces another magnetic field opposing that of the transmitter coil, due to Lenz's Law. (1 mark) This magnetic field passes through the reciever coil, and as a result makes an electric current flow through the reciever coil and up to the loudspeaker. (1 mark)
MH
Related Physics A Level answers
All answers ▸Describe and explain the photoelectric effect in terms of photons interacting with the surface of a metal.
Define a "Vector Quantity" and list 2 examples.
Describe energy transformations in a oscillating pendulum, which undergoes simple harmonic motion. How this implies the velocity at critical (lowest and highest) points?
What is the photoelectric effect?