Using magnetic fields to keep things moving Flashcards
like magnetic poles do what?
repel
how do we make an electromagnet?
wrap insulated wire around an iron core
electro magnets are used where?
- scrapyard cranes
- circuit breakers
- electric bells
- relay
an electronic motor works how?
it has a coil which turns when a current is passed through it.
If the strength of the magnetic field is increased or the current is increased what happens?
the motor effect is increased
in a motor the force is what position compared to the magnetic field or wire?
right angles
what is the process of electromagnetic induction?
the process of creating a potential difference using a magnetic field
when a conductor cuts the line of field
a voltage is induced across the ends of a conductor
what are the three components in a transformer?
Iron core, primary core and secondary core
why do transformers only work across ac?
changing the magnetic field is required to induce the second coil
what two materials can a transformer use?
- iron
- ferrite (switch transformer only)
a switch mode transformer is?
smaller and lighter, it operates at higher frequencies
the higher the grid pd the greater the…
efficiency of transferring electricity
what 4 things do we use physics for in hospitals?
- when blood pressure is measured
- an ECG recording is made
- an endoscope is used
- a scanner is used
