Define the term: Magnet
A material or object that produces a magnetic field
Two like poles will _______ Each other. Two opposite poles will _______ Each other.
Repel, Attract
Earth's magnetic field is the same shape as what?
A regular bar magnet
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What is an electromagnet?
A magnet produced by the electric current moving through a wire.
D/N
Draw a diagram of the magnetic field of a bar magnet.
Define the term: Magnetic Field
Outline the difference between a permanent magnet and an induced magnet.
Permanent magnet - Always produces its own magnetic field.
Induced magnet - Only produces a magnetic field whilst in the magnetic field of another magnet
What is the cause for Earth's Magnetic Field?
Earth’s core has molten iron and nickel which is always spinning.
The spinning core acts like a magnet.
Name 3 uses of electromagnets.
Automatic door locks
Headphones/ Speakers
Scrap yard cranes
Transformers
Motors
Bullet Trains
Name Three Magnetic Metals
Iron, Cobalt, Nickel
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Define the term: Magnetise
To give magnetic properties; make something magnetic
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D/N
The magnetic poles flip every few thousand years, so the Magnetic North pole has not always been at the bottom of the planet.
What are the three ways to increase the strength of an electromagnet?
Increasing current
Increasing the number of turns of the coil
Adding an iron core
What is the cause of all magnetic fields?
Moving electric charges (Electrons)
Define the term: Solenoid
A coil of wire acting as a magnet when carrying electric current
What are the four rules for magnetic field lines?
Field lines flow from North to South
Field lines never cross each other
The closer the lines are to each other, the stronger the magnetic field
Field lines are continuous
Why is the North pole of a Compass attracted to the North Pole of the Earth?
The (geographic) North Pole is actually the Magnetic South Pole.
D/N
Outline two advantages and one disadvantage to using an electromagnet over a regular magnet.
Adv: Can turn it on and off, Can increase/ Decrease strength
Dis: Quite expensive to make/ run
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Describe how to make an electromagnet.
Coil a wire around an Iron core. Plug the wire into a power supply. Turn on the power supply.
D/N
A force which acts on an object without coming physically in contact with it
Describe how to plot the magnetic field pattern of a bar magnet.
Place the magnet on the page, Place a plotting compass at the N - Pole, Draw a dot where the compass is pointing, Move the centre of the compass onto the dot, Repeat until you reach the sound pole, Connect the dots to show the field line, Repeat to have 4-6 field lines.
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What are three reasons Earth's Magnetic Field is important?
Protecting Life
Navigation
Protecting the atmosphere
Explain the trend in the data below:
The higher the number of coils in the wire, the more paperclips the magnet could hold because more coils in the wire increase the strength of the electromagnet.
Define the three types of variables in an experiment.
Independent: The Variable you Change
Dependent: The Variable you Measure
Controlled: The Variables you Keep the Same