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### Course: Middle school physics>Unit 2

Lesson 7: Electromagnetism

# Electromagnetism

Review your understanding of electromagnetism in this free article aligned to NGSS standards.

## Key points:

• When electric charges move, they create magnetic fields in the space around them.
• Electric charges moving through a wire create electric current.
• Because electric currents are made up of moving charges, they create magnetic fields. An electromagnet is a coil of wires that becomes a magnet when electric current runs through it.
• Electromagnets only work when the electric current is turned on.
• Increasing the electric current or increasing the number of wire loops increases the strength of the electromagnet.
• Changing the magnetic field around a coil of wire (by moving a magnet nearby) can create electric current in the wire.
• Increasing the speed of the moving magnet, using a stronger magnet, or increasing the number of wire loops produces more electric current.
• Moving the coil of wire around a magnet will also create electric current.

## Want to join the conversation?

• What can electromagnets be used for?
• Generators, motors, transformers, and a lot more.
• why do we need electromagnets to help us with technology?
• Electromagnetism is an extremely important field. You use forms of electromagnetism everyday, from turning on a lamp, turning on a microwave, doing laundry. Motors in these devices are created with electric currents which are created from your power company using electromagnetism to produce electricity which travels through power lines into your home's power system, powering your house. So, by reading this, typing on your computer, you are using electromagnetism for your technology.
• what if we never had eletromagnets
• (written by AI) electromagnets have a profound impact on our daily lives and are integral to numerous technological advancements. Without them, our ability to generate electricity, power devices, communicate, conduct medical diagnoses, and pursue scientific research would be severely limited, but humans could still live
• Why does everything have energy
• Everything in the universe has energy because energy is a fundamental property of matter and particles. At the most basic level, all matter is made up of tiny particles called atoms, and these atoms contain energy. Fun fact, Energy is conserved, meaning it cannot be created or destroyed, but it can be converted from one form to another.
• how doses the magnetic force transfor from the particals to the wire?
• the particles are part of the wire basically what it's made out of. So the wire and the particles are both charged.
• what can electromnets be use for
• They are sometimes used in cranes.
• This is really interesting but also quite difficult to wrap your head around. Will we further delve into this topic in High School and College Physics?
• Probably
• I thing I should copy that study work.
• what happens if we loose magnetic charge
• (written by AI): Demagnetization of a magnet: If a magnet loses its magnetism, it would no longer exhibit the attractive or repulsive properties associated with magnets. It would become an ordinary piece of material without magnetic properties. This could affect its ability to interact with other magnets or magnetic materials.

Loss of magnetism in a magnetic material: If a magnetic material, such as iron or steel, loses its magnetism, it would no longer be attracted to magnets or exhibit its own magnetic properties. This could impact its usefulness in applications where magnetism is desired, such as in electromagnets or magnetic storage devices.

Loss of Earth's magnetic field: The Earth itself has a magnetic field that extends around the planet, creating the North and South magnetic poles. If the Earth were to lose its magnetic field, it would have significant consequences. The magnetic field plays a crucial role in protecting the Earth from solar radiation and cosmic particles, which would otherwise reach the surface and potentially have harmful effects on organisms and electronic systems.

It's worth noting that the Earth's magnetic field has fluctuated throughout history and even undergone reversals, where the North and South magnetic poles switch places. However, the complete loss of Earth's magnetic field would have profound effects on various aspects of our planet and its inhabitants.