Electricity and Magnetism

Series and Parallel Circuits

Electricity moves through a circuit. A circuit is a path that electricity can follow. For electricity to work, the path must be closed, which means complete with no breaks.

In this lesson, you will learn about two common kinds of circuits: series circuits and parallel circuits. You will compare how electricity moves in each one and what happens to bulbs or other devices in the circuit.

Understanding these two kinds of circuits helps us explain how flashlights, room lights, and many other tools work.

Parts of a Simple Circuit

Most simple circuits have a few main parts:

• Power source: gives energy, like a battery
• Wires: carry electricity through the circuit
• Load: something that uses electricity, like a light bulb or motor
• Switch: opens or closes the circuit

If the switch is closed, electricity can move. If the switch is open, the path is broken and electricity stops.

What Is a Series Circuit?

A series circuit has only one path for electricity to follow. The electricity must move through each part, one after another, in a line.

You can think of a series circuit like a single hallway. Everyone must walk through the same hallway to get through the building. There are no other routes.

In a series circuit:

• There is only one path for the current
• All parts are connected in a row
• If one part stops working, the whole circuit stops
• Adding more bulbs usually makes each bulb dimmer

Why do bulbs get dimmer in a series circuit?

The battery gives a certain amount of push to the electricity. This push is called voltage. In a series circuit, that push is shared by all the bulbs.

If one bulb gets all the push, it can shine brightly. If two or three bulbs must share the push, each one gets less, so they are usually dimmer.

What Is a Parallel Circuit?

A parallel circuit has more than one path for electricity to follow. The electricity can split and travel along different branches.

You can think of a parallel circuit like roads that branch into two or more streets. Cars can take different routes to reach the end.

In a parallel circuit:

• There are multiple paths for the current
• Each branch can have its own bulb or device
• If one bulb stops working, the others can still stay on
• Bulbs are often brighter than in a series circuit with the same battery

Why can bulbs stay bright in a parallel circuit?

In a parallel circuit, each branch gets energy from the battery. Instead of sharing one single path, each bulb has its own path. Because of this, each bulb can often shine as if it is connected more directly to the battery.

Voltage and Current

Two important ideas help us compare circuits:

• Voltage: the push that moves electric charges
• Current: the flow of electric charges through a circuit

You do not need to memorize hard formulas, but it helps to know what these words mean.

We can write current in a simple way like this:

$$\text{current} = \text{flow of electric charges}$$

And voltage like this:

$$\text{voltage} = \text{push that moves charges}$$

How Voltage Behaves in Series Circuits

In a series circuit, the battery's voltage is shared by the parts in the circuit.

For example, if a battery gives 6 volts and there are 2 matching bulbs in series, the voltage may be shared about equally:

$$6 \text{ volts} \div 2 = 3 \text{ volts for each bulb}$$

This helps explain why the bulbs can be dimmer.

How Current Behaves in Series Circuits

In a series circuit, the same current flows through every part because there is only one path.

Since electricity cannot choose another route, the flow through bulb 1 is the same as the flow through bulb 2.

How Voltage Behaves in Parallel Circuits

In a parallel circuit, each branch gets the battery's voltage.

For example, if the battery is 6 volts, one bulb on one branch can get 6 volts, and another bulb on another branch can also get 6 volts.

That is one reason bulbs in parallel circuits are often bright.

How Current Behaves in Parallel Circuits

In a parallel circuit, the current can split between the branches.

If two branches are the same, the current may split evenly. If one branch is different, the split may not be equal. The important idea is that the electricity has more than one path.

Comparing Series and Parallel Circuits

• Series circuit: one path
• Parallel circuit: more than one path
• Series circuit: if one bulb goes out, all go out
• Parallel circuit: if one bulb goes out, others can stay on
• Series circuit: bulbs often get dimmer when more are added
• Parallel circuit: bulbs usually stay brighter
• Series circuit: current is the same through all parts
• Parallel circuit: current splits among branches
• Series circuit: voltage is shared
• Parallel circuit: each branch gets the battery's voltage

Worked Example 1: One Path or Many?

A circuit has a battery, a switch, and 2 bulbs connected one after another in a single loop. What kind of circuit is it?

Step 1: Ask how many paths the electricity can take.

There is only one loop, so there is only one path.

Answer: It is a series circuit.

Worked Example 2: What Happens If a Bulb Breaks?

Two bulbs are connected in series. One bulb burns out. What happens to the other bulb?

Step 1: Remember that a series circuit has only one path.

Step 2: If one bulb burns out, the path is broken.

Answer: The other bulb goes out too because the circuit is no longer closed.

Worked Example 3: Sharing Voltage in Series

A 9-volt battery is connected to 3 matching bulbs in a series circuit. About how much voltage does each bulb get?

Step 1: In a series circuit, the voltage is shared.

Step 2: Divide the battery voltage by the number of matching bulbs.

$$9 \div 3 = 3$$

Answer: Each bulb gets about 3 volts.

Worked Example 4: Current in a Parallel Circuit

A battery is connected to 2 equal branches in a parallel circuit. Each branch has 1 bulb. What happens to the current?

Step 1: In a parallel circuit, electricity has more than one path.

Step 2: The current splits between the branches.

Answer: The current flows through both branches, and with equal branches it may split about evenly.

Real-Life Examples

• Flashlights often use simple series circuits
• Lights in a house are usually connected in parallel so one light can turn off without turning off all the others
• Holiday lights can help show the difference: older sets often acted more like series circuits, while many newer sets are made so one bulb going out does not turn off the whole string

How to Tell the Difference

When you look at a circuit, ask these questions:

1. Is there only one path for electricity?
2. Or does the circuit split into branches?
3. If one part breaks, would everything stop or only one branch?

If there is one path, it is series. If there are branches, it is parallel.

Common Mistakes to Avoid

• Do not think that all circuits have only one path. Some have branches.
• Do not forget that a broken bulb in a series circuit stops the whole circuit.
• Do not mix up voltage and current. Voltage is the push; current is the flow.
• Do not assume current stays the same in parallel branches. It can split.

Quick Check

Try answering these on your own:

1. A circuit has 3 branches. Is it series or parallel?
2. In which kind of circuit does one broken bulb usually turn off all bulbs?
3. In which kind of circuit is voltage shared among bulbs?
4. In which kind of circuit does current split?

Answers:

1. Parallel
2. Series
3. Series
4. Parallel

Summary

A series circuit has one path for electricity. The current stays the same through all parts, and the voltage is shared. If one part breaks, the whole circuit stops.

A parallel circuit has more than one path. Each branch gets the battery's voltage, and the current can split between branches. If one branch stops working, the other branches can still work.

When you compare circuits, always look for the number of paths. That is the easiest way to tell whether a circuit is series or parallel.

Electromagnetism Fundamentals

Have you ever wondered how a crane can lift heavy metal in a junkyard or how a doorbell makes a sound? Many of these tools use electromagnetism. Electromagnetism happens when electricity and magnetism work together.

In this lesson, you will learn an important idea: when electric current flows through a wire, it creates a magnetic field around the wire. This means electricity can make magnetism happen.

What is electric current?

Electric current is the movement of tiny charged particles through a wire. In a simple circuit, current travels from a battery through wires and back to the battery.

You can think of current like water moving through a hose. If the water flows, it can do work. In the same way, when electric current flows through a wire, it can light a bulb, run a motor, or create a magnetic field.

What is a magnetic field?

A magnetic field is the area around a magnet where magnetic forces can act. A refrigerator magnet has a magnetic field around it. Even though you cannot see the field, it can pull on some metal objects.

Here is the big idea of this lesson: a wire with electric current also has a magnetic field around it. So, a wire carrying current acts a little bit like a magnet.

How does a wire become magnetic?

When no current is flowing, a plain wire does not act like an electromagnet. But when the circuit is closed and current moves through the wire, a magnetic field forms around the wire.

This magnetic field circles around the wire. The field is strongest when the current is flowing. If the current stops, the magnetic field disappears.

Electromagnet

An electromagnet is a magnet made by electric current. It usually has a wire wrapped around a piece of iron, like an iron nail. When current flows through the coiled wire, the iron becomes magnetic.

Electromagnets are useful because they can be turned on and off. A regular magnet is always magnetic, but an electromagnet only works when current is flowing.

Why wrap the wire in coils?

A single straight wire makes a magnetic field, but it is usually weak. If the wire is wrapped into coils, the magnetic field becomes stronger.

Each loop of wire adds to the magnetic effect. More loops usually mean a stronger electromagnet. This is why many electromagnets use tightly wrapped coils.

What can make an electromagnet stronger?

There are a few simple ways to make an electromagnet stronger:

• Add more coils of wire. More loops create a stronger magnetic field.
• Use a stronger battery or more batteries, if it is safe. More current can create a stronger magnetic field.
• Wrap the wire around iron. An iron nail or iron core helps strengthen the magnet.

What can make it weaker?

• Fewer coils of wire
• Less current flowing through the wire
• No iron core inside the coil
• An open circuit, where current cannot flow

A simple way to picture it

Imagine the wire is the center of a set of invisible circles. When current flows, magnetic field lines form around the wire in circles. We cannot usually see these lines, but we can notice their effects.

For example, a compass needle placed near a wire with current can move. That happens because the wire's magnetic field pushes or pulls on the compass needle.

Everyday uses of electromagnetism

Electromagnetism is part of many things you may see or use:

• Scrapyard cranes lift heavy metal objects with large electromagnets.
• Doorbells use electromagnets to make a striker hit a bell.
• Speakers use electromagnetism to create sound.
• Electric motors use magnetic forces to create motion.

Worked Example 1: Is there a magnetic field?

A student connects a battery, a wire, and a bulb in a complete circuit. The bulb lights up. Does the wire have a magnetic field around it?

Step 1: Ask if current is flowing. The bulb is lit, so current must be moving through the wire.

Step 2: Remember the rule: a current-carrying wire creates a magnetic field.

Answer: Yes. Since current is flowing, there is a magnetic field around the wire.

Worked Example 2: Open circuit or closed circuit?

A battery is connected to a wire wrapped around a nail, but one part of the wire is not attached. The circuit is open. Will the nail act like a magnet?

Step 1: In an open circuit, current cannot flow.

Step 2: No current means no magnetic field from the wire.

Step 3: Without that magnetic field, the nail will not become an electromagnet.

Answer: No. The nail will not act like a magnet because the circuit is open.

Worked Example 3: Which electromagnet is stronger?

Look at two electromagnets:

• Electromagnet A: 5 coils of wire around an iron nail
• Electromagnet B: 15 coils of wire around an iron nail

Both use the same battery. Which one is likely stronger?

Step 1: Both have iron nails, so both can become electromagnets.

Step 2: Compare the number of coils. Electromagnet B has more coils.

Step 3: More coils usually make a stronger magnetic field.

Answer: Electromagnet B is likely stronger.

Worked Example 4: Counting paper clips

An electromagnet with 10 coils picks up 3 paper clips. A student changes it to 20 coils using the same battery and same iron nail. What will probably happen?

Step 1: The only big change is the number of coils.

Step 2: More coils usually make the electromagnet stronger.

Step 3: A stronger electromagnet can usually pick up more metal objects.

Answer: It will probably pick up more than 3 paper clips.

Important ideas to remember

• Electric current is the flow of charged particles through a wire.
• When current flows through a wire, it creates a magnetic field around the wire.
• If the current stops, the magnetic field goes away.
• A coiled wire can make a stronger magnetic field than a straight wire.
• A wire wrapped around iron can form an electromagnet.
• More coils and more current usually make an electromagnet stronger.

A tiny math connection

If one electromagnet has 5 coils and another has 15 coils, you can compare them by subtraction:

$$15 - 5 = 10$$

The second electromagnet has 10 more coils, so it is likely stronger if everything else stays the same.

If a magnet picks up 2 paper clips, and a stronger one picks up 5 paper clips, the increase is:

$$5 - 2 = 3$$

That means it picked up 3 more paper clips.

Quick check for understanding

1. What happens around a wire when electric current flows through it?
2. Can an open circuit make an electromagnet work?
3. Why do coils make an electromagnet stronger?
4. What might happen if you add more coils to a wire around an iron nail?

Brief summary

Electromagnetism is the connection between electricity and magnetism. When electric current flows through a wire, it creates a magnetic field around the wire. If the wire is wrapped into coils, especially around iron, it can become an electromagnet. Electromagnets are useful because they can be turned on and off, and they can be made stronger by adding more coils or increasing the current.

Electromagnets and Solenoids

Magnets can pull on some metals, like iron and steel. You may have seen a refrigerator magnet or a magnet in a toy. But did you know that electricity can also make a magnet? This kind of magnet is called an electromagnet.

In this lesson, you will learn what electromagnets and solenoids are, how they work, and how to make them stronger. You will also learn why they are called temporary magnets.

What is an electromagnet?

An electromagnet is a magnet made by using electric current. Electric current is the flow of electricity through a wire. When electricity moves through a wire, it creates a magnetic field around the wire.

If the electricity stops, the magnet becomes weak or stops acting like a magnet. That is why an electromagnet is called a temporary magnet. It works only while current is flowing.

What is a solenoid?

A solenoid is a long wire wrapped into many loops, like a spring shape. When electric current flows through the loops, the magnetic fields from each loop work together.

This makes one stronger magnetic field through the center of the coil. A solenoid is often used to build an electromagnet.

How does a simple electromagnet work?

A simple electromagnet usually has these parts:

• a battery for energy
• a wire for the electric current
• a coil of wire, called a solenoid
• a metal core, often an iron nail

When the wire is wrapped around an iron nail and connected to a battery, current flows through the coil. The coil creates a magnetic field. The iron nail inside the coil helps make the magnetic field much stronger.

The iron nail becomes magnetized while the current is on. It can then pick up small metal objects, such as paper clips.

Why does the coil shape matter?

If you use a straight wire, it makes a magnetic field. But the field is not very strong in one place. When the wire is wrapped into a coil, the magnetic fields from each loop add together.

This means the coil shape helps focus the magnetic field. More loops close together can make the magnet stronger.

How can you make an electromagnet stronger?

You can change several things to make an electromagnet stronger. Scientists and engineers test these changes to find the best design.

1. Increase the number of wire loops
   More loops usually make a stronger magnetic field. If you wrap the wire around the nail more times, the electromagnet can often pick up more paper clips.
2. Make the coil loops closer together
   This is called coil density. If the loops are packed closely, the magnetic field is stronger through the center of the solenoid.
3. Use a better core material
   An iron core usually works better than no core at all. Iron helps the magnetic field become stronger.
4. Increase the electric current
   A stronger current can make a stronger electromagnet. For example, adding another battery in the correct way may increase the current. This should only be done safely with adult help.

Important safety note: Wires and batteries can get warm. Never leave a wire connected to a battery for too long. Always follow teacher or adult directions during experiments.

Core material: why iron helps

The core is the material inside the coil. A core can be made of iron, steel, or another material. Soft iron is often a very good choice for an electromagnet because it becomes magnetic easily when current flows.

If there is no core, the solenoid still makes a magnetic field. But it is usually weaker than a solenoid with an iron core.

Temporary magnets vs. permanent magnets

A permanent magnet, like a refrigerator magnet, stays magnetic on its own. An electromagnet needs electric current to stay magnetic.

This is useful because electromagnets can be turned on and off. They can also be made stronger or weaker by changing the design.

Why are electromagnets useful?

Electromagnets are useful because people can control them. They are used in many machines and tools.

• junkyard cranes that lift metal cars
• doorbells and buzzers
• speakers and headphones
• some electric locks
• machines in factories

In all of these, the magnet can be switched on when needed and off when not needed.

What happens if you change the direction of the current?

A solenoid has two ends, like a bar magnet. One end acts like a north pole and the other end acts like a south pole.

If the direction of the current changes, the poles switch ends. The electromagnet is still a magnet, but its direction changes.

Worked Example 1: Choosing the stronger electromagnet

Two students make electromagnets.

• Electromagnet A has 10 loops of wire around an iron nail.
• Electromagnet B has 30 loops of wire around the same kind of iron nail and uses the same battery.

Question: Which electromagnet will probably be stronger?

Step 1: Compare the number of loops.

Electromagnet B has more loops: 30 loops instead of 10 loops.

Step 2: Use the rule.

More loops usually make the magnetic field stronger.

Answer: Electromagnet B will probably be stronger.

Worked Example 2: Picking the best core

A student tests three cores inside the same coil:

• a plastic straw
• a wooden stick
• an iron nail

Question: Which core will probably make the strongest electromagnet?

Step 1: Think about which material helps magnetic fields most.

Iron is a metal that can become strongly magnetized.

Step 2: Compare the choices.

Plastic and wood do not help much. Iron helps a lot more.

Answer: The iron nail will probably make the strongest electromagnet.

Worked Example 3: Improving a design

Mia makes an electromagnet with a battery, a wire, and an iron nail. It picks up 2 paper clips. She wants it to pick up more.

Question: What are two changes Mia could try?

Step 1: Think of ways to strengthen an electromagnet.

• add more loops
• wrap loops closer together
• use an iron core
• increase the current safely

Step 2: Pick two changes.

Mia already has an iron nail, so two good changes are:

• wrap the wire around the nail more times
• make the loops closer together

Answer: She can add more loops and pack the loops more closely.

Worked Example 4: Comparing coil density

Two solenoids each have 20 loops of wire and the same battery. In Solenoid X, the loops are spread out. In Solenoid Y, the loops are packed closely together.

Question: Which solenoid will likely make the stronger electromagnet?

Step 1: Notice what is the same.

Both have 20 loops and the same battery.

Step 2: Notice what is different.

Solenoid Y has greater coil density because the loops are closer together.

Step 3: Use the rule.

Closer loops usually make the magnetic field stronger.

Answer: Solenoid Y will likely make the stronger electromagnet.

A simple way to test electromagnets

Scientists test one change at a time. This helps them know which change caused the result.

For example, you could test:

• 10 loops, then 20 loops, then 30 loops
• use the same battery each time
• use the same iron nail each time
• count how many paper clips each electromagnet picks up

This is a fair test because only one thing changes: the number of loops.

You could even record your data in a table.

Example:

Loops and paper clips picked up:

• 10 loops  2 paper clips
• 20 loops  4 paper clips
• 30 loops  6 paper clips

This pattern shows that more loops can make the electromagnet stronger.

A tiny bit of math

If one electromagnet picks up 3 paper clips and a stronger one picks up 7 paper clips, the stronger one picks up:

$$7 - 3 = 4$$

So it picks up 4 more paper clips.

If you add loops in groups of 5, starting with 10 loops, then the next amounts could be:

$$10, 15, 20, 25$$

This helps you plan a careful experiment.

Main ideas to remember

• An electromagnet is a magnet made with electric current.
• A solenoid is a coil of wire.
• When current flows through a solenoid, it creates a magnetic field.
• An iron core can make the electromagnet stronger.
• More loops, closer loops, and more current can increase strength.
• Electromagnets are temporary magnets because they work only while current flows.
• Electromagnets are useful because they can be turned on and off.

Brief Summary

Electromagnets are magnets made by electricity. A solenoid is a coil of wire that helps make the magnetic field stronger, especially when it is wrapped around an iron core. You can design a stronger electromagnet by adding more loops, packing the loops closer together, using iron as the core, and increasing current safely.

Electromagnetism and Induction is the idea that electricity and magnetism are connected. When electricity moves through a wire, it can make a magnetic force. Also, when a magnet moves near a wire, it can help make electricity. These ideas help many useful things work, like doorbells, fans, motors, and generators.

In this lesson, you will learn what an electromagnet is, how to make one stronger, and how induction helps create electricity. You will also see how these ideas are used in electric motors and generators.

First, let’s remember what a magnet does. A magnet can pull on some kinds of metal, like iron. Magnets have two ends called poles. One end is the north pole, and the other is the south pole. Opposite poles pull together, and matching poles push apart.

Electricity is the movement of tiny bits of energy through a path, such as a wire. When electricity flows in a wire, it creates a magnetic field around the wire. A magnetic field is the area around a magnet or electric wire where magnetic force can act.

This is where electromagnetism begins. Electromagnetism means magnetism made by electricity. If electricity flows through a wire, the wire becomes a little like a magnet.

One straight wire makes only a weak magnetic effect. But if the wire is wrapped into a coil, the magnetic effect becomes stronger. If the coil is wrapped around an iron nail, the nail can become a strong temporary magnet. This is called an electromagnet.

An electromagnet is a magnet that works only when electricity is flowing. When the electricity is on, the electromagnet can pull paper clips or other small iron objects. When the electricity is off, the magnetism mostly goes away.

Parts of a simple electromagnet often include:

• a battery
• a wire
• an iron nail or iron core

The battery gives energy to push electricity through the wire. The wire carries the electricity. The iron nail helps make the magnetic force stronger.

How to build a simple electromagnet:

1. Take a piece of wire.
2. Wrap it around an iron nail many times.
3. Leave two wire ends open.
4. Connect the wire ends to a battery.
5. Bring the nail near paper clips to see if it picks them up.

Important safety note: A real battery and wire can get warm if left connected too long. Activities like this should always be done with an adult or teacher helping.

What makes an electromagnet stronger? There are a few simple ways:

• More wire loops: More wraps around the nail make a stronger magnetic field.
• A stronger battery: More electricity can make the magnet stronger.
• An iron core: Using an iron nail inside the coil helps a lot.

If you compare two electromagnets, the one with more loops often picks up more paper clips. The one with fewer loops usually picks up fewer paper clips.

We can show the idea with a simple number sentence. If one magnet picks up 3 paper clips and another picks up 6, then:

$$6 > 3$$

This means the second electromagnet is stronger in that test.

Worked Example 1: Comparing two electromagnets

Electromagnet A picks up 2 paper clips. Electromagnet B picks up 5 paper clips. Which one is stronger?

Step 1: Compare the numbers 2 and 5.

Step 2: Since 5 is greater than 2, Electromagnet B is stronger.

We can write:

$$5 > 2$$

Answer: Electromagnet B is stronger because it picked up more paper clips.

Now let’s learn about induction. Induction happens when a moving magnet helps make electricity in a wire. The key idea is movement. If the magnet moves near the wire, electricity can begin to flow.

You can think of it this way: electricity can make magnetism, and moving magnetism can help make electricity. That is why electricity and magnetism are a team.

If you move a magnet in and out of a coil of wire, the moving magnet can push energy into the wire. This can make a tiny electric current. A current is the flow of electricity.

If the magnet does not move, there is little or no new current made by induction. Movement matters. Faster movement can make a bigger effect, and more wire loops can also help.

Worked Example 2: What causes induction?

A student puts a magnet next to a coil of wire and holds it still. Then the student moves the magnet back and forth through the coil. When is electricity more likely to be made?

Step 1: Holding the magnet still does not change much.

Step 2: Moving the magnet changes the magnetic field near the wire.

Answer: Electricity is more likely to be made when the magnet moves back and forth through the coil.

Generators use induction. A generator is a machine that makes electricity by motion. In a simple generator, a magnet moves near wire coils, or wire coils move near a magnet. This motion helps create electric current.

Generators are used in many places. For example, wind can spin big blades, and that spinning motion helps a generator make electricity. Flowing water can also spin parts of a generator.

Motors do the opposite job. A motor uses electricity to create motion. Inside a motor, electricity flows through wires and makes magnetic forces. These forces cause parts to spin.

So, remember this important difference:

• Motor: electricity in, motion out
• Generator: motion in, electricity out

Worked Example 3: Motor or generator?

A toy fan uses a battery. The battery sends electricity into the fan, and the blades spin. Is the fan using a motor or a generator?

Step 1: Electricity is going in.

Step 2: Motion is coming out because the blades spin.

Answer: The fan is using a motor.

Now imagine a hand-crank flashlight. When you turn the handle, parts inside move and make electricity for the light. In that case, motion goes in and electricity comes out. That is a generator.

Worked Example 4: Observing a hand-crank flashlight

A student turns the handle of a flashlight 8 times. The turning motion helps make electricity for the bulb. Is this induction? Is it acting more like a motor or a generator?

Step 1: The student gives motion by turning the handle.

Step 2: The flashlight makes electricity.

Step 3: Motion helping make electricity is induction.

Answer: Yes, this is induction, and it acts like a generator.

Let’s put the big ideas together.

• Electricity flowing in a wire can make a magnetic field.
• A coil of wire can make the magnetic effect stronger.
• An iron nail inside the coil helps make an electromagnet.
• More loops can make an electromagnet stronger.
• A moving magnet near a wire can help make electricity. This is induction.
• Motors use electricity to make motion.
• Generators use motion to make electricity.

Quick Check

1. What is an electromagnet?
2. What are two ways to make an electromagnet stronger?
3. What must happen for induction to work?
4. Which machine makes motion from electricity: a motor or a generator?
5. Which machine makes electricity from motion: a motor or a generator?

Sample Quick Check Answers

1. An electromagnet is a magnet made by electricity flowing through a wire.
2. You can add more loops of wire or use an iron nail in the middle.
3. A magnet or coil must move so the magnetic field changes.
4. A motor makes motion from electricity.
5. A generator makes electricity from motion.

Summary

Electromagnetism shows that electricity and magnetism are connected. When electricity flows through a wire, it can create magnetism. When a magnet moves near a wire, it can help create electricity by induction.

Electromagnets are useful because they can be turned on and off. Motors and generators use these same ideas in everyday life. By understanding electromagnets and induction, you can see how science helps power many tools and machines around you.