Electromagnets

CONCEPTUAL

Science›Forces & Motion|Ages 12—13|ID: mt_2qkn8Lhc8e

Describe the magnetic effect of an electric current (a current-carrying wire produces a magnetic field), and investigate how the strength of an electromagnet depends on current, number of coil turns, and core material

Mastery Evidence

Describes that a current-carrying wire produces a circular magnetic field
Lists three factors that affect electromagnet strength: current size, number of coil turns, and core material
Explains why an electromagnet can be switched on and off, unlike a permanent magnet

Assessment Prompt

“If [child] built an electromagnet using a battery, wire, and iron nail, could they describe two ways to make it pick up more paperclips — and explain why it stops working when the circuit is switched off?”

Curriculum Standards1 alignment

MS-PS2-3Next Generation Science Standards (NGSS) Middle Schoolcodes only

Standard code — full text not included in this dataset.

Prerequisites2

Current, voltage, and what they measure
hardAges 11—12
Magnetic Fields
hardAges 11—12

Show full prerequisite tree

Current, voltage, and what they measure hard
The magnetic effect of a current requires understanding what an electric current is and how it flows
- Circuit vocabulary hard
  Understanding current as charge flow and voltage as energy per charge requires these exact technical terms
- Drawing circuits with proper symbols hard
  Understanding current and voltage as quantities requires the ability to read circuit diagrams with standard symbols, established at KS2
  - Why circuit components behave differently soft
    Understanding component variations supports interpreting and drawing circuit diagrams
    - Circuit vocabulary hard
      Comparing circuit component function requires component vocabulary: bulb, buzzer, switch, resistance
    - More batteries, brighter bulb hard
      Must understand voltage-brightness relationship before comparing component variations
      - How switches work hard
        Must understand switches and circuits before investigating voltage effects
        
        Will the bulb light up? hard
        Must understand complete loops before understanding how switches open/close them
        
        Building a simple circuit hard
        Must build circuits before predicting whether a lamp will light
        
        What uses electricity at home hard
        Must identify electrical appliances before building circuits
      - Circuit vocabulary hard
        Associating brightness with voltage requires 'voltage', 'current', and 'series circuit' vocabulary
      - How energy travels around soft
        Energy transfer concept supports understanding voltage as energy per charge
        
        Light & Seeing in the Dark soft
        Light knowledge supports understanding energy transfer by light
        
        Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
        
        Naming types of energy hard
        Describing energy transfer by sound, light, heat, and electric current requires energy type vocabulary
        
        Building a simple circuit hard
        Must know circuits before understanding energy transfer by electric current
        
        What uses electricity at home hard
        Must identify electrical appliances before building circuits
        
        Vibrations & Sound soft
        Sound knowledge supports understanding energy transfer by sound
        
        Light & Sound Vocabulary hard
        Understanding vibrating materials and sound requires 'vibration' vocabulary
        
        Communication with Light & Sound hard
        Must understand how sound works before designing a communication device using it
        
        Light & Seeing in the Dark hard
        Must understand how light works before designing a communication device using it
        
        Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
  - More batteries, brighter bulb hard
    Must understand circuit behaviour before representing circuits with formal symbols
    - How switches work hard
      Must understand switches and circuits before investigating voltage effects
      - Will the bulb light up? hard
        Must understand complete loops before understanding how switches open/close them
        
        Building a simple circuit hard
        Must build circuits before predicting whether a lamp will light
        
        What uses electricity at home hard
        Must identify electrical appliances before building circuits
    - Circuit vocabulary hard
      Associating brightness with voltage requires 'voltage', 'current', and 'series circuit' vocabulary
    - How energy travels around soft
      Energy transfer concept supports understanding voltage as energy per charge
      - Light & Seeing in the Dark soft
        Light knowledge supports understanding energy transfer by light
        
        Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
      - Naming types of energy hard
        Describing energy transfer by sound, light, heat, and electric current requires energy type vocabulary
      - Building a simple circuit hard
        Must know circuits before understanding energy transfer by electric current
        
        What uses electricity at home hard
        Must identify electrical appliances before building circuits
      - Vibrations & Sound soft
        Sound knowledge supports understanding energy transfer by sound
        
        Light & Sound Vocabulary hard
        Understanding vibrating materials and sound requires 'vibration' vocabulary
        
        Communication with Light & Sound hard
        Must understand how sound works before designing a communication device using it
        
        Light & Seeing in the Dark hard
        Must understand how light works before designing a communication device using it
        
        Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
- More batteries, brighter bulb hard
  KS2 observation that more cells gives brighter bulbs is the empirical foundation for defining voltage as energy per charge
  - How switches work hard
    Must understand switches and circuits before investigating voltage effects
    - Will the bulb light up? hard
      Must understand complete loops before understanding how switches open/close them
      - Building a simple circuit hard
        Must build circuits before predicting whether a lamp will light
        
        What uses electricity at home hard
        Must identify electrical appliances before building circuits
  - Circuit vocabulary hard
    Associating brightness with voltage requires 'voltage', 'current', and 'series circuit' vocabulary
  - How energy travels around soft
    Energy transfer concept supports understanding voltage as energy per charge
    - Light & Seeing in the Dark soft
      Light knowledge supports understanding energy transfer by light
      - Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
    - Naming types of energy hard
      Describing energy transfer by sound, light, heat, and electric current requires energy type vocabulary
    - Building a simple circuit hard
      Must know circuits before understanding energy transfer by electric current
      - What uses electricity at home hard
        Must identify electrical appliances before building circuits
    - Vibrations & Sound soft
      Sound knowledge supports understanding energy transfer by sound
      - Light & Sound Vocabulary hard
        Understanding vibrating materials and sound requires 'vibration' vocabulary
      - Communication with Light & Sound hard
        Must understand how sound works before designing a communication device using it
        
        Light & Seeing in the Dark hard
        Must understand how light works before designing a communication device using it
        
        Light & Sound Vocabulary hard
        Observing that objects need illumination to be seen requires the 'light source' vocabulary
Magnetic Fields hard
Electromagnetism requires prior understanding of magnetic field lines and field direction — established in the magnetic fields topic
- Magnetic Poles hard
  KS3 magnetic field lines and Earth's magnetism extends KS2 magnetic poles, attraction and repulsion
  - Magnetic Materials hard
    Must observe magnets attract/repel before formalising pole rules
    - Contact & Non-Contact Forces hard
      Must know about non-contact forces before investigating magnetic attraction/repulsion
      - Forces Vocabulary hard
        Distinguishing contact from non-contact forces requires these exact terms
      - Drawing Force Diagrams soft
        Distinguishing contact and non-contact forces is clarified by drawing force diagrams showing where arrows originate
      - Friction & Surfaces hard
        Must experience contact forces like friction before distinguishing contact vs non-contact forces
        
        Pushes & Pulls hard
        Must understand forces change motion before comparing movement on different surfaces
        
        Drawing Force Diagrams soft
        Understanding pushes and pulls as forces is supported by the arrow representation of magnitude and direction
        
        Forces Vocabulary hard
        Comparing how things move on different surfaces requires friction vocabulary

Unlocks1

Motors & the Motor Effect
hardAges 13—14