ACTIVATE Balanced Forces

England National Curriculum KS2:

• notice that some forces need contact between 2 objects, but magnetic forces can act at a distance

England National Curriculum KS3

• forces as pushes or pulls, arising from the interaction between 2 objects
• using force arrows in diagrams, adding forces in 1 dimension, balanced and unbalanced forces

• a slinky that appears to defy gravity. How does it work?
• Set the class a challenge – to predict what happens to a slinky spring if you hold it by the top and then let it go. Ask students which option they choose.
• Optional: Demonstrate holding a slinky in class so they can more clearly visualise what is
  happening.
• Show the class what happens by using a video clip. Here is the link to the clip:
• Introduce the engage question – why does the bottom of a slinky defy gravity?
• Presents the objectives for the stage.
  

• The activity presents simple scenarios with questions about the forces that either make an object move, keep it moving and or act against movement. Students answers’ will reveal whether they have the pre-requisite understanding, and whether you need to fill knowledge gaps or correct misconceptions.
• What it covers
• Provide each student with a copy of the ‘check’ task, or project
• Go through the answers with the class and ask students to self-assess. Get them to tick the box
  to show how well they understood the task. Use this to decide who needs to review their
  knowledge. Those that do can complete the Explain stage. Those that don’t can move on to the
  Stretch task

• Fill knowledge gaps? revealed by the pre-assessment
• • What it covers
• Go through the slides, making sure students understand the prior knowledge.
• How do we show forces? Where does the force come from? What happens if the force is larger? What happens if the force is larger?
• Use the outcomes from the questions above to decide if students need more practice.
  Use the slide to direct them to relevant pages in Understanding Science 1 (or replace with links
  to other textbooks).