Force
Forces and Motion

# Cardboard force arrows

Classroom Activity for 11-14 14-16

In this activity students use cardboard arrows to build free-body force diagrams for everyday situations.

## Equipment

Each group of students will also need:

• Set of colour safe force arrows printed on card or paper (download below)
• Pen and paper (or mini-whiteboards)
• Blu Tack (optional)

## Procedure

1. Write the following description framework on the board: “The ___________ arrow represents the _______________ force that acts on the ____________ due to the _____________”
2. Show a photo or demonstrate one situation (you could start with a drinks can sitting on a table).
3. For each situation, ask students to work in pairs to:
• Identify the object and draw it by itself
• Use same-sized arrows if two forces are the same size
• Point each arrow in the direction as the force
• Stick the base of each arrow to the place where the force acts (it's okay for their arrows to overlap)
• Use the description framework to discuss what each arrow represents

## Teaching notes

Giving students the flexibility to change their mind creates a safe space for them to develop their understanding. As students build force diagrams, circulate and use questioning to encourage and progress their thinking:

• What force does that arrow represent?
• What causes that force?
• Where does it act?
• This activity can also be a used as an introduction to Newton’s third law. Ask students to draw diagrams of the other object involved in the interaction (e.g. Earth) and use the same colour of arrow for matching force pairs (e.g. green arrows for the gravitational force on both Earth and the football). Using the same description framework for matching force pairs will help students see that if there is a force on object A due to B, there is an equal and opposite force on B due to A.