Learn about resistors

 Before you begin 

• Use the safety checklist to help you plan and risk assess your activity. There's also more guidance to help you carry out your risk assessment, including examples.
• Make sure all young people and adults involved in the activity know how to take part safely.
• Make sure you’ll have enough adult helpers. You may need some parents and carers to help. 

Planning and setting up this activity

• Prepare some coloured strips to represent each of the colours of resistor band, with enough for a complete set per group.
• Alternatively, use other coloured items, such as pencils, cones or even books to represent the band colours. You can find examples of these colours can be found in the attached reading resistors sheet.

Playing the game

1. Gather everyone together and explain that you’re going to be doing an activity to learn about resistors. You may need to explain what resistors are using the information on this page.
2. Ask everyone to get into small teams.
3. Give each team a copy of the resistor values sheet. Make sure that everyone understands how the numbering system works.
4. Next, give each team a set of coloured stripes to represent the coloured bands on the resistors. Each team member should take one or two colours.
5. An adult or young leader should call out a value that a resistor might have. For example, 470Ω (ohms).
6. The teams should then decide what order and what colour strips the resistor would have. For example 470Ω would be: yellow (4), violet (7), brown (x10). (47x10=470)
7. The team members with the correct colours should step forward and hold the colours in the correct order to match the resistor number called, from left to right.
8. Alternatively, teams could race across the space to show the caller the correct colour combination.
9. Teams get a point for each correct combination they make. They could also get an extra point for being the first team to get the correct combination.
10. Keep playing until you feel that everyone understands the topic and and everyone has had a go.

Comparing components

1. Come together as a group again. Explain that resistors are marked with coloured strips, but other components use different systems. Many simply carry numbers, such as:

• • Capacitors are marked with a number of different letters and numbers to show how much charge the capacitor can store. The amount of charge they can store is measured in farads and microfarads. If there’s room, they sometimes have the voltage rating on too. Capacitors letters and numbers will vary depending on their size and manufacturer, so always make sure you check them carefully before using.
  • Bulbs carry lots of numbers and ratings, including how many V(volts) they can take and how many W(watts) they are.
  • Integrated circuits have a notch and a dot mark. This is to help you count the pins. They start with number 1 at the dot and count anti-clockwise around the chip.
  • Diodes are marked with a band on one end. This is to tell you which end is the cathode (negative) The end without the band is called the anode (positive).

2. As a group, think about why it might be important to know the rating of different components. One reason is that using the wrong components could result in the components breaking or making the circuit unsafe or unstable. Marking components with numbers, symbols or colours means that they can be read easier than if they were written in words. It also makes them international, so you don’t need to be able to read a particular language to understand the colours.