Micro:bit drop

How can we use household materials to keep our micro:bit safe when we drop it, and can we calculate force on impact using micro:bit acceleration?

Get your micro:bit + battery pack

Protect it the best you can

Equipment

• micro:bit + battery pack
• Packaging materials to build with
• Either a display-shield or laptop to view the acceleration data with later

Learning overview

• Teamwork and collaboration
• Calculating force from acceleration
• Design & Technology

Experiment setup

For this experiment we are logging data whilst the micro:bit is disconnected from the display-shield.

We will make the micro:bit log its acceleration data when its disconnected, then connect the display-shield again later in order to calculate impact force.

It’s important that the design you build keeps the A button pressable and the LEDs visible, because this is how we start logging on the micro:bit.

Logging data in detached mode

When there’s no display-shield connected, you can press A to start logging the sensor indicated by the symbols on the micro:bit LEDs, or press B to go to the next option.

These 3 symbols all represent the accelerometer option. When we’re ready to drop we will press A.

For now, make sure you can see these 3 symbols, if not press B a few times:

Build around your micro:bit to keep it safe

Make sure you can press the A button and see the micro:bit LEDs!

Start logging

When you’re ready to drop press A on the micro:bit, you will see three dots appear. This means the micro:bit is recording:

Drop the micro:bit from 30cm

When you’re ready to drop press A on the micro:bit, you will see three dots appear. This means the micro:bit is recording:

Stop recording after landing

Press A again to stop the recording, the … will turn into a smiley-face

View accelerometer data

Experiment questions

1. What is the equation for force?.
2. What are the two units for force?
3. If an object weighs 20g and has an acceleration on impact of 10mg (0.01g), what is the force on impact?
4. What is the dependent variable in this experiment?
5. What was the highest or lowest acceleration value in your data?
6. Assuming the answer above is your acceleration on impact, and the mass of the micro:bit + battery pack is 80g: what was the impact force?