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Guide and features
Guide and features
Science, Technology, Engineering and Mathematics
Featured Early Years Foundation Stage; US Kindergarten
Featured UK Key Stage 1&2; US Grades 1-4
Featured UK Key Stage 3-5; US Grades 5-12
Featured UK Key Stage 1, US Grade 1 & 2
Featured UK Key Stage 2; US Grade 3 & 4
Featured UK Key Stages 3 & 4; US Grade 5-10
Featured UK Key Stage 4 & 5; US Grade 11 & 12
Making Maths: Make a Pendulum
Stage: 2 and 3
Galileo, a famous inventor who lived about 400 years ago, came up with an idea similar to this for making a time measuring instrument. His idea came from watching a lamp swinging back and forth.
You will need:
Weights (any objects which you can tie to the string)
A piece of wood about $1.5$m long
What to do:
Tie a weight onto the end of the piece of string.
Make a loop at the other end of the string.
Screw the hook into the piece of wood and balance the wood between the backs of two chairs.
Put the loop of string over the hook.
You have now made a pendulum and can begin to experiment to make a minute timer from it.
Start the weight swinging and time how long it takes to make $20$ swings. Use a stopwatch for this.
Find a way to make the pendulum swing $20$ times in $20$ seconds.
Experiment with different size weights.
Try different lengths of string.
Can you turn your pendulum into an accurate minute timer?
This activity features in our
December 2008 Advent Calendar
Meet the team
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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