British Science Week is a UK-wide programme of events and activities, aimed at people of all ages, to celebrate science, technology, engineering and maths.
Full steam ahead for this year’s first day of the British Science Week as local East Midlands students performed a classic steam train experiment on Friday 13th of March at the Great Central Railway.
This experiment was originally performed by a Dutch scientist (Christophorus Henricus Didericus Buys-Ballot) in 1845, and provided the first experimental confirmation of a physics phenomenon called the Doppler Effect. Buys-Ballot placed a group of musicians on a train and asked the driver to rush past him as fast as he could while the musicians played and held a constant note. Listeners on the platform were able to detect a change in pitch of the note (called the Doppler shift) as the train passed them. Measurement of the Doppler shift makes it possible to estimate how fast an object is moving, which is useful for detecting blood flow through arteries, speeding cars, and how fast the universe is expanding!
In this re-enactment of Buys-Ballot’s original experiment, students used electronic recording equipment to measure the frequency of the sound from the train and calculate how fast the train was moving. For comparison, the speed of the train was measured using speed guns provided by Leicestershire County Council. This was great fun and we are in the process of editing the video, which soon will be available on our youtube channel.
Doppler’s theory was later expanded to include light (using Albert Einstein’s theory of Special Relativity) and now provides a vital tool for mapping the motions of stars in the Milky Way. This was explored further in an open lecture later in the week “From inside the body to outer space using the Doppler effect” held at the National Space Centre Planetarium at 7:30 pm on Wednesday 18th of March.
These two events were funded by the Wellcome Trust and Engineering and Physical Sciences Research Council (EPSRC) and were organised by the University of Leicester in collaboration with STEMNET, the University Hospitals of Leicester NHS Trust, the Institute of Physics (IoP), Institute of Physics and Engineering in Medicine (IPEM), Great Central Railway, Leicestershire County Council, British Medical Ultrasound Society, National Space Centre, and British Science Association.