• Question: Hello again, it said on your profile that you calculate noise to make things quieter. I'm very interested in that. Can you explain it.

    Asked by DonaldTrumpEatingCake to Michael on 20 Jun 2016.
    • Photo: Michael Carley

      Michael Carley answered on 20 Jun 2016:

      There is a lot there to explain, but mostly what I do is study how physical systems make noise, so that we can find which is the noisiest part of device and insulate it, or we can redesign it to make it quieter.

      For example, it was worked out in the early 1950s that making a jet slower makes it much quieter. This has led to aircraft engines becoming bigger over time, so that they move the same amount of air (to give the same thrust) slowly and the noise reduction from having a slower jet is greater than the noise increase from having a larger engine.