Travellers guide to physics – how to have a quiet night’s sleep

The quietest hotel in the world?

by Wendy Sadler

I’m heading out of the UK for a few days as I’ve been invited to share some science made simple experiences with the European Physical Society conference in Belgrade. They’ve asked me to talk about how we can engage more non-specialists with physics. In preparation I’ve been looking around me on the way to Heathrow to consider just how physics makes all our lives easier – especially when travelling.

Heathrow airport is loud! CC-BY Mariordo

Last night I stayed at Jury’s Inn, Heathrow, in one of the quietest hotel rooms I have ever slept in. I was about about 100 metres from the runway of one of the world’s busiest airports. It was astoundingly quiet. Being a bit of a sound geek I wanted to understand a bit more about how they do it.

If you’re trying to soundproof a room, windows are your enemy. It’s where most of the sound would normally get in. All materials have something called an STC rating (Sound transmission class) and it tells you what percentage of sound can get through. Sound is made of vibrations, and depending on the material, more or less of these vibrations can get through to you. Walls generally have an STC rating of  30-50 but a normal window will be about 27 which means you could hear normal speech through it very easily, and loud plane engines very very easily!

Sound is a physical movement of air or material, therefore it needs something to travel in. Different materials block different frequencies, or parts, of the sound. The best solution to blocking sound is to use a mix of different materials. With windows you can use a mix of different glass thicknesses, covered in a plastic laminate and then separated by an air gap (or even a vacuum – in space, no-one can hear you scream!).

Soundproof window CC-BY-SA

Soundproof window CC-BY-SA Dumbonyc

An air gap of 6 inches can decrease sound levels by up to 10dB. That might not sound much but the dB scale isn’t like a straight line graph. A decrease of 10dB (for example) means a sounds is at least half as loud.

My windows at the hotel had 3 panes of glass, which may have been laminated, and there was an air gap of about 6 inches. Weirdly if you use the same glass and have the glass equally spaced out, you don’t stop any more sound. The equally spaced glass can resonate and make the space more effective at transferring sounds!

Thanks to physicists understanding how sound works, and how materials can block it, I had a good quiet nights sleep and also a foam mattress at the hotel helped me a lot. And by the way, after some research I did online I found out that they are the best option when it comes to improve your resting at night. You can have one like I did last black friday deals mattress. I’m not going to even mention the physics of number-plate recognition at the airport car park, the X-Ray security machines at the airport, and even the internet which let me book a cheap flight…all thanks to physics!

If you want to find out more about sound, music and resonance from a science viewpoint, you should check out our ‘Music to your ears‘ show, or the hugely successful ‘Bionic Ear‘ show which we wrote on behalf of Deafness Research UK.

I’m off to board my plane….

_________________________________________________________________________

Free water worksheets

Sign up for our newsletter

Sign up to our newsletter for all the news on where we are performing, our new shows, the best of our blog, fun activities and our latest special offers.

We are giving away a series of 7 free water worksheets for KS2 and KS3 or simply to have a go at with the kids in your life, when you sign up to our newsletter.

These worksheets contain fun demonstrations, facts and tips on topics such as pressure, surface tension and water saving. Just pop your details in below and the sheets will be sent straight to your inbox.


 

We have a wide variety of engineering shows for primary, secondary and family audiences.

We also work in partnership with Tomorrow’s Engineers to inspire the next generation of engineers!

_________________________________________________________________________

 

sms group shot with props smallWe are science made simple, a social enterprise who perform science, maths and engineering shows to school, festival and public audiences.
You can find out more about what we do, check out our exciting range of shows, or sign up to our newsletter to keep updated on what we are up to!
Tagged with: , , , ,
Posted in Engineering, Exploring Science, Physics