A lecture about an experiment

A lecture about an experiment

Listen to the lecture about a science experiment to practise and improve your listening skills.

Do the preparation task first. Then listen to the audio and do the exercises.


In today's lecture we're going to be talking about experiments, and I thought it might be interesting for you all to learn about the world's oldest continuously running laboratory experiment that is still going today. In fact, it holds the Guinness World Record for being the longest-running experiment. This experiment began in 1927 and has been going ever since.

It's called the 'pitch drop' experiment and it was created by Professor Thomas Parnell at the University of Queensland, Australia. Parnell was the university's first physics professor, and he wanted to show in this experiment that everyday materials, such as pitch, can have quite surprising properties.

You see, when pitch is at room temperature, it feels solid. You can easily break it with a hammer. However, it isn't in fact solid. At room temperature, pitch is many billions of times more viscous than water, but it's actually fluid.

In 1927, Professor Parnell took a sample of pitch. He heated it and poured it into a glass funnel. He allowed the pitch to cool and settle – for three years. He then turned the funnel upside down and cut the top off it.

Since then, the pitch has slowly dropped out of the funnel. How slowly? Well, the first drop took eight years to fall. It took another forty years for another five drops to fall. Today it's been almost 90 years since the experiment started. Only nine drops have fallen from the funnel. The last drop fell in April 2014 and the next one is expected to fall in the 2020s.

The experiment has a tragic story associated with it. Professor Parnell died without seeing a pitch drop. His replacement, Professor John Mainstone, became responsible for the pitch drop experiment from 1961. He held the job for 52 years, and missed seeing the drop fall three times – by a day in 1977, by just five minutes in 1988 and finally in 2000, when the webcam that was recording the experiment suffered a power outage for 20 minutes, during which time the pitch dropped.

The pitch drop experiment is something we can all participate in now. There's a live web stream that allows anyone to watch the glass funnel and wait for the fateful moment. A similar experiment to the Queensland pitch drop was set up in Dublin, and the video of the moment the pitch actually dropped went viral on the internet. It's interesting to see how a very slow event can spread news so quickly.

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Submitted by J1927n on Mon, 26/02/2024 - 20:14


I pitifully do not know about any other famous experiment. I do know about regular experiments that I learned in the school or the most famous that you always hear, but no different from them.

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Submitted by alessandro.it on Sat, 17/02/2024 - 17:54


At university, I learnt about several interesting experiments made in physics, but the "pitch drop" is really very curious to know.
The first experiment I did was when I was at the primary school. It was a botanic experiment. I put some beans on the bottom of a glass for bear, I make them wet and then I covered them with some cotton. After some days, I saw the roots coming out of the beans: a new plant was growing! That made me very happy.

Submitted by amroelwan.com on Mon, 04/12/2023 - 18:59


My favourite is Isaac newton's law of motion and forces experiments that made him one of the greats of science

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Submitted by Yasin Danyal on Tue, 03/10/2023 - 21:23


Yes, I can certainly tell you about some famous experiments from various fields of science and psychology. Here are a few notable ones:
-Stanford Prison Experiment (1971)
-Little Albert Experiment (1920)
-Double-Slit Experiment (1801)
-Pavlov's Dogs (1890s)
-Hawthorne Studies (1920s-1930s)
-Skinner's Box (Operant Conditioning Chamber)
-Asch Conformity Experiments (1950s)
These experiments have had a lasting impact on their respective fields and have often raised ethical and philosophical questions about human behavior, perception, and ethics in research.

Submitted by marcialopes on Wed, 06/09/2023 - 21:11


Honestly, I don't remember any famous experiment like the pitch experiment. However, I find it intriguing and haven't heard of it before. After completing my current task, I plan to look for the live stream out of curiosity.

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Submitted by Ramiro Solana on Tue, 08/08/2023 - 22:49


I remember an experiment carried out by Galileo during the Renaissance. He dropped two balls of the same size but different weights on an inclined floor and saw that they both ran at the same speed past each other. He then concluded that in free fall, the acceleration due to gravity is not affected by the weight of objects.

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Submitted by Anwarow on Wed, 26/07/2023 - 14:09


actually i can't remember a big experiment like the pitch drop. However a hollandies guy i follow on the youtube he made most push ups in 1 minute with helicopter and he got reward from gennies record.That's the only experiment i think its worth to write.

Submitted by Sliang on Wed, 26/04/2023 - 04:43


Off the top of my head, I can't think of any experiments as famous as the pitch drop experiment. However, I do remember learning about the famous story of Isaac Newton observing an apple fall from a tree, which led him to discover the concept of gravity. This is a great example of how simple observations can lead to groundbreaking scientific discoveries.

Submitted by Alayo on Wed, 15/03/2023 - 19:39


I really like to read a article or watch a video about experiments. Also, i interested in chemical when i got to high school.Now, ı have been working as a R&D engineer and we have been doing a lot of experiments to improve our products to have better one. For example , when ı worked at FORD Otosan, ı was responsible of the development tests of the Gen 2 and electricity engines for the trucks. We have tried to find a better solutions to reduce C02 emission to have a better world in the future without climate change. We can fix our world together