• Question: what is your favourite experiment?

    Asked by albert to David, Luna, Mark, Melanie, Probash on 17 Mar 2011 in Categories: . This question was also asked by summer8181, microsoftman, beckybeth, amberjane, kathanhal, rckingdom, emnol.
    • Photo: Probash Chowdhury

      Probash Chowdhury answered on 15 Mar 2011:

      One I did at school – the Van der Graf generator. The band rubs inside a dome which causes static electricity. If you hold the dome your hair stands up. If you touch the dome you get a spark and small shock. If you link hands and one end hold the dome, the other end can shock/spark someone else.

      One that we do at work is looking at DNA for damage. We add various dyes and fluorescents and if the DNA is not damaged it glows! A relief for everyone (and looks cool under the microscope).

    • Photo: Luna Munoz

      Luna Munoz answered on 15 Mar 2011:

      My favourite would be a study by Mark Dadds in Australia. He did this study where he brought children who had behaviour problems into the lab with their parents. Some children were cold and uncaring to other people and some were warm and caring. They did a whole bunch of activities together. At the end, he asked the moms to look into their child’s eyes and tell the child that she/he did a great job and that she loved him/her. The children who were more cold did not look into their mom’s eyes even when the mom tried to make eye contact. The children who were more warm did look into their mom’s eyes.

      What was really cool is that they repeated this but with dads. The dads of the children who were cold and uncaring also avoided eye contact during this part of the study. The dads of the children who were warm did make eye contact with their child. Eye contact is one way in which we connect with people and really come to understand what they are feeling. It may be that cold, uncaring, and hurtful children never learn about other people’s emotions because they avoid looking at people’s eyes. Maybe they get it from dad…but that’s not certain.

    • Photo: David Pyle

      David Pyle answered on 15 Mar 2011:

      Hi Albert – being a geologist, I don’t really do lab experiments. I’m always on the lookout, though, for ‘analogue experiments’ using non-geological materials to give a quick peek into how natural systems might behave. Here are two favourites:

      For the sheer fun of it, it would have to be the ‘mentos and coke’ experiment. I think that it works with any sugar-coated sweet in a fizzy drink, and it’s a great example of how the formation and growth of bubbles in a gas-saturated (or supersaturated) liquid can drive a very vigorous eruption. It’s a pretty good simulation of some sorts of volcanic activity!

      A second, which I haven’t tried, shows how fluids can behave differently when they are deformed at different rates. This is the ‘cornflour monster’ experiment. The cornflour-water mix is ‘non-Newtonian’, so it behaves more like a solid at some frequencies, and more like a liquid at others, and the result is quite a surprise. Many natural (geological) materials are also non-Newtonian. One example is the Earth’s hot interior. This is not molten, but creeps slowly (at low deformation rates) and cracks like a solid at high deformation rates.

    • Photo: Melanie Stefan

      Melanie Stefan answered on 17 Mar 2011:

      In the history of science, maybe the Miller–Urey experiment, which showed that the molecules essential to life could form by themselves under the conditions present on early earth.

Comments