Radio 2 and blanching

[Andy Hamilton]

I was just listening to Radio 2 early whilst blanching my runner beans ready to freeze them. With no watch I wondered how I could time 2 mins. I emailed Mark Radcliff and asked him to play a song that was 2 mins long.

He instead declared that he would tell me 2 mins into the next song which he did. Strange what they do read out on the radio! Perhaps next time you need to time something you could email whatever radio station you listen to.

[Shirley]

rofl - I hope you said you were Andy from www.selfsufficientish.com and got a plug for the forthcoming book at the same time

[Muddypause]

That's pretty cool, Andy.

But look, next time you need to time something, and don't have a clock, remember that the period of a pendulum is given by the formula

T = 2πSqrt(L/g)

where L is the length of the pendulum string, and g given by G(M/R^2), is about 9.8 M/s^2 (at sea level, anyway).

Rearranging, this gives us

L = g(T/2π)^2

which will let us work out how long the string of the pendulum needs to be if we have a period of, say, 2 seconds (1 second per swing), thus:

L = 9.8(2/2π)^2 = 0.992m

That's rather neat, isn't it? A pendulum with a length of 1 meter will have a period of almost exactly two seconds, which is 1 second per swing. This is confirmed by my experiment of hanging a small spud from a drawing pin in the ceiling - at 1m from ceiling to base of spud, it swung precisely 120 times in 2 minutes.

Interesting to note that it doesn't matter how heavy the potato is, nor how big a swing it does - it only depends upon the length of the string.

[Andy Hamilton]

Hmm yes cheers for that muddy, actually although baffled a little by the maths I gave that a go and substituted the potato with my morning banana. It really works!

[Millymollymandy]

Don't you even have an alarm clock in your house?

To time 2 minutes is easy, you just count out the seconds!

[Shirley]

You've got a clock on the computer too - but would probably take 2 mins to set a reminder lol

[ina]

Perhaps next time you need to time something you could email whatever radio station you listen to.

We'll change "Just a minute" on radio 4 to "Just two minutes"...