Google’s Employment Applicant’s Hourglass Problem

Ref: March 2012 issue of Wired magazine.

It seems the Google job interview process requires a problem to be solved. I’ll take this hourglass problem, “Using only a four-minute hourglass and a seven-minute hourglass, measure exactly nine minutes.”

Solution Principle: Use one hourglass to measure out a smaller amount of time on the other hourglass. Repeat until you have the correct time periods stored in each hour glass such that when you add their times together by turning the second one up when the first finishes you get the correct total time of nine minutes.

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Flipping Heck It’s A SmartInversion

Introduction

It’s an unusual flying object – this SmartInversion – that propels itself by flipping inside out. Created by engineers at Festo in Esslingen, Germany. It was originally reported in a New Scientist blog in April 2012 which is no longer online. I decided to investigate it further and found it in the Festo archives.

What I’ve Found

At the time it didn’t appear to have a name  so I called it a Flipping Heck as in, “Flipping heck what is it?” Festo did give it a name apparently. It’s called a SmartInversion. I understand it’s filled with helium to keep it afloat so maybe it’s a Flipping Balloon.

Here is a video of the SmartInversion:

Some parts of the video are speeded up. In reality it only moves slowly. Here is a link to Festo’s article.

Should You Worry About Your Bath Overflowing?

Introduction

“Me, worry about my bath overflowing? Its got an overflow pipe.”

“Oh! Has it?”

Why you DO NEED to worry about your bath overflowing?

I know someone who has had a bad experience with a bath overflowing, but it wasn’t their bath overflowing. It was in a flat two floors above. Interestingly the flat in between on the floor immediately below the bath didn’t get wet. How can that happen?

Well lets start with the overflowing bath. The person, whose bath it was, admitted it had overflowed but not very much. I suspect this means that the water did actually run over the rim of the bath. That means it rose above the bath overflow outlet (assuming there was one.)

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Goldfinches Feeding In My Garden

Introduction

I can’t tell you how pleased I am to have goldfinches feeding in my garden regularly now I have erected a nyjer seed feeder. See this one in my feature image.

A friend across the road has goldfinches feeding regularly but I never have. Why? They never had anything to feed on in my garden. So I bought this expensive feeder, which holds fine nyjer seeds, from the RSPB (Royal Society for the Protection of Birds) together with some seed.

Here is a good article about goldfinches feeding on nyjer seed from East Lansing, Michigan, USA.

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