Skip to main content

Why Cats Land On Their Feet – Mark Levi ***

When I saw this book and its subtitle ‘and 76 other physical paradoxes and puzzles’ I thought ‘Great, a nice relaxing evening.’ There’s a certain class of popular science book which piles in a collection of rather interesting factoids with a spot of background, the literary equivalent of watching a soap opera on TV. You sit back, disengage the brain, and chill out. Only, when I switched on this soap opera (as it were) the opening credits said ‘Written and Directed by Ingmar Bergman.’
This is anything but a collection of entertaining science facts. Rather it is a set of challenging physics puzzles, some of which I suspect the average university lecturer would get wrong on the first attempt.
Broadly the 77 items fall into two camps, the delightful and the tedious. The delightful ones present you with a comprehensible (and often apparently straightforward) scenario and ask you either to predict what happens next, or to explain why it happens. These I found very enjoyable. I was taken back to my primary school, where there was a science event where you had to guess what would happen if, for example, you blew between two ping-pong balls suspended near each other by threads. Then you would try it and see what really happened. These puzzles are very much the mental equivalent.
Let me give you two quick examples. The first has two astronauts, fixed to either end of a weightless space capsule. One pushes a helium balloon towards the other. What happens to the capsule itself? Does it move, and if so in what direction? The second involves bashing the bottom of a wine bottle against a wall. (It’s recommended you put a book between the book and the wall, and wear protective clothing.) With repeated thumps, the cork will gradually move out of the bottle. But why?
The tedious examples either involved mathematical working (which for me is the point at which something goes from being a puzzle to being homework) or involved complex setups it was difficult to relate to or have any interest in. Sadly, there were considerably more of these than the delightful problems.
One other issue was that the explanations were often too summary to give a real understanding of what was going on. The book would have been better with fewer problems and a bit more detail. Take the example of one of the delightful puzzles. How does a child (or anyone else) manage to get a swing moving when they are sitting on it? The key to the explanation is that the movements you make on the swing amount to doing work and ‘the energy mismatch goes into increasing the amplitude of the oscillations.’ But this doesn’t really help. I want to know why it increase those oscillations. Why the energy goes to that as opposed to, say, making the seat bounce up and down. There isn’t enough detail, and what there is can be quite impenetrable unless you know the physics anyway.
So – a great idea, with some entertaining examples, but nowhere near as good as it could have been.

Paperback 

Kindle 
Using these links earns us commission at no cost to you
Review by Brian Clegg

Comments

Popular posts from this blog

Mathematics with Love – Mary Stopes-Roe *****

Admittedly it’s early days (this review is written in January), but this, for me, is the surprise hit of the year so far! I approached this book with trepidation, but found it absolutely delightful. It is described on the cover as the “courtship correspondence of Barnes Wallis, inventor of the bouncing bomb”, and contains a series of letters between Wallis and his cousin and eventual wife Molly Bloxham, along with some useful annotation by their daughter, Mary. The courtship itself is not without difficulties, as Wallis was 18 years older than the 17-year-old Molly at the start of the correspondence, and her father, not surprisingly, wasn’t too pleased about the interest of such an elderly suitor, but that isn’t the only reason the letters are interesting – it’s also because of maths, and Wallis’s position in the UK as the engineering hero of the Second World War. (Incidentally, it seemed very strange to see letters addressed to “Barnes” – I had always assumed Barnes Wallis was a ...

Why Nobody Understands Quantum Physics - Frank Verstraete and Céline Broeckaert **

It's with a heavy heart that I have to say that I could not get on with this book. The structure is all over the place, while the content veers from childish remarks to unexplained jargon. Frank Versraete is a highly regarded physicist and knows what he’s talking about - but unfortunately, physics professors are not always the best people to explain physics to a general audience and, possibly contributed to by this being a translation, I thought this book simply doesn’t work. A small issue is that there are few historical inaccuracies, but that’s often the case when scientists write history of science, and that’s not the main part of the book so I would have overlooked it. As an example, we are told that Newton's apple story originated with Voltaire. Yet Newton himself mentioned the apple story to William Stukeley in 1726. He may have made it up - but he certainly originated it, not Voltaire. We are also told that ‘Galileo discovered the counterintuitive law behind a swinging o...

On Time - Jim Al-Khalili *****

By a small margin Jim Al-Khalili's The World According to Physics is my favourite of his books, both because the 'three pillars' concept at its heart works so well - but also because it's short. On Time is somewhat heavier, but thankfully not a wrist-buster. It might seem at first sight odd that a book on a subset of physics is considerably longer than one covering the whole thing, but time is one of those subjects that inevitably involves considerable complexities and needs depth. As Al-Khalili establishes, it's hard to think of any other scientific concept where our perception of it - what he refers to as manifest time or psychological time - is so different from the view from physics. Some physicists go so far as to suggest that time doesn't exist at all. In the book, Al-Khalili sets out (to my mind quite successfully) both to explain why they think this is the case, but also why it's not the best interpretation of time. I'd certainly note that I...