Here’s that Jonathan Sanderson again, with his kids science TV producer’s eye view of the world, with a toast to gravity. Cheers!

People claim that what makes the world go round is money, but of course we all know that it's conservation of angular momentum and, ultimately, gravity. Durr.

Nevertheless, gravity can still sneak up on us and play nasty tricks. 

It does this to me every morning, when in my clumsy breakfast haze I drop my toast and - horror - add another thin layer of marmalade to my carpet.

We all know that dropped toast lands buttered-side down. What's to be done?

What you need:

• Buttered toast
• A table and an old newspaper
• An upstairs window with a clear drop to the ground.

What you do, and what's going on:

1. Drop some buttered toast.
   
   Actually, it's not quite that simple. If you hurl toast in the air, flicking your wrist to make it flip artfully, it'll land butter-side- down precisely half the time. Which doesn't help explain the observed butter/carpet affinity.
   
   To more accurately simulate the breakfast calamity, you need to knock toast off the side of a table. (Put the old carpet saving newspaper down under it though.) Do that, and you'll find that the toast starts to spin as it slides over the edge. Thanks to a remarkable coincidence of the size of slices of toast, the strength of gravity, and the height of tables, it spins between a quarter and three-quarters of a turn before it hits the ground. Result: it comes to rest butter-side down, as expected.
   
   
2. Do this a few times to be sure. I find it works about 17 times out of 20, which is good enough for me.
   
   To make your toast land butter-side-up, you need to buy it enough time in free-fall (ie. before it hits the ground) to spin at least one complete turn.
   
   
3. This is where the upstairs window comes in. Open the window, and place the toast on the windowsill. Now push the toast off the windowsill, just as you pushed it off the table.
   
   It should - fingers crossed - land flat on its back on the ground below, proudly butter-side up. Hah! Take that, gravity! We have you beaten!

Now if only we had breakfast tables that were 4 metres high...

(Note that you do need some height for this to work - 4 metres is about right. If your first-floor window is quite low, you may need to go up another floor. Also, be very, very careful that the toast falls off the windowsill, and not you. You spin more slowly on the way down, and hence are unlikely to land on your feet.)

Wrong Idea: Ian Francis with the last in a long list of things that seemed so plausible and yet, in the end, weren’t.

Our final Wrong Idea has been known to be wrong for centuries, yet often crops up during school science lessons. A fair few adults get it wrong too!

How do we see things? Well, the following are handy: an eye (or two), which ideally should be open. Plus light. Easy. The misconception concerns the direction light travels.

Ancient Greeks made much of the twinkle in ones eyes, supposing that light came out from the eyes and made objects visible when the light rested on them, (much as you reach out to something to feel its texture) This did give the suggestion that your eyes should be able to light the way at night, Superman-style. So, the theory was refined to suggest some sort of interaction between the twinkle of your eye, and light already out there. Not all the ancients got this wrong (the Roman Lucretius was a notable exception) but the majority view was decidedly incorrect.

The Egyptian scientist Alhazen came remarkably close to the modern theory of vision around 1000AD. He imagined little light particles being thrown off by bright objects, which when they entered your eye enabled you to see the object they’d come from.

When explaining vision nowadays, scientists sometimes consider light to be particles (photons) and sometimes electromagnetic waves. But whichever model is used, the light’s direction is always from the object being viewed to the eye. So unless you surgically implant light emitting diodes into your retina, those Superman-style exploits are impossible for the time being.