Why can’t the microwaves fit through the holes? Visualising e-m waves

Many microwave ovens have a gauze in their window, to reflect the microwaves and keep them inside the oven. Someone once asked me “How come the microwaves can’t fit through the holes?” It’s a brilliant question. Which we are not going to answer. If you want to, you can look up ‘how diffraction depends on […]

Orbits, gravity and the atmosphere

“Things float in space because there’s no gravity above the atmosphere, right?” I was thinking about this common misconception, and I thought I’d share it (I just did!) and then explain ‘the truth’. And then it occurred to me that this misconception is so interesting that exploring how/why it is so tenacious and persuasive in […]

Has your action had an equal and opposite reaction?

In our post on anthropomorphism, we discussed benefits and pitfalls of ascribing human motivation to subatomic particles. There is a related but different phenomenon, which can occur when popular culture appropriates a scientific idea. It often happens when science uses an everyday word for a technical concept – people may then be forgiven for generalising […]

Earth’s atmosphere

This wasn’t supposed to be a post on Earth’s atmosphere. I was trying to write about a common but underappreciated misconception about orbits, gravity and the atmosphere (post to follow!). But I kept writing phrases like “above the atmosphere”. And it became clear I was being dishonest. I mean I know that there is no […]