Alex

Harris If you accelerate downwards faster than the rate of natural free fall, you will experience what is known as a negative g-force. As you accelerate, the liquid in your body – your blood – moves slower than the solid parts of your body due to the inertia of the blood, often resulting in a feeling of weightlessness. Examples would be travelling in a car accelerating over the crest of a hill or riding on a rollercoaster that accelerates downwards. Negative g-forces can result in the blood gathering in your head and giving everything a slight red tinge – something pilots often experience in high-speed dives.

Did you know?

The first rollercoaster in the US opened in 1884

WHY ARE MOTHS ATTRACTED TO LIGHT?

@fizzysgirl

The theory that moths fly towards light because they think it’s the Moon has never been proven. The latest thinking is that because moths have such sensitive eyesight, lights blind and disorientate them. When a light comes into their field of vision they see it as a donut. When they change course to fly towards the light they are actually trying to fly to the dark spot in the middle. Another theory is that moths aren’t attracted to light – it’s simply that humans can’t see in the dark so only notice moths when they are in well-lit places. This is one of the fundamental scientific questions that is yet to be answered.

WHAT ARE GLOW-IN-THE-DARK STICKERS COATED IN?

@dude_sparkles

Many different chemicals are affected by light in different ways. Some take in photons of light, which can cause electrons in the chemical to become excited and jump up to a higher energy state. In certain materials these electrons drop back down again and give off the energy as photons of light. This can happen fast or slow, depending on the material. When the energy is given off slowly it’s often called phosphorescence and can produce a soft glow that can emit visible light for a long time – newer materials for several hours even. As an interesting note, glow-inthe-dark stickers still glow even in the light; the light is just too soft to see.