HAZ CLICK AQUÍ PARA VER EN ESPAÑOL There are plenty of curious scientific facts outside in the middle of the summer when it’s warm and sunny. We are so surrounded of so much science you look at without giving it a think. How does sunscreen work? In every sunscreen bottle you will find the acronym SPF followed by a number. SPF stands for Sun Protection Factor and indicates how long it will take for UVB rays to redden skin when using a sunscreen, compared to how long skin would take to redden without the product. For example, an SPF of 15 would allow you to stay in the sun 15 times longer than you could without protection. So, if your skin starts to redden in 20 minutes without sun block, applying a product with SPF 15 increases that...
HAZ CLICK AQUÍ PARA VER EN ESPAÑOL When things don’t turn out as we expected there is always somebody that says: “that’s Murphy’s law”… because, according to this law, if anything can go wrong, it will. Where does this idea come from? Edward Aloysius Murphy was an aerospace engineer. It was in 1949 when his assistant connected all the electrodes of a safety-critical system wrongly, so all the measures were wrong. Since then, this pessimistic law shows up every time it rains… because there is always somebody who washed his car or the windows the day before But all the bad luck we claim to be Murphy’s has a scientific explanation. Science behind Murphy’s law You may think things never come out the way you want, but that’s because you picture an ideal, perfect, unique and therefore...
What if everyone jumped at once? When you jump nothing seems to happen to the Earth… but what if, you gather some friends, and what if, you were so nice everybody literally like you and wish to meet you just for the experiment of jumping together. There are tons of us! we share the planet with 7 billion other people, so… what would happen if we met with literally everybody to jump at once? First things first… where should we meet? Where do we all fit? If the whole humanity lived with the same density there is in New York we could fit in the Iberian Peninsula. If we stood shoulder to shoulder we could all fit into an area the size of London. So ok… let’s imagine we all meet in London and jump together. My...
Does Turning Fluorescent Lights Off Use More Energy Than Leaving Them On? It’s usually said that letting the fluorescent on when you are leaving the kitchen only for a few minutes saves energy. Is this true? Turning a fluorescent light on requires more energy than keeping it on. The energy used during to turn the fluorescent on equals 23.3 seconds of regular use. So, in terms of energy letting the lights on pays off only if you are Fernando Alonso and you left the kitchen in order to change the tires of your F1. Other lights need even less energy in comparison: Switching.on Time on (seconds) Incandescent bulb 0.36 Compact fluorescent 0.015 Halogen bulb 0.51 LED bulb 1.28 Fluorescent tube 23.3 But you may be thinking, what about the wear and tear of the fluorescent tube?...
Sometimes it looks like moms gather secretly to decide what is the next thing they will say to their kids. If you are Spanish your mom certainty says to you: Drink your juice or it will lose its vitamins. Every mom will explain you that fresh orange juice should be drunk immediately after oranges are squeezed because else it will ‘lose its vitamins’ Like vitamins were little creatures that run away when you are spreading the jam on your toast! Orange juice is indeed a source of vitamin C (Also known as ascorbic acid) that oxidizes when it gets in contact with the oxygen in the air. The question is… is this oxidation as fast as our mothers say? Should I drink the juice directly from the squeezer? It is not. If you and your juice are at room...
HAZ CLICK AQUÍ PARA VER EN ESPAÑOL Science is fun and cartoon producers know it. There is a scientist character in many cartoons. In Dexter’s laboratory a scientist is the main character and in the Powerpuff girls Professor Utonium is the responsible of the girls having superpowers. Although it’s more common to find the scientist to be a secondary character and the perfect excuse to show a bizarre invention! That’s the case of professor Frink on The Simpsons, professor Hubert on Futurama or professor Bacterio on Mort & Phil. But even in cartoons where there is no scientist character we can learn plenty of stuff about science. SCOOBY-DOO There is something very important to learn from Scooby-Doo. Every episode begins with our four teenagers and their dog discovering that something paranormal is happening and every episode finishes explaining somebody...
Weighing light staff Have you ever found difficult to weigh something because it is too light? Recipes know this can be a trouble and that’s why you will read 100 ml of milk or 150 g of flour but you will find a pinch of salt instead of 2 g because recipes know the scale you have at home is unable to weigh that little. There are many things that you cannot weigh with your regular scale… like a post-it, a feather or a pin. You would need a precision scale for that. There are other things that are even more difficult to weigh, like air. Does air weigh at all? Yes it does! It’s vey light though and you will need some stuff to do it in your kitchen. Do you want to try? You can do...
An eclipse is an astronomical event when one celestial body partially or totally covers another celestial object. We can see two kinds of eclipses from Earth: eclipses of the Sun and eclipses of the Moon. Solar eclipses When the Moon passes between the Earth and the Sun. The Moon blocks the light of the Sun and a shadow of the Moon is cast on the Earth’s surface. There are three types of a solar eclipse: total, partial, and annular. A partial eclipse will also occur if the Sun, Moon, and Earth are not precisely lined up. The eclipse cannot be total unless the center of the Moon’s shadow is able to strike the Earth. An annular eclipse occurs when the Moon is at its farthest distance from the Earth and the Moon appears too small to completely block out the...
Cricket Calls are Nature’s Thermometer To convert cricket calls to degrees Celsius , count the number of chirps in 25 seconds, divide by 3, then add 4 to get the temperature. For example, you will hear 48 calls in 25 seconds when temperature is 20ºC because: 48/3 + 4 = 20° C Crickets chirp by rubbing their wings or legs over each other. Only the males of the species make this noise and they do so to attract mates. The notion that counting the chirps of crickets can serve as an informal way of getting the temperature is not new. In 1897, physicist Amos Dolbear proposed the reverse of that idea, stating that outdoor temperature determines the number of cricket calls heard. Over the years, his way of looking at this relationship was turned around, people now count the chirps to...
Both Alberto and I love the snow. I go skiing and he goes snowboarding and as we haven’t ever been together in a snow trip I’ve decided to share some of how this activity looks like to me. When you are a scientist you wake up in the morning in a nice village a few kilometers away from the ski resort, let’s say in the Pyrenees, you look up at the sky and then you wonder: How can there be clouds in winter when it is too cold for water to stay as a vapor? Although clouds look like they are made out of vapor that’s not true. You may notice when cooking that water vapor is invisible… so, why would that be visible on clouds? Water vapor is invisible because its molecules are too far apart to optically scatter light so there has to...
