Not many people put a whole lot of thought into what their morning cereal is made of. Most people would just assume there's some grain and maybe a little sugar, or a lot of sugar if you're more of a Lucky Charms person than a Raisin Bran person. Nobody would suspect, though, that there would be metal in their Cheerios. Turns out, Cheerios are magnetic. Or are they?
Fill a bowl with water and drop in a couple Cheerios. Take a magnet and hold it just above the Cheerios, the Cheerio will be attracted toward the direction of the magnet. Why is this? If the little cereal ring is magnetic, then there must be metal fragments in it causing the attraction. Now the cereal is all magnetic, and it does contain tiny fragment of iron. This is perfectly reasonable though, as iron is a key nutrient in a human diet. But that's not the whole story,
If you were to try this with objects other than cereal, say a small piece of paper or plastic, it would still seem to be attracted to the magnet as it floated in the water. The "attraction" you see is actually all about water, which is diamagnetic, meaning it generates a magnetic field opposite to that of the magnetic field it is in the presence of. Thus, the water is slightly repelled by the magnet. This causes a slight divot in the water, that the object in the bowl actually falls into, making it appear to follow the magnet. In actuality, it isn't being affected directly by the magnetic field, but by the waters reaction to the magnetic field.
During archery in gym class, I'm usually one of the people who gets my hands on the nicer quality bows. But today I was sad to find myself with one of the weaker, green bows. I had never shot with one of these bows, so when I took my first shot the same way I normally would, I was surprised to find that it fell to the ground just before hitting the target. I realized that this was simple physics, and I could easily fix my shot.
The green bows have much less tension in the string than the longer wooden bows, meaning that when released, they exert less force on the arrow. So my arrow was leaving the bow with a much slower horizontal velocity than normal. Obviously, the downward acceleration wouldn't change. So all I needed to do was to aim slightly higher than where I wanted to hit on the target, so that the arrow had more distance to fall, and didn't hit the ground before reaching its destination. After realizing I just needed to shoot higher, my shots were much improved.
One of the endlessly fascinating things about physics is that it's in literally everything. Makeup is one of my primary hobbies, and I've noticed many aspects of physics in my daily routine.
Whether you're using a makeup brush or a makeup sponge to get that flawless finish, you create a lot of friction on your face. In fact, the level of friction you apply will determine the quality of your application. Not enough, and you'll look a patchy mess. Too much, and you probably irritate your skin and defeat the purpose. A perfect balance of friction is what will lead you to a soft blend.
Also, density plays a huge roll in makeup. When choosing between kinds of base makeup, from foundation to BB creams to tinted moisturizer, you have to know the kind of look you're going for. The denser the formula, the higher the coverage, and the thicker the finish.
On a semi-related beauty note, static electricity is also a common battle in hair. This doesn't affect everyone, but being someone who has thick curly hair, I know too well the pain of having to carry dryer sheets to calm staticy hair.
Lastly, every makeup lovers worst fear is gravity. The unfortunate acceleration due to gravity on all objects is never more real than when a compact or favorite pressed pigment slips from your hand and plummets to the ground. Seeing the powder shatter truly is a tragic moment, causing you to curse gravity. Everything is physics, and it can be fun to notice it in simple daily tasks.
Citizens of the Rochester area experienced a weather crisis of dangerous proportion a couple weeks ago, to varying degrees. When I realized the power was down,I was excited for what I assumed would be a temporary break from school, and physics, but was disappointed. My father, being a type-A scientist type, found a way to bless me with the joy of physics even during our dark age adventure.
My home had no electricity for days, and therefore no heat. We do, however, have a wood stove with a blower.The blower requires electricity, and my father keeps a deep cell battery for emergencies. So my dad would charge the battery on his car, then plug the stove blower into the battery inside the house. He used a voltmeter to periodically measure the voltage, to watch for when it needed to be recharged.
He used this chart, not letting the battery drop past 30%, to be as safe as possible. And boy was I thankful for this battery, as it kept our home warm enough to live in and allowed us to charge out phones. Also, the monitoring of the battery kept my dad busy and out of my hair.
Does everyone remember that day in science class when they told you the Earth was round, and you were like, "Yeah, no duh." And then a couple of years later they told you the Earth was also incredibly smooth, and you kinda just went with it. And then they said if you held an orange and a billiard ball in your hand, and then you could also hold the Earth, that it would feel more like the billiard ball than it would the orange? And that's when you got real confused. What about all the super tall mountains and super deep valleys and the trenches and the oceans? It made sense eventually though that these features were rather small compared to the whole mass of the planet. So now the Earth is one of the smoothest things you can think of. But there actually is one thing on Earth that is the most roundest, smoothest thing to exist on our planet: a ball of silicon. This sphere is officially the roundest thing humans have created; if it were Earth, the distance between its highest and lowest point would be 14 meters.
The reason it was created is pretty cool too. The sphere is an attempt to create a substitute fir the current definition of the kilogram, as this measurement is currently dependent on a physical object called "The Big K" that is locked away in some basement in France. The problem is that there is no way to keep this object from being warped over time, and the definition of a kilogram therefore changed. The creators of the silicon sphere hope to use the amount of atoms in that sphere as a new constant that would replace the kilogram.
First of all, unpopular opinion: The Bee Movie is awesome. It's funny, and cute, and you can't go wrong with Jerry Seinfeld. But as with any kids movie, the physics are way way off. What I found interesting though, was the movie's own mention of faulty physics, in the bees and their ability to fly. People always say that bees aren't supposed to be able to fly and scientists don't know how they can, but I called baloney and looked it up. The movie begins with a line "According to all known laws of aviation, there is no way a bee should be able to fly." Which is wrong. Turns out, scientists have figured it out, and the reason they hadn't before is pretty funny. They studied flight by comparing it to manmade aircrafts, instead of isolating animal behavior. Obviously insect flight won't always obey humans so called "laws of aviation". Bees have a freedom with their flight, and are able to change their wingspan in order to increase amplitude, without increasing the frequency of their wingbeats, which is higher than smaller bugs. This centuries old argument of the incapability of science can finally be put to rest. So don't worry Barry, we've finally got you figured out, keep flying buddy.
To say that Doctor Who does make sense would be ridiculous, but I'm not talking about any one episode. The entire plot line of the second version just doesn't hold up.
For anyone who hasn't seen DW (what are you doing with your life?) the Doctor is basically a time traveling, galaxy hopping vigilante. In the first version, the doctor traveled with all kinds of companions, including people from his home planet, Gallifrey. In the second version, the Doctor has just "returned" (emotionally and physically kinda?) from a battle called the Time War in which everyone from his planet, except for himself, have been killed. So the entire premise of the second version is that the Doctor is now the last of the time lords and is alone as a species, which makes him a little extra nuts.
But for every theoretical physics reason, this makes no sense. First of all, the idea that he is the one and only survivor is silly. And obviously, time travel. The Doctor could travel to literally any time in the past, as he does incredibly frequently, before the Time War, and just have a little reunion with past Gallifreyans. And given that the majority of the Doctors people are also time travelers, some of them could be wandering the future, as well as have escaped the war too.
Secondly, its canon that Doctor Who supports multiverse theory, as the Doctor has traveled to alternate realities many times. So whats stopping the Doctor from just popping into another reality where the Time War never happened if he wants to visit his friends so badly? Could it be plot holes??? And no, nonsense about altering realities and the order of time doesn't fly here, because it's been made glaringly obvious that the Doctor has become pretty apathetic about keeping time stable.
Anyways, for anyone who ever wants some cool sci-fi with lots of crazy (totally legitimate) physics themes, give Doctor Who a shot.
My little brother is in 6th grade, and has for the past week been working on the iconic egg drop project. I've been told that all 6th graders in West Irondequoit get to do an egg drop, and have heard interesting stories from friends about their experiences. I never got to do an egg drop in elementary school, so I'll admit I'm fairly bitter. But out of respect for the egg drop I'll put this aside.
I have a lot of appreciation for this egg drop project, as it opens younger kids minds to physics. My brother told me that his teacher introduced the project with a demonstration. She held up a small rock and a crumpled piece of paper, and asked which would fall faster. The kids all assumed it'd be the rock, except for my snarky know-it-all of a brother who said he knew they were wrong. She dropped them, and they reached the ground at the same time. This blew the kids minds, except for one.
This is a simple physics concept, and one of the first ones you're taught in any physics course. I'll admit that I'm still not comfortable with it; I get it, but something about it just irks me. But that's physics for you, there's complexity even in the simplicity. I think we can all take comfort in knowing that as hard as the math and calculus of physics get, the fundamentals will always be there to really mess with your psyche.
Regardless, I appreciate that my brother has been introduced to even this simple version of physic, and that he feels so interested in it. Kids should be more exposed to science and physics, especially if they show interest. Teach a kid some physics today!
Through a series of unfortunate events last weekend, I was forced to sit through a viewing of Twilight. In all honesty, it isn't that horrible of a movie. But what I found most entertaining was the abilities of the blood suckers. You can't really critique the physics of vampires, because who can say that their insane abilities wouldn't be made possible by magic or sparkles or something? But either way, I still have questions. In the movie there's a scene where the characters play vampire baseball during a storm, as they need the thunder to camouflage the sounds of them playing. So my question is: how hard would a baseball really need to be hit to create a noise as loud as thunder?
I found that your average clap of thunder registers at about 120 decibels. Some of the loudest cracks of a bat will only come to about 30 decibels. To create that sound, a batter exerts about a 35,000 N force on the bat. Just with that information, one can imagine what an incredible amount of force the characters must be capable of to create such a loud sound with the bat and by running into each other. It sounds like a baseball game I'd actually like to attend, although it'd be impossible for a wooden baseball bat to withstand that kind of force without splintering, regardless of the legitimacy of super strong vampires.
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