So as we all know there is no gravity in space so, what would happen when you want to wring out a wet towel there? I fond this question very interesting when talking with friends so I thought I would take a deeper look into it. When you have a very wet towel and go to wring it out, the water is not just going to fall off like it does on earth. Instead because of the waters surface tension and lack of gravity in space, the water will float around the surface of the towel forming a tube shape around it. The water will stay like this until further actions are taken. I found this very interesting because you don't think of gravity effecting such small actions like wringing out a wet object until it is no longer present. After looking at this it would be cool to see how they get the water out of something super wet in space since you cannot just wring it out. The video below shows what happens when you try to wring out a towel in space.
With this wonderful weather comes wonderful roads. From driving, it can be a very dangerous with the coefficient of friction much smaller making roads very slippery. Thinking about our previous unit with rotational and transnational motion it can relate a lot with a car in the snow. When starting up the tires often spin when very slick out causing for more rotational movement rather then the wanted transnational. And then as you get going you begin to build more transnational rather than rotational. So for every one out there driving be careful!!!
How does a whistle work? In order for the typical whistle to work you need air streams. In order to get the high pitched noise that you hear coming out of a whistle you need the air steams to interact or cross paths. This is done through the round part of the whistle, as you blow into the whistle the air travels through the loop and up again (as seen in pic below) this allows the air to cross paths with the new air coming in. At this point where the air stream crosses itself again becomes a high pressure point and the air that escapes is what makes the noise. Whistle pitch and frequency depends on the length of the whistle, the longer it is the lower the sound will be. There are other types of whistles that work in a similar concept but vary slightly. The image below is the standard whistle that I am talking about.
When an explosive goes off under water the shock wave carries a lot further than it would if it were on land and in the air. This is cool because water has a higher density than air so this mean that it is harder to move or has higher inertia. And we know that inertia is a measure of how restive something is to acceleration. This means that after the explosion goes off the shock wave from that will carry further through the water with smaller deceleration. From this we know that this shock wave will be carried without losing speed and keeping it's high kinetic energy. As a result of this if you are anywhere near an explosion in the water you will be feeling most of the energy from the explosion. This energy from the explosion depending on the size could have enough energy to shatter every bone in your body. I would suggest getting out of the water if you were in this situation but, chances are you would be to late.
A turbo system in a car is a pretty simple but genius idea. It uses the gas exhaust from a piston engine to spin the turbine in the turbo system which then pumps more air into the cylinders of the car, allowing the car to burn more fuel each second. As a result of a turbo system, your car will burn more gas but because of this the turbo will provide the car with more power due to the increased revolutions of the pistons. By installing a turbo in your car you will be able to increase your cars over all speed. But without an anti lag system in your car there will a turbo lag meaning that when you press on the accelerator it will take a few seconds before you feel the full effect of the turbo.
Kronwall is one of my favorite defenseman in the NHL. The reason for this being his huge hits that he has (shown below) and this great defensive play. The reason for hit great hits is because he combines his massive self with a good amount of speed to completely wreck players. The main reason this is so effective is because of a fundamental aspect of physics which is the idea that momentum must be conserved. Since he catches his opponent off guard it allows him to build speed and use his mass to collide with the other played and cause for him to continue on in his original direction. Even though his speed gets slowed significantly from this it is because he has just collided with another massive player. But, since he has more speed and a better center of mass this opponent gets "Kronwalled"
It is better to not get hit in the head but sometimes it just ends up that way. Hockey helmets are designed like most helmets with the ability to absorb most of the energy from impact. The thing that I believe separates a hockey helmet from a standard football helmet is the fact that the top of the line hockey helmet rotates a little around your head without jerking your head in the initial impact. (I don't Know enough about football equipment to speak on behalf of the equipment) However, most injuries that occur to the head are caused from the initial jerk of the head when the brain remains still for a moment while the head moves. As this movement happens it yanks on blood vessels and nerves causing strain on the head and if bad enough an actual brain bleed or a concussion. This is why I wear the top of the line helmet now because previously having a really bad concussion and now I must wear it to prevent future ones. With this helmet no one is safe from every hit but with the ability to rotate a little around your head it gives you a slight edge over other helmets.
@Cvankerkhove had a blog recently about the butterfly effect. The butterfly effect is basically the idea that every thing that happens has an effect on everything else so if one thing doesn't happen everything else could be different. This got me thinking about the idea of time travel and how things would change if you were to go back in time and interact with other people. With this idea in mind what would change? Would the time line that you went back to, continue on and basically start all over again by living out all of the changes that you made to it while the time line that you came from, continues to live out their time line? Or is their just one time line that is being altered? This idea of different time lines is kind of like alternate universes which is a cool concept and it makes me question the conciseness of us right now and how there could be multiple of you on different timelines.
When you are walking in the snow have you ever noticed that when your foot lands in light, fluffy snow your footprint is actually bigger than it is and you can see the extra space with your foot still there? This happens because when you are bringing your foot down it traps a pocket of air between your foot and the ground. As a result of this once your foot hits the ground that air pocket is dispersed thus it causes for the snow around your foot to move even though you are not touching it. This can be pretty satisfying when you are walking home in the freezing cold with nothing to do.
So on the back of super cars you often find a spoiler. As a kid I always thought that a spoiler was just to make the car look cool but in fact it does serve many purposes depending on the positioning and type of spoiler used. One use of a spoiler is to push the air around behind the car as the car pushes through the air this reduces the drag force on the car. This application of the spoiler can improve gas mileage. Another reason why spoilers are seen on super cars is because when traveling a very high rates of speed it is often very difficult to control the car. By adding the right type of spoiler it can use the air that you are traveling through to push the back end of the car down, creating more downward pressure, this is know as counter lifting. This gives the car more grip that allows the car to have more power and control thus increasing performance. The car below is the mclaren p1, this is a car that makes use of a spoiler in order to keep it on the track and increase performance.
So with the hockey season starting today I thought that i would do a blog about hockey. Thinking about skating in hockey and why you need to get your skates sharpened, this is to allow for there to be enough friction to propel you forward. This is just like running were you need friction between the ground and your feet to be able to drive forward by pushing back. The only difference is that in hockey you need the skates sharp to cut into the ice in order to drive yourself forward. This is showing Newtons law where if there is a force in one direction there must be one in the equal and opposite direction. Being able to gain traction is hockey is key to being able to be fast that's why you angle your blades on the ice instead of straight on as you can see in the video below. You can also see how the players you there sticks to go into the turn to help get around the turn more compact instead of having it out wide which would slow you down.
So last Friday our class of 22 had the pleasure of taking part in a Projectile Lab in which we would shoot our grade. In this lab we would be trying to hit a textbook after making various calculations. Another important aspect of this lab was the fact that if we hit this book the whole class would pass and if we missed the whole class would fail. As many of you know this lab didn't go so hot, crunched for time and lack of communication lead to a complete miss. Mr. Fullerton, being the wonderful man that he is, allowed us to re-due the calculation and write about it in the blog I'm currently writing to receive full credit after that humiliating miss. After doing the calculation again, I came to the conclusion that the book should have been placed at the center of about 2 meters. The thing that messed the class up the most was the fact that there was a lack of time and the push at the end caused for a mix up with numbers due to not being able to think clearly stressed about the time.
After doing this lab and looking back on it, with some more communication it would have helped to make the lab go quicker so we aren't crunched for time also another idea would be to split into into small groups to get an answer which to then compare later instead of trying to work on it as a bigger group. I think that these things are key to this lab to allow for success.
Bellow are my calculations for the value in which the location of the book should have been placed.
So recently I had knee surgery, about four months ago on my right knee. Everything was going well and good until a few days ago. Come to find out I messed up my knee again but wait there's more, this time it was both of them. My right one definitely has another tear in the meniscus and the surgery is scheduled. But, the left knee, however, we were unsure of so i had to get a MRI done. During this I was curious to see how it worked but come to my amazement so was the guy operating it. Despite this I decided to research how it worked. I found out that an MRI machine is just a strong magnetic field ranging from .5-1.5 Tesla. An MRI machine uses this magnetic field to arrange hydrogen atoms in the body along the axis of the machine. once this is done the nuclei produce their own magnetic field that can be detected by a scanner and then form an image. I thought that this was really cool and the person to come up with an invention of this sort must have been absolutely brilliant. From this machine I hope that it gives me some good news so that I don't need three knee surgeries in a years time frame.
In order for a monster truck to be able to do a front flip it needs for one of its points far from it's center of mass to come into contact with a fixed object. One way of doing this would be to get the truck into a wheelie or almost stand the truck up, then you need to hit a fixed object like a very steep jump. This will cause for the truck to begin a rotational motion and begin to do a front flip. This is because the impact of the tires on the fixed surface act as a torquing force which cause rotational motion. In the video below the truck hits a jump to get the car into a wheelie and then increases speed to hold the wheelie so that the trucks back tires come into contact with a dirt ramp which cases the truck to perform a front flip.
Through photon camp in which I attended last year there was a lot of talk about lasers. This is because while using optics you can do a lot with lasers this is because you are easily able to manipulate them. The three things that all lasers have are an energy source, a medium and a resonator. The energy source or source pump is used to provide the laser with the energy that it needs to be powered. The medium is what really separates lasers because it determines the strength of the laser or the power that it has. And the optics are used to adjust and fine tune the beam. Lasers are cool because that have a variety of uses: cutting, welding, drilling, and marking. They are very good sources of light that are easy to manipulate and have endless uses.
So in the past month I have recently had Knew surgery to remove a torn meniscus. This surgery was relatively quick only lasting about an hour. Knee surgery has come a long way from where it use to be. They use to have to open up the whole knee but now you only walk out with three little holes in your leg. All the thanks goes to physics and the ability to manipulate things using modern knowledge of optics and modern technology. During this surgery they were able to take out a torn piece of meniscus with a viewing tool, a small scalpel, and water to flush it all out. This makes the surgery relatively easy and allows you to walk a day or so after and be back playing sports within two weeks. I am very thankful for physics for it got me back to hockey before the season began.
Today in class a cool thought was brought to my attention. The idea that an object that is an infinite distance away from all other objects will have no gravitational potential energy. Its a cool idea because if you think about any object on earth it has its own gravitational field due to the fact that all matter has mass. The earth is a great example of this because we can clearly see the moon and how it travels around the earth which is due to the gravitational pull by the earth on the moon. So thinking of the moon an infinite distance away from the earth than there would be no force acting on it saying that the only planets we are taking into consideration are those in this galaxy. It's weird to think this way with things at an unreachable distance becasue they are not possible and hard to wrap the mind around.
When a person is jumping from a high distances to the ground or other hard surfaces it is important to maximizes the time that you are decelerating. This is vitally important because the thing that causes injury is the force that is applied to you over short periods of time. If you can spread the force out along a period of time the impulse over time wont be a as big thus your body will not have to absorb all of the energy at once allowing for a safe landing. This also allows for the body to be able to absorb greater forces. One way to increase the time to stop is by bending the knees. This is very important because if you don't you will feel the force all through your body
A human body has the ability to release a huge amount of strength through its muscles. The reason that a person is unable to unlock all of this strength at any given time is so that muscles do not get strained or torn in the process. This is a cool safety feature of the body so that people do not over exert themselves and end up crashing. In order to produce large amounts of strength it takes a lot of energy and using muscles to their max for a long period of time can be very harmful to the body. However, in some cases when on an adrenaline rush people are able to tap into this strength in order to do things that seem to be humanly impossible. There have been incidents were people have lifted cars or moved heavy objects in order to save or do something. This shows just goes to shows how powerful the human body is.
So I recently came a crossed an article that said drinking warm liquids on hot days will actually cool you down faster than a cold drink. I found this really strange because I would have thought that a nice and cold refreshing drink would cool you down,however, like normal I was wrong. I thought that was really interesting so i decided to look into it. I found out that this is actually true. When drinking a hot liquid on a hot day it will cause you to sweat more than than usual, cooling you down. This is cool because with sweat being a natural cool down for the body it is cool how you can manipulate your body temperature so that you can do it more. Drinking a warm drink consistently allows you to produce about a 100 ml more sweat than if you were to drink a cold drink(A warm drink being 50 degrees Celsius and a cool drink being about 1.5 degrees Celsius) So if it a hot day and really want to cool down i suggest that you go grab some nice and hot tea even though a cold glass of water would sound better (which I will probably still drink on a hot day)
Thinking about what we have been learning in physics, on the topic of energy, it makes it more clear to see some of the physics that goes into taking a shot in hockey. I mean they go so fast but getting there was a little hard for me until this unite that we are in now. Looking at elastic potential energy you can clearly see that in the picture below. It's crazy to see how that potential energy is turned into kinetic energy in fractions of a second and the puck is sent flying at ridiculous speeds.
So this weekend my brother had a hockey game that I went to go watch. I traveled all the way to buffalo to watch his team get beat 5-2. Anyways, during his game he got absolutely destroyed at center ice. It sounds like it would really hurt but getting hit in the center of the ice isn't as bad as it sounds, getting hit against the boards it way worse which I know from experience (I have had my fair share of getting hit myself). But, this got me thinking of why it hurts more getting hit against the boards rather then at center ice. It looks as if it would hurt more getting hit at center ice but it actually doesn't thinking about force over a given period of time. Getting hit center ice means that the force that you get hit with is carried out over a longer period of time rather then against the boards meaning you will feel the force against the boards more because it is carried out over less time. Below are some examples of why it seems lik getting hit open ice would hurt more than at open ice.
The key to golf is not only patience but to have a consistent swing. If you can hit the ball the same way with the same force overtime you can be accurate with how far you hit the ball just by changing clubs. Each club has a different loft and an angle associated with it. Knowing the angle and the force exerted on the ball allows for you to be able to calculate the distance that the ball will travel using kinematics because you are able to find the horizontal and vertical forces suing the angle and these are needed to solve. And using a combination of force exerted on the ball and angle you are able to get an exact distance by changing these values. This will only work too if you know the changes in elevation and the idea that the ball is perfectly inelastic and that it has no rotational inertia which we know isn't true.
The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.
APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to firstname.lastname@example.org. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.