Final Tech Blog post

Its the end of the year, and the end of technology 6 quarterly. While having to do the whole quarterly online and on zoom definitely isn’t as fun as being at school in person, it wasn’t too bad. To recap all the things I learned during tech :

Glue and adhesives

Mechanical engineering and the different shapes and their strengths

i beams

Simple machines

Work, levers and gears

Atoms

electrons, protons neutrons

electricity

batteries.

As a final post for tech 6, I would like to thank mr. Calvert for an amazing e-learning tech experience.

Electricity around us

Electricity is all around us. We use it to power things, to make heat and light, and to cool things. Many of us have electrical sockets in nearly every room in the house. Whether we use these to charge an iPhone or to plug in a fan, we are still using electricity. From driving a car, to something as easy as turning on the lights, these all use electricity. We don’t appreciate electricity for what it is, and the use of electricity has become so commonplace us, that we almost forget that it was ever there. Us humans rely on  electricity so much, but don’t give it the appreciation it deserves. So the next time you go somewhere, look at everything, and realize how much electricity is around you. Learn about electricity, realize how much electricity we depend us, and appreciate it.

Where does gold come from?

Gold is one of the most electrical conductive elements in the world. However, gold doesn’t come from this world. Gold is the byproduct of supernovas, or when a star collapses on itself and explodes. The large amounts of energy allow heavy elements to be created such as gold. It is created in a second and then distributed out into space.  Uranium can also be created. This explains why gold is so expensive, and is not found in large quantities at once.

Ideal mechanical advantage. And ramps.

Ramps are cool.  By extending the distance outwards, we can push things up to the same height if we were to lift it, but it is easier. By extending the distance, the work still remains the same, but since the distance is longer now, that means we put in less force. And now for mechanical advantage. Mechanical advantage (or MA for short) is how much more easier it is to do something compared to doing it without the machine. So if you had to push a block up a ramp, and the ramp had a mechanical advantage of 2, then the block would be 2x easier to push up the ramp, then just lifting the block to the same height as the ramp. For more on this, I will leave a link at the bottom which will take you to another page talking about mechanical advantage.

 

Anyway,let’s do a practice problem! So we have a box full of stuff. And it is heavy. So we make a inclined plane for it. We want to lift this box 5 feet in the air, but now we have a ramp that is 30 ft long. So if we calculate the MA, which is the length over the height, we get MA=6. So our mechanical advantage is equal to 6 right?  Well, no. It gets more confusing. The MA isn’t 6, the IMA is 6. It turns out, that there is two types of mechanical advantages. Ideal mechanical advantage (IMA) and actual mechanical advantage (AMA). Today, I will be talking about IMA and maybe in a later blog post I’ll talk about AMA .

 

Ok, so what does Ideal actually mean? Well the dictionary definition of ideal is – something that we want to happen, but won’t actually happen in reality. So in short it means to imagine a perfect world with no blemishes.

So, in our last practice problem we got 6 for IMA, but why is it IMA? Well, in the problem we are imagining a world where there is no air resistance and friction. In this ideal world, the only factor here is the box and the ramp. However, in the real world, there is something called friction. This will slow down the box, meaning that the AMA isn’t 6 but actually the AMA <6. So basically, the IMA what the MA would be in a world that doesn’t have any other factors except for the machine and the load.

 

How to calculate IMA.

IMA is basically the length of the ramp/ the height for a ramp/incline plane. IMA = L / H for a ramp. However, IMA doesn’t only apply to ramps. Levers also have IMA formulas, and so do all other simple machines. For levers it is the effort arm length over the resistance/load  arm length.

 

 

IMA and AMA was confusing to me at first, but after a while I got the hang of it. Learning that there were two types of MA confused me for quite a while but after more research and watching videos, I understood most of it. Some of this information may not be correct because I didn’t spend that much time reading through websites and watching videos on the topic, so feel free to correct any mistakes I made. In a later blog post, I will talk about AMA and the difference between the two mechanical advantages. Please check out my other mechanical advantage blog posts ( this is becoming more of a series about mechanical advantage). I will leave a link down below to all my posts about mechanical advantage. Thank you. Bye. Nothing else to say. If you have any questions put them in the comments and I’ll do my best to research and answer them(or you could just google it yourself).

 

 

 

 

 

http://blogs.scarsdaleschools.org/plin26/category/technology/mechanical-advantage/

link to my mechanical advantage stuff ^

 

http://blogs.scarsdaleschools.org/plin26/2020/05/26/what-exactly-is-mechanical-advantage/

 

Link to my what is mechanical advantage post ^

 

What exactly is Mechanical Advantage??

So, what is Mechanical advantage and how does it work? After doing much extensive research and reading (aka a google search), I have come to a conclusion (we learned this in class, I’m just kidding about the google search). Mechanical advantage, also written as MA in formulas, is a number that doesn’t have any meaning. Ok, fine. The number that you get when calculating mechanical advantage is how many times the input force the machine will output. Have I lost you yet? Ok, to make this simpler and easier to understand, imagine that you go to a store and buy a lever that will throw a ball. It advertises that the machine has a mechanical advantage of 1. Great!  You think as you go to buy it, “ One is better than zero” So later, you go put the contraption on your arm to see how much farther you throw now. To your surprise, you seem to be throwing the ball the same distance! So you take off the machine and throw the ball normally. Lands in the same spot. That’s when you realize that any number multiplied by 1 will be the same and you just got ripped off. So the moral of the story is don’t fall for scams and don’t waste your money on stupid things that won’t do anything for you and make sure you can get a refund! Ok, but as it turns out, a low mechanical advantage isn’t too bad. Check out my other post for me going deeper into a topic that I don’t understand! So, Peter, some of you might be wondering. Did you make a story about mechanical advantage just to make your blog post longer? To that my friends, the answer is yes. However you can take away some things from the story, like how mechanical advantage works and I already told you what it is, but the most important lesson of all is…um…. hold on…. you know what, I give up,  just decide for yourself.

 

http://blogs.scarsdaleschools.org/plin26/2020/05/25/ma/

Link to my other blog post about MA that I don’t recommend you read.

MA<1 ?

Recently, I made a catapult which uses a lever and we had to find the mechanical advantage of the lever. However, while I was looking through some other people’s catapults, I was constantly seeing MA which was less than one. From what I know, MA is the ratio of how much force the machine will output from the input force. So a MA of 4 would mean the machine would output a force 4x the input. If so, then what is the point of a MA less than one? Would it still be an advantage? If a mechanical advantage is less than one, that means that the input force would be higher than the output, so wouldn’t it be easier just to do it without the machine? So I did some research over the weekend. First let’s start off with levers. If the effort arm is closer to the fulcrum then the load, the mechanical advantage will be lower. This means that all 3rd class levers will have a MA <1 , 1st class levers could also have a MA <1. However, second class levers will not do this.

So then, what exactly is the point of a 3rd class lever? First let’s look a a 3rd class lever.

This baseball bat is a third class lever. As it turns out, the point of this third class lever baseball bat is not power, but speed or velocity. We exchange MA for speed, the baseball bat is one piece, meaning the side that you are holding when you swing, that side will move quicker than the other, so in order for the other side to move at the same speed and time, the velocity of that side must increase causing the bat to go at a faster speed. Which means when the bat hits the baseball, the baseball goes faster. So the point of the 3rd class lever is to make things go faster, or increase their velocity, right? Well, not exactly. That is the main reason for a 3rd class lever, but there are others too. For example, take a some tongs. Tongs are a third class lever. But the point of tongs isn’t to make something go faster, the point is to pick something up. Usually we use tongs for ice. What is the problem with ice? Ice is slippery and hard to pick up ( also no one wants your dirty hands touching the ice that will go in their drink) so we use tongs. MA doesn’t really matter here, because ice is so light, that we will only be losing such a small force, that it isn’t really noticeable. Tongs are also used to pick hot food up, because we don’t want to burn ourselves. Again, food is usually so light that the force lost isn’t noticeable. We don’t care about the small amount of energy being lost, we care about getting food. So 3rd class levers have all kinds of usages, and just because they have a mechanical advantage of less than 1 doesn’t mean they are completely useless.

 

FabMakerStudio

Last week in technology, we used this design website, called FabMakerStudio. It lets students design 3D or 2D things out of paper, so it’s kinda like CAD but not really? Anyway, I made a barn [see image below] from the list of pre-made 3D paper designs. This project involved a lot of cutting and glueing, which took some time but not a lot. The barn was originally supposed to have moving doors and windows, but that was too hard to be cut with scissor so I just cut out the door and glued it onto the barn. I made a paper barn using FabMakerStudio, and I really like it.

 

 

Truss

I forgot to do a blog post last week, so I will do two this week. The next one will come out tomorrow. So in technology I made a cube out of toothpicks and marshmallows. Then I put books on it. Collapsed after only three. Then I realized that I forgot to film it for flipgrid, so I had to do build it again.  I also built a  cube with trusses. The cube without supports could only support a little weight before it collapsed, while on the other hand the one with trusses held up much more weight before the it finally broke.

I beam stuff

Yesterday I made an I beam out of cardboard and compared it against just 6 strips of cardboard. The I Beam held up more weight than the pieces of cardboard. I don’t have anything else to say so I did some more research on the I beam and found out that there is a formula to figure out how strong the I Beam will be compared to other shapes. This is called area moment of inertia, and, yes I memorized this, the formula for an I beam is, assuming the I beam is on it’s x axis (I’ll put a picture down below of the I beam) is : I sub x = (a h^3/12) + (b/12)(H^3-h^3). If on the y axis, then it is  : I sub y = (a^3h/12) + (b/12)(H-h). The number you get at the end is just a representation that you can use to compare with other shapes. The a is the width of the web, h is the height of the web, H is height of the whole thing, and B is the width of the flanges. Why 12? It’s derived from physics, and I’m not going try to figure that out. The rectangle cardboard is more simple it is I sub x = bh^3/12 and I sub y is b^3h/12. b and h is base and height. The higher the number you get, the more weight the beam can withstand. The website I learned this from is called Engineeringtoolbox.com and it has lots of other interesting stuff about engineering.

I beam picture

 

How did I transfer energy this weekend?

I woke up, used mechanical energy to get out of bed, I went downstairs to eat. When I was eating, I  used mechanical energy, to swallow the food, then, my stomach used energy to break down the food and create more energy. Then I went to take a shower, I turned the knob which used mechanical energy, and since the knob had potential electrical energy, it now turned in to kinetic electrical energy, and turned the shower on. It was too cold so I turned the knob even more, which converted electrical energy, into thermal energy, which then heated the water up. After that I went back to sleep and waited until it was lunch.