Low-cost air pollution sensors
“How can we produce low-cost air pollution sensors?”
Air pollution sensors are absolutely necessary for policy making. But for many developing countries, such technology is often too expensive. So how can we make the costs less prohibitive? Well, let’s use our engineering mindset to figure this out. We know that the main cost of monitoring air pollution comes from deploying sensors. But humans all over the world are already carrying advanced sensors with them, smartphones! A team at the University of California San Diego have developed a series of sensors that can communicate with a user’s smartphone using an app called CitiSense to perform real-time pollution monitoring. The goal of this project is to eventually to create a system in which entire communities can use to gather pollution data
Air pollution sensors
“How can we monitor air pollution?”
With the advent of industrialization, air pollution has become a significant issue in many parts of the world, inducing grievous health issues and productivity impairments. As such, governments and independent organizations are taking action to reduce this nefarious trend. However, before we can take steps to eliminate pollution, we must first know how much needs to be eliminated. To do this, engineers have developed air pollution sensors which can analyze the atmosphere for certain elements (ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrous oxide) for human analysis
“How can we attach two conductive wires together?”
Engineers commonly run into a problem. When working with circuits, we may need to extend our wire. However, it is physically impossible to do such a thing
Or is it?
Luckily for us, engineers can do the impossible. Let’s start with a few basic principles. We know that wires can conduct electricity. We also know that metal can also conduct electricity. And we also know that if we were to solidify a liquid that was between two objects it would connect the objects. So what if we were to take two circuits, expose their conductive centers, and then quickly melt some conductive metal between them to cause an attachment? Well, this is the process of soldering, which just so happens to be one of the most vital skills that any engineer needs to know.
How to make faucets more sustainable
“How can we make our faucets more sustainable?”
I want you to think about something. What exactly do you use to clean yourself after you have used the restroom? Well, if you live in a developed country, then you probably immediately think of faucets. Quite simply, without faucets, we would be unable to function in our daily lives! However, as engineers, we must always think more critically not just about the outputs of a system but the inputs as well. Specifically, faucets use water for their operation. And since water is an increasingly finite resource (especially in dry areas such as California), how can we modify these mechanisms to be more sustainable? Well, believe it or not, there is a very simple solution for this, having the faucets use less pressure! When less pressure is used, a smaller volume of water will be transported, thereby using less water!
“How do meat thermometers work?”
Meat thermometers are used every day to measure the temperature of meats. However, how exactly do they work? Well, let’s use our engineering mindset to find out. If we were to deconstruct one of these machines, then we would find out that inside the thermometer are two strips of metal with different heat coefficients. Upon the application of heat, both of these will expand at different rates, inducing twisting and therefore changing the dial at a constant rate!
Chemical activity series
“How can we predict if an atom will react with another atom or not?”
If you ever decide to take a chemistry class, you will probably have to solve a lot of chemical reactions sets. However, have you ever wondered whether or not if these sets can be achieved or not? Well, in the natural world, it has been empirically investigated that some elements are more reactive with others. And in fact, this has found to be a linear correlation. To illustrate, let’s say that elements x is more reactive than element y which is more reactive than element z, then element x will also be more reactive with element z. If you put together an entire list of all of the reactivities of the periodic table of elements, you would build something that is called a reactivity series. The most reactive element is fluorine [F], and the least reactive metal is neon[Ne]
How cement is made
“How is cement made?”
Cement is one of the most versatile materials on the planet. However, how exactly is it made? Well, let’s use our engineering mindset to find out. First, we must gather up its primal ingredients: limestone, clay, and others. Then, we must crush these rocks. Then we must combine this crushed material with other ingredients such as iron ore and feed it into a cement kiln. The kiln will then heat all of these ingredients, burning away some, and producing a red-hot compound known as clinker. This clinker must then be ejected into a cooling plant, and be mixed with gypsum and limestone to eventually form the cement that we know and love.