Física: Partículas Carregadas Em Condutores Metálicos

Hey guys, ever wondered what exactly is flowing through those metal wires when you turn on a light or charge your phone? It's not magic, it's physics, and today we're diving deep into how to figure out the type and number of charged particles zipping through a metallic conductor every second. We've got a super interesting problem here involving a current of 11.2 HA and the elementary charge of 1.6 x 10^-19 C. Stick around, because by the end of this, you'll be a pro at understanding current flow!

Understanding Electric Current in Metals

So, what's the deal with electric current in metals, guys? It's basically the flow of electric charge. In metallic conductors, these charges are carried by free electrons. Think of a metal like a crowded room where some people (electrons) are free to roam around. When you apply a voltage, it's like opening a door and giving everyone a nudge in a particular direction. The intensity of the electric current, measured in Amperes (A), tells us how much charge is flowing past a certain point per unit of time. In our case, the current is a whopping 11.2 HA. That 'H' usually means 'hecto,' which is 100, so 11.2 HA is actually 11.2 * 100 = 1120 A. That's a pretty substantial current, meaning a ton of charge is moving! The key players here are the charged particles, and in metals, these are overwhelmingly electrons. They are negatively charged, and their movement constitutes the electric current. The problem also gives us the elementary charge (e), which is the magnitude of the charge of a single electron (or proton), given as 1.6 x 10^-19 Coulombs (C). This value is crucial because it's the fundamental unit of electric charge. When we talk about current, we're essentially counting how many of these elementary charges pass a point every second. The higher the current, the more elementary charges are flowing. It's like measuring the flow of water in a river – a higher flow rate means more water molecules passing by each second. Similarly, a higher current means more fundamental charge units passing by each second. Understanding this relationship is the first step to solving our problem. We need to know what is moving and how much of it is moving to quantify the flow. So, remember, in metals, it's the electrons doing the heavy lifting, and their charge is the elementary charge we'll be working with.

Calculating the Number of Charged Particles

Alright guys, let's get down to the nitty-gritty of calculating the number of charged particles! We know the current intensity (I) is 11.2 HA, which we converted to 1120 A. We also know the elementary charge (e) is 1.6 x 10^-19 C. The relationship between current, charge, and time is given by the formula: I = Q / t, where I is the current, Q is the total charge, and t is the time. Since we want to find the number of particles (let's call it 'n') passing through a cross-section per second, our time (t) is 1 second. The total charge (Q) passing through in that one second will be the number of particles (n) multiplied by the charge of each particle (e). So, Q = n * e. Now we can substitute this into our current formula: I = (n * e) / t. Since we're looking at the flow per second, t = 1 s. This simplifies our equation to I = n * e. Our mission now is to solve for 'n', the number of particles. We can rearrange the formula to n = I / e. Let's plug in our values: n = 1120 A / (1.6 x 10^-19 C). Remember, 1 Ampere is equal to 1 Coulomb per second (1 A = 1 C/s). So, the units will work out nicely: n = (1120 C/s) / (1.6 x 10^-19 C). When you do the division, 1120 / 1.6, you get 700. So, n = 700 x 10^19 particles per second. To make this look cleaner, we can express it in scientific notation: n = 7.0 x 10^2 x 10^19 = 7.0 x 10^21 particles per second. This is a massive number, guys! It really highlights how many tiny charge carriers are actually moving to create even a moderate current. So, the calculation is straightforward once you understand the basic definitions and rearrange the formula correctly. We're essentially dividing the total charge flow per second by the charge of a single particle to find out how many particles make up that flow. Pretty neat, right?

Determining the Type of Charged Particles

Now for the million-dollar question, guys: what type of charged particles are we talking about? In metallic conductors, the charge carriers are almost exclusively free electrons. These electrons are part of the atoms in the metal, but they are not tightly bound to any single atom. Instead, they form what's called an 'electron sea,' and they are free to move throughout the entire metal lattice. When an electric field is applied (which is what happens when you connect a voltage source), these free electrons drift in a specific direction, creating the electric current. So, the particles carrying the charge are electrons. Electrons carry a negative charge. The problem states the elementary charge is e = 1.6 x 10^-19 C. This 'e' represents the magnitude of the charge of a single electron. Therefore, the charge of an electron is actually -e, or -1.6 x 10^-19 C. While the calculation for the number of particles uses the magnitude of the charge (e), it's important to remember that these are negatively charged particles. If the question had been about a semiconductor or an electrolyte, we might be dealing with positive charges (like 'holes' or ions), but for a simple metallic conductor, it's electrons. So, to summarize, the type of charged particle moving through the metallic conductor is the electron. This understanding is fundamental in electrical engineering and physics. It explains why current flows in a particular direction (conventionally, current is defined as flowing from positive to negative, but the electrons actually move from negative to positive). The concept of free electrons in metals is a cornerstone of solid-state physics and explains many of the electrical properties of materials. So, when you see a current flowing, picture billions upon billions of tiny, negatively charged electrons zipping along!

Putting It All Together: The Final Answer

So, guys, let's bring it all home and nail down the final answer! We've done the heavy lifting, and now it's time to combine our findings. We calculated the number of charged particles per second to be 7.0 x 10^21. We also determined that the type of charged particle moving through a metallic conductor is the electron. Therefore, the answer to our problem,