Hey Reader, Happy Wednesday! Let’s look at how Smoke Detectors in your home and office spaces work this week. I aim to write my newsletter issues in a way one can follow them while traveling on a bus, having a coffee, waiting for food, etc. Let's jump in! How it works: 15-second answerIonization smoke detectors, suited for flaming fires, contain radioactive material Americium between two charged plates. This material emits alpha particles, creating a current by ionizing air. But smoke disrupts this, stopping the current and triggering the alarm. Photoelectric smoke detectors, suited for early smoldering smoke, use a light beam and a light sensor (photodiode). In clear air, the light beam doesn't reach the sensor as they are not in line. Smoke scatters the light onto the sensor, generating current and activating the alarm. Modern detectors often combine both technologies for enhanced safety. How do Smoke Detectors work?There are two mechanisms used by smoke detectors. Let's explore them one by one. Photoelectric Smoke Detector:Setup: Inside the smoke detector casing, we have an infrared LED beam striking the other end. A photodiode sensor is placed at an angle within the casing away from the light beam. A photodiode is a sensor that generates current when light falls on it. The higher the intensity of light that falls on the sensor, the higher the current generated by the sensor. How it works:
This type of detection technology is typically suitable for situations where there is slow-burning smoke. What about the case of flaming fires? Ionization Smoke Detector:This mechanism of smoke detection is more exotic but not necessarily better than the previous one. Setup: Inside the plastic casing of a smoke detector, you can typically find a 9V battery that powers two plates, one with a positive charge and the other with a negative charge as shown in Figure 2. A tiny amount of radioactive material called Americium is placed near one of the plates. Americium constantly emits alpha particles due to its radioactivity. The air in our environment (consisting of 78% Nitrogen and 21% Oxygen) reaches the space between the parallel plates by going through the openings of the smoke detector casing. How it works:
This is how smoke detectors work! Activity of the week
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Gadget of the weekNamocell Single Cell Sorter: A California-based biotech company working on a device that can pick and sort individual cells from a mixture, like sorting different types of tiny beads. It uses special technology to see and identify cells based on their light signals. This machine helps scientists study single cells in detail, which is important for research in areas like genetics, cancer, and personalized medicine. Thank you for reading! Have an amazing rest of the week, and take care! Read all the past newsletters, about me, or suggest a gadget for me to write about
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