ClassX Video Lessons Youtube Channel The Engineering Mindset Battery Life Calculator – How long will it power a circuit? mah
Batteries are essential for powering our electronic circuits, but have you ever wondered how long a battery can keep a circuit running? When you look at a battery’s packaging or datasheet, you’ll often see a number followed by “mAh.” This stands for milliamp-hours, which is a measure of the battery’s capacity. For instance, a battery with a 2500 mAh rating can theoretically provide 2500 milliamps of current for one hour, 250 milliamps for 10 hours, or 20 milliamps for 125 hours.
In reality, a battery might not last as long as its mAh rating suggests. This is because the chemical reactions inside the battery slow down over time, and the battery’s internal resistance changes as it discharges. Other factors like the battery’s age and the temperature can also affect its lifespan. While there’s no exact way to predict how long a battery will last, we can make an estimate using a simple formula.
To estimate how long a battery will power a circuit, you can use this formula: Battery life = Capacity in milliamp-hours / Circuit current in milliamps. For example, if a circuit requires 19 milliamps and the battery has a capacity of 3000 mAh, you would divide 3000 by 19 to get approximately 157 hours. However, this is just a best-case scenario, and the actual time will likely be less.
We’ve created a simple calculator on our website that can help you estimate how long a battery will last and what capacity you might need. You can find the link in the video description.
That’s all for this lesson! If you want to learn more, check out the other videos on our channel. Don’t forget to follow us on social media and visit engineeringmindset.com for more educational content.
Gather different types of batteries and small electronic devices. Measure the current each device uses with a multimeter. Calculate how long each battery can power the device using the formula: Battery life = Capacity in milliamp-hours / Circuit current in milliamps. Record your findings and compare them with the actual performance.
Research various batteries and their mAh ratings. Create a chart that lists these batteries alongside common devices they power. Include estimated battery life for each device using the formula provided in the article. Share your chart with the class and discuss any surprising findings.
Conduct an experiment to see how temperature affects battery life. Use a battery-powered device and test it in different temperature environments (e.g., room temperature, refrigerated, and slightly heated). Record how long the battery lasts in each condition and analyze the results.
Using a simple programming tool like Scratch or Python, create a basic battery life calculator. Input the battery capacity and device current, and have the program output the estimated battery life. Share your calculator with classmates and test it with different scenarios.
Create an informative poster that explains how battery efficiency can be affected by factors such as internal resistance, age, and temperature. Use visuals and examples to make the information engaging. Display your poster in the classroom to educate others.
Here’s a sanitized version of the provided YouTube transcript:
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We use batteries to power our circuits, but how long can a battery power our circuit? When we look at the packaging or datasheet for a battery, we see a value with the letters “mAh” next to it. This is the milliamp-hour rating. For example, one battery has a rating of 2500 milliamp-hours. This indicates that it could theoretically provide a current of 2500 milliamps for one hour, or 250 milliamps for 10 hours, or 20 milliamps for 125 hours.
However, in real life, it probably won’t actually last this long because the chemical reaction slows down, and the internal resistance of the battery changes as it discharges. There are many other factors that affect this, such as the age of the battery and the temperature. There’s no precise way to calculate the lifespan; the best method is to simply test it.
We can, however, estimate the lifespan using the following formula: Battery life equals the capacity in milliamp-hours divided by the circuit current in milliamps. For example, in this circuit, we calculate a demand of 19 milliamps, and the battery has a capacity of 3000 milliamp-hours. So, 3000 divided by 19 gives us approximately 157 hours. But this is really the best-case scenario, and in reality, it almost certainly won’t achieve this.
We have also built a simple calculator on our website where you can estimate the time a battery will last, as well as the required capacity. Check that out; links can be found in the video description below.
That’s it for this video! To continue your learning, check out one of the videos on screen now, and I’ll catch you in the next lesson. Don’t forget to follow us on social media and visit engineeringmindset.com.
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This version maintains the essential information while removing informal language and ensuring clarity.
Battery – A device that stores and provides electrical energy for various applications. – The battery in the remote control powers it for several months before needing a replacement.
Life – The duration for which a device or component functions effectively. – The life of a smartphone battery can be extended by reducing the screen brightness.
Capacity – The amount of electric charge a battery can store, usually measured in milliamp-hours (mAh). – A battery with a higher capacity can power a device for a longer period before needing a recharge.
Current – The flow of electric charge through a conductor, measured in amperes (A). – The current flowing through the circuit was too high, causing the fuse to blow.
Milliamp-hours – A unit of electric charge that indicates the energy capacity of a battery. – The new phone has a battery rated at 3000 milliamp-hours, allowing it to last all day on a single charge.
Estimate – To make an approximate calculation or judgment of a value or quantity. – Engineers estimate the power requirements of a new device to ensure it operates efficiently.
Circuit – A complete path through which electric current can flow. – The light bulb will only turn on if the circuit is closed, allowing electricity to pass through.
Resistance – A measure of how much a material opposes the flow of electric current, measured in ohms (Ω). – The resistance of the wire affects how much current can flow through the circuit.
Temperature – A measure of the warmth or coldness of an object or environment, which can affect electrical components. – High temperatures can reduce the efficiency of electronic devices and shorten their lifespan.
Lifespan – The total time a device or component is expected to function before it fails or needs replacement. – Regular maintenance can extend the lifespan of a computer by preventing overheating and dust buildup.
