Abstract
For our final project, we decided to investigate how phone chargers, specifically iPhone chargers (as both of us use iPhones) work. For wired chargers, although there is more of a mechanical aspect rather than a physics aspect, we decided to research it because it would provide us with good additional information about how our chargers work. We found that Apple's adapter has a system that shuts on and of 70000 times per second to convert the voltage into 5 V. Wireless charging, also called inductive charging, is quickly becoming embraced by many, so we also decided to look into how that works. We found that the current in the coil in the Qi charging pad, generated by an external source (wall socket), induces a voltage in the coil in the phone, which charges it. Finally, we tried creating a device using magnets and thick copper wire that could generate a current in the wire. We used two different attempts to try and generate a current in copper wire, which we hoped would be transferred to the iPhone connecter via smaller copper wires and would charge the phone. We attempted to do this both with a spinning wheel of magnets and with a tower of magnets that we dropped the wire around; however, neither was successful at producing a charge sufficient for the iPhone to register that it was being charged. The first was unsuccessful because we actually, despite changing the locations of each magnet constantly, were not changing the flux, so there was no induced current (as EMF induced is equal to ΔΦ/Δt). In the second, where we believed we were actually changing the flux, we concluded that either we had faulty connections, the charging cord was malfunctioning (least likely), or our magnets were simply not strong enough to generate current significant enough for the iPhone to detect and charge with (most likely).
Although we did not succeed in our initial goal of creating a smartphone charger, we did learn a lot along the way about how charging - both wired and wireless - work, and learned how something that we now take for granted (plugging the charger into the wall socket) is actually incredibly complex and requires a significant amount of tiny functions. Additionally, we learned that although the numbers in the physics equations seem small (P = IV where P and V are 5 W/V, respectively, and I is 1.0 A), generating that amount of energy is actually quite difficult (even though we used sixteen magnets and five feet of copper wire).
Although we did not succeed in our initial goal of creating a smartphone charger, we did learn a lot along the way about how charging - both wired and wireless - work, and learned how something that we now take for granted (plugging the charger into the wall socket) is actually incredibly complex and requires a significant amount of tiny functions. Additionally, we learned that although the numbers in the physics equations seem small (P = IV where P and V are 5 W/V, respectively, and I is 1.0 A), generating that amount of energy is actually quite difficult (even though we used sixteen magnets and five feet of copper wire).