Someone check my math on this one. I believe a typical Leyden jar can store about one nanofarad (1 nF) of power. How many farads does it take to screw in a light bulb?
Benjamin Franklin’s kite experiment is one of those things you learn about as a kid and start to think is silly and made-up as an adult, but this was actually a real experiment that Franklin was fascinated by and far more interesting than the watered down children’s version. Of course, accounts may vary on whether or not he actually performed it himself, but by his own writings he saw to carrying it out in 1752 with the help of his son, William (who would later become Governor of New Jersey and then imprisoned for being a British loyalist and spy during the Revolutionary War, but that’s another story entirely).
The experiment wasn’t to “discover electricity” (we already knew about it) but rather to study if lightning was electric. In proving that it was, and figuring out potential practical uses for it through further experimentation, Benjamin Franklin was integral in the development of our modern world.
First, a nanofarad is not a unit of power, but of capacitance.
The energy in a capacitor goes as 1/2 * C *V*V,where C is capacitance, and V the voltage across the capacitor. For something like a 5 Volt circuit (common in computers), that 1nF capacitor has 12.5×10^-9 Joules.
Discharge that in 1 second, and you have 12.5×10^-9 Watts.
So for 60 Watts power, you’d need about 5 billion Leyden jars (with 5V, you’ll need more for a lower voltage, less with higher voltage)
OK, but it’s a Leyden Jar, which means that the voltage on it is more like 10,000 Volts rather than 5V. So the stored energy is more like 0.05 Joules. Discharge in 1 second and you’d have 0.05 Watts.
However, discharge times are likely to be a lot less than 1 second. With a resistance of 1 Ohm, the characteristic time of that Jar would be 1 nanosecond. 100ns for 100 Ohm, etc.
From 0.05W to 60W, you need 1200 Jars, but with the discharge time, you need to multiply that by a billion to run for 1 second.
So the 1 trillion jars looks about right, for 1 second of 60W power.
Actually, in a careful reading of the “report” on Franklin’s kite experiment, one sees that all the verbs are basically conditional. I.e., the whole thing is a thought experiment. But there apparently were people who wanted to see for themselves (i.e. reproduce what was not in fact an experiment) and got themselves killed.
Brian Carroll creator over 6 years ago
Someone check my math on this one. I believe a typical Leyden jar can store about one nanofarad (1 nF) of power. How many farads does it take to screw in a light bulb?
Benjamin Franklin’s kite experiment is one of those things you learn about as a kid and start to think is silly and made-up as an adult, but this was actually a real experiment that Franklin was fascinated by and far more interesting than the watered down children’s version. Of course, accounts may vary on whether or not he actually performed it himself, but by his own writings he saw to carrying it out in 1752 with the help of his son, William (who would later become Governor of New Jersey and then imprisoned for being a British loyalist and spy during the Revolutionary War, but that’s another story entirely).
The experiment wasn’t to “discover electricity” (we already knew about it) but rather to study if lightning was electric. In proving that it was, and figuring out potential practical uses for it through further experimentation, Benjamin Franklin was integral in the development of our modern world.
Masterskrain Premium Member over 6 years ago
Well, at least it’s SOMETHING! Better then throwing cheap paper towels at homeless, and hungry AMERICANS with no power, fuel, water, or decent food.
Baslim the Beggar Premium Member over 6 years ago
First, a nanofarad is not a unit of power, but of capacitance.
The energy in a capacitor goes as 1/2 * C *V*V,where C is capacitance, and V the voltage across the capacitor. For something like a 5 Volt circuit (common in computers), that 1nF capacitor has 12.5×10^-9 Joules.
Discharge that in 1 second, and you have 12.5×10^-9 Watts.
So for 60 Watts power, you’d need about 5 billion Leyden jars (with 5V, you’ll need more for a lower voltage, less with higher voltage)
OK, but it’s a Leyden Jar, which means that the voltage on it is more like 10,000 Volts rather than 5V. So the stored energy is more like 0.05 Joules. Discharge in 1 second and you’d have 0.05 Watts.
However, discharge times are likely to be a lot less than 1 second. With a resistance of 1 Ohm, the characteristic time of that Jar would be 1 nanosecond. 100ns for 100 Ohm, etc.
From 0.05W to 60W, you need 1200 Jars, but with the discharge time, you need to multiply that by a billion to run for 1 second.
So the 1 trillion jars looks about right, for 1 second of 60W power.
genome_project Premium Member over 6 years ago
Thank Ben for Bifocals, the pot bellied stove, and the rocking chair, too.
AndrewSihler over 6 years ago
Actually, in a careful reading of the “report” on Franklin’s kite experiment, one sees that all the verbs are basically conditional. I.e., the whole thing is a thought experiment. But there apparently were people who wanted to see for themselves (i.e. reproduce what was not in fact an experiment) and got themselves killed.
danketaz Premium Member over 6 years ago
Most importantly, if at all possible, get someone else to hold the string. (Trump wants to help. Let’s give him the honor.)