5 ms·

The problem I have with this sort of popular water analogy is that I don't really have any better intuition on hydraulics or fluid mechanics than I have on elec

by zokier 6y ago

The problem I have with this sort of popular water analogy is that I don't really have any better intuition on hydraulics or fluid mechanics than I have on electronics. Maybe this has been different in the past when the water analogy was introduced, but I don't see it being very useful at least today.

Cerium 6y ago
Interesting. I spent a lot of time in my childhood playing with water in the sandbox, perhaps that made the analogy more real.
- c22 6y ago
  For me it was playing Pipe Mania [0][1]. [0] https://en.wikipedia.org/wiki/Pipe_Mania https://en.wikipedia.org/wiki/Pipe_Mania [1] https://archive.org/details/win3_PipeDr3x https://archive.org/details/win3_PipeDr3x
- knodi123 6y ago
  so I guess water in a sandbox is the hydraulic analogy version of scuffing your feet on a shag carpet?
creeble 6y ago
Let me try with just the analogy of a hose and your thumb. Water is flowing out of the hose at some rate. If you put your thumb over the end of the hose, you can create a stream of water (of less volume) that shoots out a farther distance because of increased pressure (you can feel this pressure increase in your thumb). Think of amps as the volume of water, and voltage as the pressure. Power is voltage times current, or pressure times volume of water. You could squirt a stream of water many feet (raising the voltage), but it's not a very large quantity of water (amps). Conversely, with your thumb off the end of the hose, the pressure (volts) isn't very high (it just flows out at whatever your tap pressure is), but the volume of water is significant (amps). Curious whether that is any clearer of an analogy?
- globular-toast 6y ago
  The thumb is commonly used as an analogy for a resistor because it limits the current. But with the hosepipe it seems to increase the voltage, which a resistor does not do. What you describe (trading current for voltage) is more like a transformer.

by zokier 6y ago

Cerium 6y ago

Interesting. I spent a lot of time in my childhood playing with water in the sandbox, perhaps that made the analogy more real.

c22 6y ago
For me it was playing Pipe Mania [0][1]. [0] https://en.wikipedia.org/wiki/Pipe_Mania https://en.wikipedia.org/wiki/Pipe_Mania [1] https://archive.org/details/win3_PipeDr3x https://archive.org/details/win3_PipeDr3x
knodi123 6y ago
so I guess water in a sandbox is the hydraulic analogy version of scuffing your feet on a shag carpet?

creeble 6y ago

Let me try with just the analogy of a hose and your thumb. Water is flowing out of the hose at some rate. If you put your thumb over the end of the hose, you can create a stream of water (of less volume) that shoots out a farther distance because of increased pressure (you can feel this pressure increase in your thumb). Think of amps as the volume of water, and voltage as the pressure. Power is voltage times current, or pressure times volume of water. You could squirt a stream of water many feet (raising the voltage), but it's not a very large quantity of water (amps). Conversely, with your thumb off the end of the hose, the pressure (volts) isn't very high (it just flows out at whatever your tap pressure is), but the volume of water is significant (amps). Curious whether that is any clearer of an analogy?

globular-toast 6y ago
The thumb is commonly used as an analogy for a resistor because it limits the current. But with the hosepipe it seems to increase the voltage, which a resistor does not do. What you describe (trading current for voltage) is more like a transformer.