Hello friends,
Can someone explain to me what is the difference between volts, watts, ampere, and ampere-hour in very simple terms for someone that has not studied electronics using an analogy of drinking water with a straw from a bucket full of water?
Voltage would be the straw diameter and ampere the size of the bucket?
Using the water analogy …
Volts is the driving force , like water pressure .( the pressure you feel when putting your hand over a tap)
Amps is the current that “ flows” in wire , like water flowing ins pipe
You have it the wrong way around - the flow through the straw depends on the pressure on it ( volts) and that flow is the current (amps) .
A narrower straw has a higher resistance and restricts the flow ( current )
.
The bucket is really the battery … but analogies can only go so far. The size of bucket I guess s it’s capacity ( Ah) and the force required to stop the water water flowing out is the voltage
Watts is power . Volts x amps .
Amperehour is just amps x time .
So a 5Ah battery , simplistically , could supply 5amps for an hour or 1amp for 5 hours .
Really though , it’s worth looking into what voltage and current , power , ohms law really mean - analogies can only help so far ..
a drop of water falling a foot is an analog for a volt. a drop of water falling 5 feet would be an analog for 5 volts. it's about energy DIFFERENCE, not energy quantity
a steady flow of water through a straw would be an analog for an amp. a steady flow of water through a garden hose would be an analog for 20 amps.
volts times amps = watts
ampere hours is how much flow can be delivered for how long
in my solar generator, I have 3 solar panels that can deliver 20 volts under load at 10 amps each. wired in series, the 3: 20 volts add up to 60 volts, X 10 amps, = 600 watts
the MPPT controller converts that 600 watts to 24 volts at no more than 30 amps, , but it really never exceeds 25 amps because the panels just don't make that much power
the 24 volts charges up a 24V 100 AH battery. 600 watts max X 4 hours of peak solar panel energy per day = 2400 watt hours intake per day. 2400 watts divided by 24V =100 amps. My panel array is an exact fit for my battery, I can bring it from depleted to full in one day. more panels would require more battery, more battery would require more panels
ampere hours is the size of the bucket. amperes determines how fast you can fill the bucket, and volts does not translate to any real quality of water, but it's kind of 24V bourbon vs 12V beer. more volts, more jolt
You can arrange 2: 12V 100AH batteries in parallel, as 1: 12V 200 AH battery, or in series as 1: 24V 100 AH battery
That’s very clear now, thank you so much! 
Analogies are great. If you ever wish to springboard into the math and science behind the analogies, may I recommend the below site:
Electricity carries energy that you can measure in several different ways. Power, the rate at which equipment uses energy, is expressed as units called watts. The total amount of energy used over time is watt-hours. Amperes, or amps, measure current, the flow of electric charge. Volts measure its force. Amp-hours measure a battery’s electrical storage capacity, assuming its voltage stays constant.
Or watt-seconds which are called Joules - the SI unit.
A Watt-hour is 3.6 kJ.
In the water analogy... A broken/cut pipe is no resistance and nothing bad happens, except water floods all over the place. 
But if you cut a wire you get infinite resistance and no current flows.
And with electricity, zero resistance is a "short circuit". You get excess current and "bad things" happen (or maybe you blow a fuse of circuit breaker).
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