I wonder if he knew that 3kW is the same as 3000 watts. I wonder if he knew that dividing 3000 by 220 would tell him the (steady-state) current draw. I wonder if he had the faintest idea what answer you would get, if you divided 3000/220.
A couple of years ago I went into a convenience store for a cup of coffee. The cash-register was down. A customer had come in to buy something (can't remember what, let's pretend it was something that cost $3.45).
The customer was proffering a $5 bill. The trouble was that neither the store manager, nor the only other employee, nor the customer, could figure out how much change he should get back.
I tried to help. First I tried the most intuitive way, the one I've seen young children and illiterate people use: the item costs $3.45, add 5 cents to make it $3.50, add fifty cents more to make it $4, and finally add $1 to make it total $5. So by adding $1.55 to $3.45 we arrived at the $5 the customer gave you; that means you owe him $1.55 change.
All I got was blank looks.
So I showed them how to subtract $3.45 from $5.00, the way we all learned in elementary school, and got the same answer: you owe the customer $1.55 in change.
All I got was more blank looks. If they'd ever known how to subtract, they'd completely forgotten how.
Finally I said, guys, I taught math at college level for many years. Trust me, you owe the customer $1.55.
I still got blank looks. I guess they weren't about to trust me.
Probably not a bad idea, actually. Better not to blindly trust a stranger when it comes to money. 🙂
I had no more ideas, so I wished them well, and left. As I walked out of the store, all three people were still huddled together, forlornly standing around the dead cash register. I guess they were hoping it would magically come back to life and work out the change for them.
In a recent college physics lab at my workplace, students were working with a Bluetooth acceleration sensor mounted on a rotating turntable. They had to measure the radial distance from turntable centre to acceleration sensor, and write that down in their lab reports. They also had to use that measured value, along with the turntable's rotation rate, to verify that their measured data was consistent with the equation for circular acceleration.
The actual sensor-to-centre distance was 74 millimetres, to the nearest millimetre.
One team of three students wrote down the value they'd measured: 0.0007 metres.
Another team of three students measured and wrote down 750 metres.
Not one of those six young adults seemed to realize that the sensor was a hand-width away from the turntable centre; that 0.0007 metres is roughly the thickness of a human fingernail; or that 750 metres is far too big a distance to fit into a college lab, and that it would take you maybe ten to twelve minutes to walk that far.
I've seen similarly confounding oddities countless times during the 20+ years I've worked with junior-college students - young adults typically 18 - 21 years old. A lot of people have no sense at all of the magnitudes of everyday things. They don't know if a typical apple weighs 0.001 grams, 100 grams, or 10 tonnes.
I don't know what to make of it, but there it is. Part of our new reality.
-Gnobuddy
I did say that, asking him to calculate... he tried to show me the A/c had a lower capacity breaker, but it had 20A for a 1.5 ton (1800W max.) machine. That was when I asked him to leave first time.
He was saying 3000, I wrote as 3 kW here, because for the members it is easily understood.
Basically a monkey, with a neon tester/screw driver, a tape roll and insulated pliers. 4 mm tester bit was used to tighten MCB wires.😱
I am fond of tools, and particular about using the right one.
Anyway, I had a class mate in school, who flunked (repeated) 3rd and 8th grades, went to Louisiana, or some place in the South of the USA after 10th grade, and wrote to us he was a school topper there.
We said idiot is boasting again, or the Americans are really stupid.
But some friends in the USA, who stayed there after post graduate studies, do complain their kids are under peer pressure for social activities related to entertainment. Party takes precedence to study.
So, grin and bear it, and bring up the kids in a proper way, provided the wife allows it!
He was saying 3000, I wrote as 3 kW here, because for the members it is easily understood.
Basically a monkey, with a neon tester/screw driver, a tape roll and insulated pliers. 4 mm tester bit was used to tighten MCB wires.😱
I am fond of tools, and particular about using the right one.
Anyway, I had a class mate in school, who flunked (repeated) 3rd and 8th grades, went to Louisiana, or some place in the South of the USA after 10th grade, and wrote to us he was a school topper there.
We said idiot is boasting again, or the Americans are really stupid.
But some friends in the USA, who stayed there after post graduate studies, do complain their kids are under peer pressure for social activities related to entertainment. Party takes precedence to study.
So, grin and bear it, and bring up the kids in a proper way, provided the wife allows it!
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3000/200 = 15, accurate enough. Standard ratings series here has 16 and 20, and 16 will trip in brown out, possibly damage contacts. So 20. Took me 2 seconds.
Part of this is because schools do not allow calculators at all, till even 12th grade.
So you do it the hard way, and use your experience and judgement.
Part of this is because schools do not allow calculators at all, till even 12th grade.
So you do it the hard way, and use your experience and judgement.
Do you have illicit marijuana? The young adults I once knew were real damm good at judging 1 ounce by eye and hand.
🙂
The past tense seems to be key.
Several decades ago, in a small town, I've more than once encountered a small child - maybe as young as 7 or 8 years old - temporarily running the front of her parent's little shop, while mom and pop were doing something important in the back room.
The child was perfectly competent at taking your money, handing you your purchase, and figuring out the correct change in her head. Maybe she would go fetch mom or pop if you handed her a $20 bill rather than a $5 bill, just because she didn't want to take the risk of making a mistake with a larger sum of money. But with small dollar amounts, she had no worries doing the math on her own.
I'm betting lots of us have encountered something similar in the past, usually in a mom-n-pop store owned by immigrants from China, Vietnam, India, the Phillipines, or some other country where it's traditional to have your little kid help out, and where there isn't (wasn't?) as much fear of math.
-Gnobuddy