How much water did the kettle boil?

Question

Electronics

I apologize in advance for the stupidity of the question, today the calculator fell out of love with me (well, or the brain) ..)))

I poured exactly 2 liters of water into the kettle with measuring dishes and turned it on - simultaneously starting the stopwatch. The water boiled and the kettle turned off after 4 minutes and 22 seconds after being turned on. The meter added 0.1 kWh. The cost of electricity is 4.50 kopecks.
The question is, how much did the kettle "burn" for these 4 minutes in order to boil ONE liter ??? ))

Indications on the device

P(w) 1840.5 (мощность чайника)
I(a) 8.2 (ампераж)
U(v) 223.4 (напряжение в сети)
kWh 0.1 (счетчик)

Answer 1

There are 2 ways to determine:
1 way by the meter:
You have a tariff of 4.5 rubles per 1 kilowatt per hour. According to the meter, you spent 0.1 kilowatt per hour to boil water. Accordingly, 45 kopecks were spent to boil the kettle.
Method 2 according to the formula:
4 minutes 22 seconds \u003d 0.072 hours
1.842 kW * 0.072 h \u003d 0.132 kW * h
0.132 * 4.5 \u003d 0.59 kopecks

Answer 2

In 4.22 seconds, approximately
((223.4 * 8.2) / (60 * 60) * (4 * 60 + 22)) = 133 W was spent - which approximately corresponds to the meter reading 0.1 kWh
1 kW / h costs 4.50 kopecks. , 0.134 kWh will cost approximately 0.60 kopecks

Answer 3

The meter added 0.1 kWh.

Was it just the heater working? It looks like the truth, but the meter has too high a division value for such a calculation.
The device worked + -0.0725 hours
P (we take in kW) * 0.0725 * 4.5 \u003d 0.6003 rubles per 2 liters.
Per liter ~0.3 rubles

Answer 4

1.84 * 4.3 / 60 / 2 * 4.5 = 0.3 kopecks

Answer 5

I was about 18 years ago, in the 7th grade, so I was looking for the efficiency of the kettle. It turned out exactly 50% .
By the way, the formula can be derived directly from the dimensions

Дж = Вт * с = В * A * с
руб = руб/[кВт*ч] * кВт * ч

those.

Работа = Мощность * Время = Напряжение * Ток * Время
Деньги = Работа * Тариф

Just do not forget that for the convenience of the layman, the tariff is in kWh , and not in J , i.e.
1000*Вт*3600*с = 3600000Дж = 3,6*МДж

Answer 6

When pouring 1 liter into the kettle and 2 liters at a time and boiling, boiling ONE liter takes different energy and, accordingly, different money.
Boil 1 liter of water 100 times without resetting the meter. Divide the spent energy by 100 and multiply by the tariff. Let the community know the result.
Then 50 times, without resetting the meter, boil 2 liters of water each. Divide the spent energy by 100 and multiply by the tariff. And let us know too.

Answer 7

by an amount strictly less than 4.50 * 0.1 / 2
when heating the second liter, you need to spend energy equal to the energy spent on heating the first
PLUS
energy to maintain the temperature of the heated first
X < X + K
for accuracy, you can start with some formulas
but evil housing and communal services always will only be interested in meter readings (and payment on them)

Answer 8

The accuracy of the counter is too low, it is not known how much it actually turned out, 0.05 or 0.14.
For greater accuracy, it is worth at least 10 times in a row without dropping to boil, each time pouring cold water.
After each boiling, rinse the kettle with running cold water so that the kettle cools down, because. the body of the kettle retains heat from the last boil.